MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Applied and Environmental Microbiology' source. Thu, 09 Feb 2012 21:34:54 +0100 http://www.medworm.com/index.php?rid=5657705&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286979%26dopt%3DAbstract Authors: Davis MF, Baron P, Price LB, Williams D, Jeyaseelan S, Hambleton I, Diette GB, Breysse PN, McCormack MC Abstract Staphylococcus aureus in home environments may serve as a reservoir for human colonization, making sampling of indoor surfaces relevant to exposure assessment. Using laboratory experiments and application to homes of asthmatic children in Barbados, we characterize microbiological methods adapted for settings with transportation delays between sampling and initiation of culture. PMID: 22286979 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657705 Fri, 27 Jan 2012 05:00:00 +0100 5657705 http://www.medworm.com/index.php?rid=5657704&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286980%26dopt%3DAbstract Authors: Kobayashi T, Uchimura K, Deguchi S, Horikoshi K Abstract An inulinase-producing Microbulbifer sp. JAM-3301 was isolated from a deep-sea sediment. An inulin operon that contained three open reading frames was cloned and sequenced. Two of the three genes were expressed. One was an endo-inulinase, and the other was a β-fructofuranosidase. Both enzymes worked together to effectively degrade inulin. PMID: 22286980 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657704 Fri, 27 Jan 2012 05:00:00 +0100 5657704 http://www.medworm.com/index.php?rid=5657703&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286981%26dopt%3DAbstract Authors: Lüddeke F, Wülfing A, Timke M, Germer F, Weber J, Dikfidan A, Rahnfeld T, Linder D, Meyerdierks A, Harder J Abstract Castellaniella defragrans is a Betaproteobacterium capable of coupling the oxidation of monoterpenes to denitrification. Geraniol dehydrogenase (GeDH) activity was induced during growth with limonene in comparison to growth with acetate. The N-terminal sequence of the purified enzyme directed the cloning of the corresponding ORF, the first bacterial gene for a geraniol dehydrogenase (geoA, for geraniol oxidation pathway). The C. defragrans geraniol dehydrogenase (GeDH) is a homodimeric enzyme affiliating with the zinc-containing benzyl alcohol dehydrogenases in the medium-chain dehydrogenases/reductases (MDR) superfamily. The purified enzyme most efficient... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657703 Fri, 27 Jan 2012 05:00:00 +0100 5657703 http://www.medworm.com/index.php?rid=5657702&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286982%26dopt%3DAbstract Authors: Groff D, Benke PI, Batth TS, Bokinsky G, Petzold CJ, Adams PD, Keasling JD Abstract E. coli has the potential to be a powerful biocatalyst for the conversion of lignocellulosic biomass into useful materials such as biofuels and polymers. One important challenge in using E. coli for the transformation of biomass sugars is diauxie or sequential utilization of different types of sugars. We demonstrate that by increasing the intracellular levels of the transcription factor XylR, the preferential consumption of arabinose before xylose can be eliminated. In addition, XylR augmentation must be finely tuned for robust co-utilization of these two hemicellulosic sugars. Using a novel technique for scarless gene insertion, an additional copy of xylR was inserted into the araBAD opero... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657702 Fri, 27 Jan 2012 05:00:00 +0100 5657702 http://www.medworm.com/index.php?rid=5657701&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286983%26dopt%3DAbstract Authors: Totsika M, Wells TJ, Beloin C, Valle J, Allsopp LP, King NP, Ghigo JM, Schembri MA Abstract Trimeric autotransporter proteins (TAAs) are important virulence factors of many Gram-negative bacterial pathogens. A common feature of most TAAs is the ability to mediate adherence to eukaryotic cells or extracellular matrix (ECM) proteins via a cell-surface exposed passenger domain. Here we describe the characterization of EhaG, a TAA identified from enterohaemorrhagic E. coli (EHEC) O157:H7. EhaG is a positional orthologue of the recently characterized UpaG TAA from uropathogenic E. coli (UPEC). Similar to UpaG, EhaG localized at the bacterial cell surface and promoted cell aggregation, biofilm formation and adherence to a range of ECM proteins. However, the two orthologues displ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657701 Fri, 27 Jan 2012 05:00:00 +0100 5657701 http://www.medworm.com/index.php?rid=5657700&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286984%26dopt%3DAbstract Authors: Zhou W, Wang Y, Lin J Abstract Culture-independent sampling in conjunction with a functional cloning approach identified diverse antibiotic resistance genes for different classes of antibiotics in gut microbiomes from both conventionally raised and free range chickens. Many of the genes are phylogenetically distant from known resistance genes. Two unique genes that conferred ampicillin and spectinomycin resistance were also functional in Campylobacter, a distant relative of the E. coli host used to generate the genomic libraries. PMID: 22286984 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657700 Fri, 27 Jan 2012 05:00:00 +0100 5657700 http://www.medworm.com/index.php?rid=5657699&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286985%26dopt%3DAbstract Authors: Brown A, Smith K, Samuels TA, Lu J, Obare S, Scott ME Abstract Here we show that silver nanoparticles (AgNP) were intrinsically antibacterial while gold nanoparticles (AuNP) were antimicrobial only when ampicillin was bound to their surface. Both AuNP and AgNP functionalized with ampicillin were effective broad-spectrum bactericides against Gram-negative and Gram-positive bacteria. Most important, when AuNP and AgNP were functionalized with ampicillin they became potent bactericidal agents with unique properties that subverted antibiotic resistance mechanisms of multiple drug resistant bacteria. PMID: 22286985 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657699 Fri, 27 Jan 2012 05:00:00 +0100 5657699 http://www.medworm.com/index.php?rid=5657698&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286986%26dopt%3DAbstract Authors: Ruiz-Fons F, Fernández-de-Mera IG, Acevedo P, Gortázar C, de la Fuente J Abstract Environmental factors may drive tick ecology and therefore tick-borne pathogen (TBP) epidemiology, which determines the risk of animals and humans of getting infected by TBPs. For this reason, the aim of this study was to analyze the influence of environmental factors on the abundance of immature stages of Ixodes ricinus and on the prevalence of two zoonotic I. ricinus-borne pathogens in endemic natural foci. I. ricinus abundance was measured in nine sites in northern Iberian Peninsula by dragging the vegetation with a cotton flannelette and ungulate abundance was measured by means of dung counts. In addition to ungulate abundance, variables related to spatial location, climate and soil wer... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657698 Fri, 27 Jan 2012 05:00:00 +0100 5657698 http://www.medworm.com/index.php?rid=5657697&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286987%26dopt%3DAbstract Authors: Jakobsen TH, Bragason SK, Phipps RK, Christensen LD, van Gennip M, Alhede M, Skindersoe M, Larsen TO, Høiby N, Bjarnsholt T, Givskov M Abstract Foods with health promoting effects beyond nutritional values have been gaining increasing research focus in recent years, although not much has been published on this subject in relation to bacterial infections. With respect to treatment, a novel antimicrobial strategy, which is expected to transcend problems with selective pressures for antibiotic resistance, is to interrupt bacterial communication also known as quorum sensing (QS) by means of signal antagonists, so called QS inhibitors (QSIs). Furthermore, QSI agents offer a potential solution to the deficiencies associated with use of traditional antibiotics to treat infection... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657697 Fri, 27 Jan 2012 05:00:00 +0100 5657697 http://www.medworm.com/index.php?rid=5657696&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286988%26dopt%3DAbstract This study demonstrates that (A) mature input communities do not simply reassemble at mucosal sites during conventionalization - they first transform into a "pioneering" community and over time take on the appearance, in membership and structure, to the original input community and (B) the specific mucosal environment plays a role in shaping the community. PMID: 22286988 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657696 Fri, 27 Jan 2012 05:00:00 +0100 5657696 http://www.medworm.com/index.php?rid=5657695&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286989%26dopt%3DAbstract We report here that strain JS42 is chemotactic to 2NT, and the response is increased when cells are grown on compounds such as 2NT that are known to induce the first step of 2NT degradation. Assays with JS42 mutants unable to oxidize 2NT showed that the first step of 2NT metabolism was required for the induced response, but not for a portion of the constitutive response, indicating that 2NT itself is an attractant. The 2NT metabolite nitrite was shown to be a strong attractant for strain JS42, and sufficient nitrite was produced during the taxis assay to account for a large part of the induced response. A mutant with an inactivated ntdY gene, which is located adjacent to the 2NT degradation genes and codes for a putative methyl-accepting chemotaxis protein, showed a defect in taxis towards... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657695 Fri, 27 Jan 2012 05:00:00 +0100 5657695 http://www.medworm.com/index.php?rid=5657694&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286990%26dopt%3DAbstract Authors: Hall Sedlak R, Hnilova M, Grosh C, Fong H, Baneyx F, Schwartz D, Sarikaya M, Tamerler C, Traxler B Abstract Silver toxicity is a problem that microorganisms face in medical and environmental settings. Through exposure to silver compounds, some bacteria have adapted to growth in high concentrations of silver ions. Such adapted microbes may be dangerous as pathogens, but alternatively could be potentially useful in nanomaterial manufacturing applications. While naturally adapted isolates typically utilize efflux pumps to achieve metal resistance, we have engineered a silver tolerant E. coli strain utilizing a simple silver-binding peptide motif. A silver-binding peptide, AgBP2, was identified from a combinatorial display library and fused to the C-terminus of the E. coli mal... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657694 Fri, 27 Jan 2012 05:00:00 +0100 5657694 http://www.medworm.com/index.php?rid=5657693&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286991%26dopt%3DAbstract Authors: Han R, Qin L, Brown ST, Christensen JN, Beller HR Abstract We studied Cr isotopic fractionation during Cr(VI) reduction by Pseudomonas stutzeri strain RCH2. Despite the fact that strain RCH2 reduces Cr(VI) co-metabolically under both aerobic and denitrifying conditions and at similar specific rates, fractionation was markedly different under these two conditions (ε ∼2‰ aerobically and ∼0.4‰ under denitrifying conditions). PMID: 22286991 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657693 Fri, 27 Jan 2012 05:00:00 +0100 5657693 http://www.medworm.com/index.php?rid=5657692&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286992%26dopt%3DAbstract Authors: Deangelis KM, Firestone MK Abstract We evaluated phylogenetic clustering of bacterial and archaeal communities from redox-dynamic subtropical forest soils, defined by 16S rRNA and rRNA gene sequences. We observed significant clustering for the RNA-based but not the DNA-based communities, as well as increasing clustering over time of the highly-active taxa detected by rRNA only. PMID: 22286992 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657692 Fri, 27 Jan 2012 05:00:00 +0100 5657692 http://www.medworm.com/index.php?rid=5657691&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286993%26dopt%3DAbstract Authors: Seras-Franzoso J, Affentranger R, Ferrer-Navarro M, Daura X, Villaverde A, García-Fruitós E Abstract Escherichia coli β-galactosidase is probably the most widely used reporter enzyme in molecular biology, cell biology and biotechnology because of the easy detection of its activity. Its large size and tetrameric structure made this bacterial protein an interesting model for crystallographic studies and atomic mapping. In the present study, we investigate a version of Escherichia coli β-galactosidase produced under oxidizing conditions, in the cytoplasm of an Origami strain. Our data prove the activation of this microbial enzyme under oxidizing conditions and clearly show the occurrence of a disulfide bond in the β-galactosidase structure. Additionally, the formation of... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657691 Fri, 27 Jan 2012 05:00:00 +0100 5657691 http://www.medworm.com/index.php?rid=5657690&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286994%26dopt%3DAbstract Authors: Marsh EK, May RC Abstract The nematode Caenorhabditis elegans has been a powerful experimental organism for almost half a century. Over the past ten years, researchers have begun to exploit the power of C. elegans to investigate the biology of a number of human pathogens. This work has uncovered mechanisms of host immunity and pathogen virulence that are analogous to those involved during pathogenesis in humans or other animal hosts, as well as novel immunity mechanisms which appear unique to the worm. More recently, these investigations have uncovered details of the natural pathogens of C. elegans, including the description of a novel intracellular microsporidian parasite as well as new nodaviruses; the first identification of a viral infection of this nematode. In this r... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657690 Fri, 27 Jan 2012 05:00:00 +0100 5657690 http://www.medworm.com/index.php?rid=5657689&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286995%26dopt%3DAbstract Authors: Cellier G, Remenant B, Chiroleu F, Lefeuvre P, Prior P Abstract The ancient soil borne plant vascular pathogen Ralstonia solanacearum has evolved and adapted to cause severe damage on an unusually wide range of plants. In order to better describe and understand these adaptations, strains with very similar lifestyles and host specializations are grouped into ecotypes. We used comparative genomic hybridization to investigate three particular ecotypes in the American phylotype II group: 1) Brown rot strains from phylotypes IIB-1 and IIB-2, historically known as race 3 biovar 2 and clonal; 2) new pathogenic variants from phylotype IIB-4NPB that lack pathogenicity to banana but can infect many other plant species; and 3) Moko disease-causing strains from phylotypes IIB-3, IIB-4... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657689 Fri, 27 Jan 2012 05:00:00 +0100 5657689 http://www.medworm.com/index.php?rid=5657688&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286996%26dopt%3DAbstract Authors: Schmelcher M, Powell AM, Becker SC, Camp MJ, Donovan DM Abstract Staphylococci cause bovine mastitis with Staphylococcus aureus being responsible for the majority of the mastitis-based losses to the dairy industry (up to $2 billion/annum). Treatment is primarily with antibiotics that are often ineffective and potentially contribute to resistance development. Bacteriophage endolysins (peptidoglycan hydrolases) present a promising source of alternative antimicrobials. Here we evaluate two fusion proteins consisting of the streptococcal λSA2 endolysin endopeptidase domain fused to staphylococcal cell wall binding domains from either lysostaphin (λSA2-E-Lyso-SH3b) or the staphylococcal phage K endolysin, LysK (λSA2-E-LysK-SH3b). We demonstrate killing of 16 different S. aur... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657688 Fri, 27 Jan 2012 05:00:00 +0100 5657688 http://www.medworm.com/index.php?rid=5657687&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286997%26dopt%3DAbstract Authors: Schuster A, Tisch D, Seidl-Seiboth V, Kubicek CP, Schmoll M Abstract The cAMP-pathway represents a central signaling cascade with crucial functions in all organisms. Previous studies in Trichoderma reesei (anamorph of Hyprocrea jecorina) suggested a function of the cAMP signaling in regulation of cellulase gene expression. We were therefore interested, how the crucial components of this pathway, adenylate cyclase (ACY1) and cAMP dependent protein kinase A (PKA) would impact cellulase gene expression.We found that both ACY1 and PKAC1 (catalytic subunit 1) are involved in regulation of vegetative growth, but not essential for sexual development. Interestingly, our results showed considerably increased transcript abundance of cellulase genes in darkness compared to light (lig... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657687 Fri, 27 Jan 2012 05:00:00 +0100 5657687 http://www.medworm.com/index.php?rid=5657683&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286998%26dopt%3DAbstract Authors: Nikrad MP, Cottrell MT, Kirchman DL Abstract Environment conditions in the western Arctic Ocean range from constant light and nutrient depletion in summer to complete darkness and sea ice cover in winter. This seasonal environmental variation is likely to have an effect on the use of dissolved organic matter (DOM) by heterotrophic bacteria in surface water. However, this effect is not well studied and we know little about the activity of specific bacterial clades in the surface oceans. The use of DOM by three bacterial subgroups in both winter and summer was examined by microautoradiography combined with fluorescence in situ hybridization. We found selective use of substrates by these groups, although the abundance of Ant4D3 (Antarctic Gammaproteobacteria), Polaribacter (B... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657683 Fri, 27 Jan 2012 05:00:00 +0100 5657683 http://www.medworm.com/index.php?rid=5657677&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22286999%26dopt%3DAbstract Authors: Yuan H, Ge T, Chen C, O'Donnell AG, Wu J Abstract Soils were incubated for 80 days in a continuously labeled (14)C-CO(2) atmosphere to measure the amount of labeled C incorporated into the microbial biomass. Microbial assimilation of (14)C differed between soils and accounted for 0.12% to 0.59% of soil organic carbon (SOC). Assuming a terrestrial area of 1.4 × 10(8) km(2), this represents a potential global sequestration of 0.6 to 4.9 Pg C yr(-1). Estimated global C sequestration rates suggest a 'missing sink' for carbon of between 2-3 Pg C yr(-1). To determine whether (14)C-CO(2) incorporation was mediated by autotrophic microorganisms, the diversity and abundance of CO(2)-fixing bacteria and algae were investigated using clone library sequencing, terminal restriction fr... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657677 Fri, 27 Jan 2012 05:00:00 +0100 5657677 http://www.medworm.com/index.php?rid=5657676&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287000%26dopt%3DAbstract Authors: Stackhouse RR, Faith NG, Kaspar CW, Czuprynski CJ, Wong AC Abstract Salmonella enterica serovar Enteritidis strain E40 filaments were developed at a reduced water activity (a(w)) of 0.95 in tryptic soy broth (TSB) or tryptic soy agar (TSA) supplemented with 8% or 7% NaCl, respectively. Filament formation was accompanied by an increase of biomass without an increase in colony-forming units (CFU), and was affected by incubation temperature and the physical milieu. The greatest amount of filaments was recovered from TSA with 7% NaCl incubated at 30°C. Within 2 h of transfer to fresh TSB, filaments started to septate into normal-sized cells, resulting in a rapid increase in CFU. S. Enteritidis E40 filaments were not more tolerant of low and high temperature stresses than non-... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657676 Fri, 27 Jan 2012 05:00:00 +0100 5657676 http://www.medworm.com/index.php?rid=5657675&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287001%26dopt%3DAbstract Authors: Kixmüller D, Greie JC Abstract Gradually inducible expression vectors which are governed by variations of growth conditions are powerful tools for gene expression of conditionally lethal mutants. Furthermore, controlled expression allows monitoring of overproduction of proteins at various stages in their expressing hosts. For Halobacterium salinarum, which is often used as a paradigm for halophilic Archaea, such an inducible expression system is not available to date. Here we show that the kdp promoter (Pkdp), which facilitates gene expression upon K(+) limitation, can be used to establish such a system for molecular applications. Pkdp features a rather high expression rate with an approximately 50-fold increase that can be easily varied by K(+) concentrations in the grow... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657675 Fri, 27 Jan 2012 05:00:00 +0100 5657675 http://www.medworm.com/index.php?rid=5657674&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287002%26dopt%3DAbstract In this study, through extensive biochemical and genetic studies, we identified a pyruvate oxidase (pox) gene in S. oligofermentans. A pox deletion mutant completely lost Pox activity, while pox ectopically expressed restored activity. Pox was determined to produce most of the H(2)O(2) in the earlier growth phase and log phase, while Lox mainly contributed to H(2)O(2) production in stationary phase. Both pox and lox were expressed throughout the entire growth phase, while expression of lox gene increased for about 2.5 fold when cells entered stationary phase. Since lactate accumulation to a large degree occurred in stationary phase, the differential Pox- and Lox-generated H(2)O(2) can be attributed to differential gene expression and substrate availability. Interestingly, inactivation of p... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657674 Fri, 27 Jan 2012 05:00:00 +0100 5657674 http://www.medworm.com/index.php?rid=5657673&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287003%26dopt%3DAbstract In this study we demonstrate that the histone-like nucleoid structuring protein is a repressor of exopolysaccharide (vps) biosynthesis genes and biofilm formation. PMID: 22287003 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657673 Fri, 27 Jan 2012 05:00:00 +0100 5657673 http://www.medworm.com/index.php?rid=5657672&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287004%26dopt%3DAbstract In this study, we examined 568 isolates of F. graminearum collected from maize at eight locations in Korea. We used amplified fragment length polymorphisms (AFLPs) to identify four lineages (2, 3, 6 and 7); lineage 7 was the most common (75%), followed by lineage 6 (12%), lineage 3 (12%) and lineage 2 (1%). The genetic identity among populations was high ( > 0.98) and the effective migration rate between locations was higher than that between lineages. Female fertility varied by lineage: all lineage 7 isolates were fertile while 70%, 26%, and 14% of the isolates in lineages 6, 3 and 2, respectively, were fertile. All lineage 3 and lineage 7 isolates produced deoxynivalenol, whereas most lineage 2 and 6 isolates produced nivalenol. Genotypic diversity in lineage 3 and lineage 6 populatio... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657672 Fri, 27 Jan 2012 05:00:00 +0100 5657672 http://www.medworm.com/index.php?rid=5657671&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287005%26dopt%3DAbstract Authors: Somerton B, Palmer J, Brooks J, Smolinski E, Lindsay D, Flint S Abstract Free ions of Na(+), K(+), Ca(2+), and Mg(2+) influenced the optical density of planktonic cultures of thermophilic bacilli. Anoxybacillus flavithermus E16 and Geobacillus sp. F75 (milk powder manufacturing plant isolates), and A. flavithermus DSM 2641 and G. thermoleovorans DSM 5366, were studied. Ca(2+) and Mg(2+) were associated with increases in optical density more so than Na(+) and K(+). Overall, it appeared that Ca(2+) and/or Mg(2+) was required for the production of protein in thermophilic bacilli, as shown by results obtained with A. flavithermus E16, which was selected for further study. PMID: 22287005 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657671 Fri, 27 Jan 2012 05:00:00 +0100 5657671 http://www.medworm.com/index.php?rid=5657670&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287006%26dopt%3DAbstract Authors: Centanni M, Bergmann S, Turroni S, Hammerschmidt S, Chhatwal GS, Brigidi P, Candela M Abstract The capacity to intervene with the host plasminogen system has been recently considered an important component in the interaction process between B. animalis subsp. lactis and the human host. However, its significance in the bifidobacterial microecology within the human gastrointestinal tract is still an open question. Here we demonstrated that human plasminogen favors the B. animalis subsp. lactis BI07 adhesion to HT29 cells. Prompting the HT29 cell capacity to activate plasminogen, TNF-α modulated the plasminogen-mediated bacteria-enterocyte interaction, reducing the bacterial adhesion to the enterocytes and enhancing the migration to the luminal compartment. PMID: 2228700... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657670 Fri, 27 Jan 2012 05:00:00 +0100 5657670 http://www.medworm.com/index.php?rid=5657669&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287007%26dopt%3DAbstract Authors: Tuladhar E, de Koning M, Fundeanu I, Beumer R, Duizer E Abstract Virucidal activity of immobilized quaternary ammonium compounds (IQACs) coated onto glass and plastic surfaces was tested against enveloped influenza A (H1N1) virus and non-enveloped poliovirus Sabin1. The IQACs tested were virucidal against the influenza virus within 2 min but no virucidal effect against poliovirus was found in 6 h. PMID: 22287007 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657669 Fri, 27 Jan 2012 05:00:00 +0100 5657669 http://www.medworm.com/index.php?rid=5657668&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287008%26dopt%3DAbstract Authors: Gómez-Santos N, Treuner-Lange A, Moraleda-Muñoz A, García-Bravo E, García-Hernández R, Martínez-Cayuela M, Pérez J, Søgaard-Andersen L, Muñoz-Dorado J Abstract Myxococcus xanthus is widely used as a model system for studying gliding motility, multicellular development, and cellular differentiation. Moreover, M. xanthus is a rich resource of novel secondary metabolites. The analysis of these processes has been hampered by the limited set of tools for inducible gene expression. Here we report the construction of a set of plasmid vectors to allow copper-inducible gene expression in M. xanthus. Analysis of the effect of copper on the strain DK1622 revealed that copper concentrations up to 500 μM during growth and 60 μM during development do not affect physiological ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657668 Fri, 27 Jan 2012 05:00:00 +0100 5657668 http://www.medworm.com/index.php?rid=5657667&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287009%26dopt%3DAbstract This study also highlight the importance of conducting research with biological materials obtained from recognized microbial collections. PMID: 22287009 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657667 Fri, 27 Jan 2012 05:00:00 +0100 5657667 http://www.medworm.com/index.php?rid=5657666&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287010%26dopt%3DAbstract Authors: Jiang M, Stephanopoulos G, Pfeifer BA Abstract Escherichia coli offers unparalleled engineering capacity in the context of heterologous natural product biosynthesis. However, like other heterologous hosts, cellular metabolism must be designed or re-designed to support final compound formation. This task is at once complicated and aided by the fact that the cell does not natively produce an abundance of natural products. As such, the metabolic engineer will avoid complicated interactions with native pathways closely associated with the outcome of interest, but this convenience is tempered by the need to implement the required metabolism to allow functional biosynthesis. This review will focus on engineering E. coli for the purpose of polyisoprene formation as related to tho... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657666 Fri, 27 Jan 2012 05:00:00 +0100 5657666 http://www.medworm.com/index.php?rid=5657665&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287011%26dopt%3DAbstract Authors: Jiang Y, Xiao P, Yu G, Sano T, Pan Q, Li R Abstract New insights into the distribution and biochemistry of the cyanotoxin cylindrospermopsin (CYN) have been provided by the recent determination of its biosynthesis gene cluster (cyr) in several cyanobacterial species. Raphidiopsis curvata CHAB1150 isolated from China was analyzed for CYN analogues. Only 7-deoxy-CYN was detected in the cell extracts. The cyr gene clster of R. curvata CHAB1150 was sequenced, and the cyr genes of this strain were found to have extremely high similarities (96% to 100%) to those from other nostocalean species. These species include Cylindrospermopsis raciborskii AWT205, Aphanizomenon sp. 10E6, and Aphanizomenon ovalisporum ILC-146. Insertion mutation was identified within the cyrI gene, and tran... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657665 Fri, 27 Jan 2012 05:00:00 +0100 5657665 http://www.medworm.com/index.php?rid=5657664&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287012%26dopt%3DAbstract Authors: Fetzner S Abstract Ring-cleaving dioxygenases catalyze key reactions in the aerobic microbial degradation of aromatic compounds. Many pathways converge to catecholic intermediates, which are subject to ortho or meta cleavage by intradiol or extradiol dioxygenases, respectively. However, a number of degradation pathways proceed via non-catecholic hydroxy-substituted aromatic carboxylic acids like gentisate, salicylate, 1-hydroxy-2-naphthoate, or aminohydroxybenzoates. The ring-cleaving dioxygenases active towards these compounds belong to the cupin superfamily, which is characterized by a six-stranded β-barrel fold and conserved amino acid motifs that provide the 3His- or 2-3His-1Glu-ligand environment of a divalent metal ion. Most cupin-type ring-cleavage dioxygenases use... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657664 Fri, 27 Jan 2012 05:00:00 +0100 5657664 http://www.medworm.com/index.php?rid=5657663&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22287013%26dopt%3DAbstract Authors: Eichorst SA, Kuske CR Abstract Many bacteria and fungi are known to degrade cellulose in culture, but their combined response to cellulose in different soils is unknown. Replicate soil microcosms amended with (13)C-cellulose were used to identify bacterial and fungal communities responsive to cellulose in five geographically and edaphically different soils. Diversity and composition of the cellulose-responsive communities was assessed by DNA-stable isotope probing combined with Sanger sequencing of small subunit and large subunit rRNA genes for the bacterial and fungal community, respectively. In each soil, the (13)C enriched, cellulose-responsive communities were of distinct composition compared to the original soil community or (12)C-non-enriched communities. The composi... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5657663 Fri, 27 Jan 2012 05:00:00 +0100 5657663 http://www.medworm.com/index.php?rid=5638139&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267658%26dopt%3DAbstract In this study, the amicetin biosynthetic gene cluster was cloned from Streptomyces vinaceus-drappus NRRL 2363 and localized on a 37 kb contiguous DNA region. Heterologous expression of the amicetin biosynthetic gene cluster in Streptomyces livdians TK64 resulted in the production of amicetin and its analogues, thereby confirming the identity of the ami-gene cluster. In silico sequence analysis revealed that 21 genes were putatively involved in amicetin biosynthesis, including 3 for regulation and transportation, 10 for disaccharide biosynthesis, and 8 for the formation of amicetin skeleton by the linkage of cytosine, para-benzoic acid (PABA), and the terminal (+)-α-methylserine moieties. The inactivation of the benzoate-CoA ligase gene amiL and the N-acetyltransferase gene amiF, led to tw... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638139 Fri, 20 Jan 2012 05:00:00 +0100 5638139 http://www.medworm.com/index.php?rid=5638138&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267659%26dopt%3DAbstract Authors: Szabo JG, Muhammad N, Heckman L, Rice EW, Hall J Abstract Germination was evaluated as an enhancement to decontamination methods for removing Bacillus spores from drinking water infrastructure. Germinating spores before chlorinating cement-mortar or flushing corroded iron was more effective than chlorinating or flushing alone. PMID: 22267659 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638138 Fri, 20 Jan 2012 05:00:00 +0100 5638138 http://www.medworm.com/index.php?rid=5638137&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267660%26dopt%3DAbstract Authors: Ortiz-Marquez JC, Do Nascimento M, Dublan MD, Curatti L Abstract Concerns on depletion of the world's reserves of oil and global climate change have promoted during the last years an intensification of research and development towards the production of biofuels and other alternative sources of energy. There is currently much interest in developing the technology for third generation biofuels from microlgae biomass mainly because of its potential of high yield and reduced land use change in comparison with biofuels derived from plant feedstocks. Regardless the nature of the feedstock, the use of fertilizers, especially nitrogen, entails a potential economic and environmental drawback for the sustainability of biofuels production. In this work we have studied the possibility... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638137 Fri, 20 Jan 2012 05:00:00 +0100 5638137 http://www.medworm.com/index.php?rid=5638136&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267661%26dopt%3DAbstract Authors: Leisch H, Shi R, Grosse S, Morley K, Bergeron H, Cygler M, Iwaki H, Hasegawa Y, Lau PC Abstract A dimeric Baeyer-Villiger monooxygenase (BVMO) catalyzing the lactonization of 2-oxo-Δ(3)-4,5,5-trimethylcyclopentenylacetyl-CoA, a key intermediate in the metabolism of camphor by Pseudomonas putida ATCC 17453 had been initially characterized in 1983 by Trudgill and co-workers (H.J. Ougham, D.G. Taylor, and P.W. Trudgill, J. Bacteriol. 153:140-152, 1983). Here we have cloned and overexpressed the 2-oxo-Δ(3)-4,5,5-trimethylcyclopentenylacetyl-CoA monooxygenase (OTEMO) in Escherichia coli, and determined its three-dimensional structure with bound FAD at 1.95 Å resolution as well as with bound FAD and NADP(+) at 2.0 Å resolution. OTEMO represents the first homodimeric type 1 B... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638136 Fri, 20 Jan 2012 05:00:00 +0100 5638136 http://www.medworm.com/index.php?rid=5638135&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267662%26dopt%3DAbstract Authors: Xu M, Schnorr J, Keibler B, Simon HM Abstract We took advantage of a plant-root enrichment culture system to characterize mesophilic soil archaea selected through use of organic and inorganic amendments. Comparative analysis of 16S rRNA and amoA genes indicated that specific archaeal clades were selected under different conditions. Three amoA sequence clades were identified, while for a fourth group, identified by 16S rRNA gene analysis alone and referred to as the "root" clade, we detected no corresponding amoA gene. The amoA-containing archaea were present in media with either organic or inorganic amendments, while archaea representing the root clade were present only when organic amendment was used. Analysis of amoA gene abundance and expression, together with nitrifica... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638135 Fri, 20 Jan 2012 05:00:00 +0100 5638135 http://www.medworm.com/index.php?rid=5638134&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267663%26dopt%3DAbstract Authors: Ishijima SA, Hayama K, Burton JP, Reid G, Okada M, Matsushita Y, Abe S Abstract Oral candidiasis is often accompanied with severe inflammation resulting in a decline in the quality of life of immunosuppressed individuals and elderly people. To develop a new oral therapic options for candidiasis, a non-pathogenic commensal oral probiotic microorganism, Streptococcus salivarius K12 was evaluated for its ability to modulate Candida albicans growth in vitro and its therapeutic activity was tested on an experimental oral candidiasis model.In vitro inhibition of mycelial growth of C. albicans was determined by plate assay and fluorescent microscopy. Addition of S. salivarius K12 to modified RPMI1640 culture medium inhibited the adherence of C. albicans to the plastic petri dish ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638134 Fri, 20 Jan 2012 05:00:00 +0100 5638134 http://www.medworm.com/index.php?rid=5638133&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267664%26dopt%3DAbstract In this study, colour changes of C. lytica colonies were observed at various angles of direct illumination or observation. Its iridescent green appearance was dominant on various growth media. Red and violet colours were also discerned on colony edges. Remarkable C. lytica bacterial iridescence was revealed and characterized using high resolution optical spectrometry. In addition to this, by culturing other bacterial strains, to which various forms of faintly iridescent traits have previously been attributed, we identify four principle appearance characteristics of structural colour in prokaryotes. A new general classification of bacterial iridescence is therefore proposed in this study. Furthermore, a specific separate class is described for iridescent C. lytica strains because they exhib... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638133 Fri, 20 Jan 2012 05:00:00 +0100 5638133 http://www.medworm.com/index.php?rid=5638132&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267665%26dopt%3DAbstract Authors: Wang X, Miller EN, Yomano LP, Shanmugam KT, Ingram LO Abstract Expression arrays were used to identify 4 putative oxidoreductases that were up-regulated (>3-fold) by furfural (15 mM,15 min). Plasmid expression of one (ucpA) increased furan tolerance in ethanologenic strain LY180, and wild type strain W. Deleting ucpA decreased furfural tolerance. Although the mechanism remains unknown, the cryptic ucpA gene is now associated with a phenotype, furan resistance. PMID: 22267665 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638132 Fri, 20 Jan 2012 05:00:00 +0100 5638132 http://www.medworm.com/index.php?rid=5638131&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267666%26dopt%3DAbstract Authors: Wang X, Li X, Zhao C, Hu P, Chen H, Liu Z, Liu G, Wang Z Abstract The transition period is a severe challenge to dairy cows. Glucose supply cannot meet demand and body fat is mobilized, potentially leading to negative energy balance (NEB), ketosis or fatty liver. Propionate produces glucose by gluconeogenesis, which generation depends heavily on the number and species of microbes. In present study we analyzed the rumen microbiome composition of cows in the transition period, cows with ketosis and non-perinatal cows using terminal restriction fragment length polymorphism (TRFLP) analysis of 16S rRNA genes and Quantitative PCR. TRFLP analysis indicated that the quantity of Veillonellaceae was reduced, and that of Streptococcaceae was increased in rumen samples from the trans... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638131 Fri, 20 Jan 2012 05:00:00 +0100 5638131 http://www.medworm.com/index.php?rid=5638130&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267667%26dopt%3DAbstract Authors: Rodríguez-Rubio L, Martínez B, Rodríguez A, Donovan DM, García P Abstract Virion-associated peptidoglycan hydrolases have a potential as antimicrobial agents due to their ability to lyse Gram positive bacteria on contact. In this work, our aim was to improve the lytic activity of HydH5, a virion associated peptidoglycan hydrolase from the Staphylococcus aureus bacteriophage vB_SauS-phi-IPLA88. Full-length HydH5 and two truncated derivatives containing only the CHAP domain exhibited high lytic activity against live S. aureus cells. In addition, three different fusion proteins were created between lysostaphin and HydH5, each of which showed higher staphylolytic activity than the parental enzyme or its deletion construct. Both parental and fusion proteins lysed S. aureus ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638130 Fri, 20 Jan 2012 05:00:00 +0100 5638130 http://www.medworm.com/index.php?rid=5638129&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267668%26dopt%3DAbstract Authors: Mosher JJ, Phelps TJ, Podar M, Hurt RA, Campbell JH, Drake MM, Moberly JG, Schadt CW, Brown SD, Hazen TC, Arkin AP, Palumbo AV, Faybishenko BA, Elias DA Abstract Determining the success of in-situ bioremediation strategies is complex. By using controlled laboratory conditions, the influence of individual variables such as U(VI), Cr(VI) and electron donor and acceptors on community structure, dynamics, and the metal-reducing potential can be studied. Triplicate anaerobic, continuous-flow reactors were inoculated with Cr(VI) contaminated groundwater from the Hanford, Washington 100-H area, amended with lactate and incubated for 95 days to obtain stable, enriched communities. The reactors were kept anaerobic with N(2) gas (9ml/min) flushing the headspace and were fed a define... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638129 Fri, 20 Jan 2012 05:00:00 +0100 5638129 http://www.medworm.com/index.php?rid=5638128&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267669%26dopt%3DAbstract Authors: Tariq M, Bruijs C, Kok J, Krom BP Abstract Enterococcus faecalis, a commensal of the gastrointestinal tract and an opportunistic pathogen, has the ability to adhere to surfaces and form biofilms. It has been shown earlier that only 10 to 20 percent of a E. faecalis OG1RF culture expresses endocarditis and biofilm-associated pili (Ebp) which are involved in biofilm formation. Another study revealed that E. faecalis clinical isolates, as well as OG1RF, are heterogeneous with respect to their apparent zeta potential which was also correlated with increased ability to form biofilm. The aim of this study was to demonstrate that the heterogeneity in the presence of Ebp is correlated to that in apparent zeta potential. Heterogeneous cultures of OG1RF showed two distinct subpopula... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638128 Fri, 20 Jan 2012 05:00:00 +0100 5638128 http://www.medworm.com/index.php?rid=5638127&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267670%26dopt%3DAbstract Authors: Mo S, Yoo YJ, Ban YH, Lee SK, Kim E, Suh JW, Yoon YJ Abstract FK506 is an important 23-membered polyketide macrolide with immunosuppressant activity. Its entire biosynthetic gene cluster was previously cloned from Streptomyces sp. KCTC 11604BP, and sequence analysis identified three putative regulatory genes, tcs2, tcs7 and fkbN, which encode proteins with a high similarity to the AsnC family transcriptional regulators, LysR-type transcriptional regulators, and LAL family transcriptional regulators, respectively. Overexpression and in-frame deletion of tcs2 did not affect the production of FK506 or co-occurring FK520 compared to the wild-type strain, suggesting that tcs2 is not involved in their biosynthesis. fkbN overexpression improved the levels of FK506 and FK520 produ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638127 Fri, 20 Jan 2012 05:00:00 +0100 5638127 http://www.medworm.com/index.php?rid=5638126&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267671%26dopt%3DAbstract Authors: Rhodes ME, Oren A, House CH Abstract 16S rRNA amplicon libraries from a haloarchaeal bloom in the hypersaline Dead Sea in 1992 were analyzed together with the 2007 residual population along with simulated blooms in experimental mesocosms. Significant population shifts were observed during the bloom and surprisingly a signature from the bloom was retained 15 years later. PMID: 22267671 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638126 Fri, 20 Jan 2012 05:00:00 +0100 5638126 http://www.medworm.com/index.php?rid=5638125&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267672%26dopt%3DAbstract This study provides novel insight into the nicotine-degrading mechanism at the genetic level in Pseudomonas spp. PMID: 22267672 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638125 Fri, 20 Jan 2012 05:00:00 +0100 5638125 http://www.medworm.com/index.php?rid=5638124&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267673%26dopt%3DAbstract Authors: Mullany P, Williams R, Langridge GC, Turner DJ, Whalan R, Clayton C, Lawley T, Hussain H, McCurrie K, Morden N, Allan E, Roberts AP Abstract The insertion sites of the conjugative transposon Tn916 in the anaerobic pathogen Clostridium difficile were determined using Illumina Solexa high-throughput DNA sequencing of Tn916 insertion libraries in two different clinical isolates: 630ΔE, an erythromycin-sensitive derivative of 630 (ribotype 012) and the ribotype 027 isolate R20291 which was responsible for a severe outbreak of C. difficile disease. A consensus fifteen base pair Tn916 insertion sequence was identified which was similar in both strains although an extended consensus sequence was observed in R20291. A search of the C. difficile 630 genome showed that the Tn916 in... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638124 Fri, 20 Jan 2012 05:00:00 +0100 5638124 http://www.medworm.com/index.php?rid=5638123&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267674%26dopt%3DAbstract USE OF AMPLIFIED-FRAGMENT LENGTH POLYMORPHISM TO STUDY THE ECOLOGY OF CAMPYLOBACTER JEJUNI IN ENVIRONMENTAL WATER AND TO PREDICT MULTI-LOCUS SEQUENCE TYPING CLONAL COMPLEXES. Appl Environ Microbiol. 2012 Jan 20; Authors: Lévesque S, St-Pierre K, Frost E, Arbeit RD, Michaud S Abstract We determined the genetic variability among water isolates of Campylobacter jejuni using AFLP and MLST. Across a highly diverse collection of isolates, AFLP clusters did not correlate with MLST clonal complexes, suggesting that ALFP is not reliable for deciphering population genetic relationships and may be problematic for larger epidemiologic analyses. PMID: 22267674 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638123 Fri, 20 Jan 2012 05:00:00 +0100 5638123 http://www.medworm.com/index.php?rid=5638116&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267675%26dopt%3DAbstract Authors: Zou L, Zengb Q, Lin H, Gyaneshwar P, Chen G, Yang CH Abstract The hrp (hypersensitive response and pathogenicity) genes of Dickeya dadantii 3937 encode a type III secretion system (T3SS) which is essential for its full virulence. Previous studies of the T3SS regulation in D. dadantii 3937 revealed that the expression of the hrp genes is regulated by a master regulator HrpL through the HrpX-HrpY-HrpS-HrpL and GacS-GacA-rsmB-RsmA pathways. In this work, we identified a novel regulator of the SlyA/MarR family, SlyA, which regulates hrp genes of the HrpL regulon in parallel with HrpL in Dickeya dadantii. SlyA regulates the T3SS in a two-tier manner. It negatively regulates the expression of hrpL by down-regulating hrpS and up-regulating rsmA. Interestingly, concomitant with it... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638116 Fri, 20 Jan 2012 05:00:00 +0100 5638116 http://www.medworm.com/index.php?rid=5638107&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267676%26dopt%3DAbstract Authors: Foulongne-Oriol M, Rodier A, Rousseau T, Savoie JM Abstract As in other crops, yield is an important trait to be selected in edible mushrooms, but its inheritance is poorly understood. Therefore, we have investigated the complex genetic architecture of yield-related traits in Agaricus bisporus through the mapping of quantitative trait loci (QTL), using a second generation hybrids progeny derived from a cross between a wild strain and a commercial cultivar. Yield, average weight per mushroom, number of fruiting bodies per m(2), earliness and cap colour were evaluated in two independent experiments. A total of 23 QTL were detected for 7 yield-related traits. These QTL explained together between 21% (two-flushes-yield) and 59% (earliness) of the phenotypic variation. Fifteen ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638107 Fri, 20 Jan 2012 05:00:00 +0100 5638107 http://www.medworm.com/index.php?rid=5638086&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22267677%26dopt%3DAbstract Authors: Buasri W, Panbangred W Abstract Seven distinct Bacillus thuringiensis subsp. aizawai (BTA) integrants, were constructed by carrying the chitinase (chiBlA) gene from B. licheniformis under control of the cry11Aa promoter and terminator with and without p19 and p20 genes. The toxicity of BTA integrants against 2(nd) instar Spodoptera litura larvae was increased 1.8-4.6 fold when compared to that of the wild type strain (BTA1). Surprisingly, the enhanced toxicity in some strains of BTA integrants (BtaP19CS, BtaP19CSter and BtaCAT) correlated with an increase in toxin formation. To investigate the role of these genes in toxin production the expression profiles of the toxin genes, cry1Aa and chiBlA as well as their transcriptional regulators (sigK and sigE) were analyzed by qua... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5638086 Fri, 20 Jan 2012 05:00:00 +0100 5638086 http://www.medworm.com/index.php?rid=5597699&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247126%26dopt%3DAbstract Authors: de Sarrau B, Clavel T, Clerté C, Carlin F, Giniès C, Nguyen-The C Abstract The impact of simultaneous anaerobiosis and low temperature on growth parameters, metabolism, and membrane properties of Bacillus cereus ATCC 14579 was studied. No growth was observed under anaerobiosis at 12°C. In bioreactors, growth rates and biomass production were drastically reduced by simultaneous anaerobiosis and low temperature (15°C). The two conditions had a synergistic effect on biomass reduction. In anaerobic cultures, fermentative metabolism was modified by low temperature, with a marked reduction in ethanol production leading to a lower ability of NAD(+) production. Anaerobiosis reduced unsaturated fatty acids at both low optimal temperatures. In addition, simultaneous anaerobiosis... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597699 Fri, 13 Jan 2012 05:00:00 +0100 5597699 http://www.medworm.com/index.php?rid=5597698&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247127%26dopt%3DAbstract This study focused on identification and functional analysis of the PGAPs in a haloarchaeon Haloferax mediterranei. These PGAPs were visualized with two-dimensional gel electrophoresis (2-DE) and identified by MALDI TOF/TOF MS. The most abundant protein on the granules was identified as a hypothetical protein, designated as PhaP. A genome-wide analysis revealed the phaP gene is located upstream of the previously identified phaEC genes. Through an integrative approach of gene knockout/complementation and fermentation analyses, we demonstrated that this PhaP is involved in PHA accumulation. The ΔphaP mutant was defective in both PHA biosynthesis and cell growth compared to the wild-type strain. Additionally, transmission electron microscopy results indicated that the number of the PHA granu... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597698 Fri, 13 Jan 2012 05:00:00 +0100 5597698 http://www.medworm.com/index.php?rid=5597697&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247128%26dopt%3DAbstract Authors: Wietz M, Månsson M, Bowman JS, Blom N, Ng Y, Gram L Abstract We isolated sixteen antibiotic-producing bacterial strains throughout the central Arctic Ocean, including seven Arthrobacter spp. with almost identical 16S rRNA gene sequences. These strains were numerically rare as revealed from 454 pyrosequencing libraries. Arthrobacter spp. produced arthrobacilins A-C under different culture conditions, but other, not identified compounds likely contributed to their antibiotic activity. PMID: 22247128 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597697 Fri, 13 Jan 2012 05:00:00 +0100 5597697 http://www.medworm.com/index.php?rid=5597696&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247129%26dopt%3DAbstract The objective of this study was to identify prominent phylogenetic groups of dairy-associated aerobic sporeformers and characterize representative isolates for phenotypes relevant to growth in milk. Analysis of sequence data for a 632 nt fragment of rpoB showed that 1,288 dairy associated isolates (obtained from raw and pasteurized milk, and dairy farm environments), grouped into two major divisions representing (i) the genus Paenibacillus (737 isolates including the species P. odorifer, P. graminis, and P. amylolyticus s.l.) and (ii) a division that includes Bacillus (n = 467; e.g., B. licheniformis s.l., B. pumilus, B. weihenstephanensis) and genera formerly classified as Bacillus (n = 84; e.g., Viridibacillus spp.). When isolates representing the most common rpoB allelic types (AT) were... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597696 Fri, 13 Jan 2012 05:00:00 +0100 5597696 http://www.medworm.com/index.php?rid=5597695&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247130%26dopt%3DAbstract Authors: Bian J, Fenno JC, Li C Abstract Herein, we report that a modified gentamicin cassette and a PCR-based method can be used for targeted mutagenesis of the oral spirochete Treponema denticola. This approach minimizes polar effect and spontaneous antibiotic resistance. Therefore, it can serve as a reliable tool for genetic manipulation of T. denticola. PMID: 22247130 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597695 Fri, 13 Jan 2012 05:00:00 +0100 5597695 http://www.medworm.com/index.php?rid=5597694&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247131%26dopt%3DAbstract Authors: Santos F, Yarza P, Parro V, Meseguer I, Rosselló-Móra R, Antón J Abstract Hypersaline close-to-saturation environments harbor an extremely high concentration of virus-like particles but the number of halovirus isolated so far is still very low. Haloviruses can be directly studied from natural samples using different culture-independent techniques that include transmission electron microscopy, pulsed field gel electrophoresis and different metagenomic approaches. Here, we review the findings of these studies, with a main focus on the metagenomic approaches. The analysis of bulk viral nucleic acids directly retrieved from the environment allows estimations of viral diversity, activity, dynamics and tentative host assignment. Results point to a diverse and active viral "co... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597694 Fri, 13 Jan 2012 05:00:00 +0100 5597694 http://www.medworm.com/index.php?rid=5597693&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247132%26dopt%3DAbstract Authors: McGarvey KM, Queitsch K, Fields S Abstract Most genes for antibiotic resistance present in soil microbes remain unexplored because most environmental microbes cannot be cultured. Only recently has the identification of these genes become feasible through the use of culture-independent methods. We screened a soil metagenomic DNA library in an Escherichia coli host for genes that can confer resistance to kanamycin, gentamicin, rifampin, trimethoprim, chloramphenicol, or tetracycline. The screen revealed 41 genes that encode novel protein variants of eight protein families, including aminoglycoside acetyltransferases, rifampin ADP-ribosyltransferases, dihydrofolate reductases, and transporters. Several proteins of the same family deviate considerably from each other, yet conf... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597693 Fri, 13 Jan 2012 05:00:00 +0100 5597693 http://www.medworm.com/index.php?rid=5597692&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247133%26dopt%3DAbstract Authors: Nikitkova AE, Haase EM, Vickerman MM, Gill SR, Scannapieco FA Abstract Streptococcus gordonii, an important primary colonizer of dental plaque biofilm, specifically binds to salivary amylase via the surface-associated amylase-binding protein A (AbpA). We hypothesized that a function of amylase binding to S. gordonii may be to modulate expression of chromosomal genes, which could influence bacterial survival and persistence in the oral cavity. Gene expression profiling by microarray analysis was performed to detect differentially expressed genes in S. gordonii strain CH1 in response to the binding of purified human salivary amylase as compared to exposure to heat-denatured purified amylase. Selected genes found to be differentially expressed were validated by qRT-PCR. Five ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597692 Fri, 13 Jan 2012 05:00:00 +0100 5597692 http://www.medworm.com/index.php?rid=5597691&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247134%26dopt%3DAbstract Authors: Romano A, Trip H, Lonvaud-Funel A, Lolkema JS, Lucas PM Abstract Biogenic amines are low molecular weight organic bases whose presence in food can result in health problems. The biosynthesis of biogenic amines in fermented foods mostly proceeds through amino acid decarboxylation carried out by lactic acid bacteria (LAB), but not all systems leading to biogenic amine production by LAB have been thoroughly characterized. Here, putative ornithine decarboxylation pathways consisting of a putative ornithine decarboxylase and an amino acid transporter were identified in LAB by strain collection screening and database searches. The decarboxylases were produced in heterologous hosts, purified and characterized in vitro, whereas transporters were heterologously expressed in Lactoco... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597691 Fri, 13 Jan 2012 05:00:00 +0100 5597691 http://www.medworm.com/index.php?rid=5597690&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247135%26dopt%3DAbstract This study was undertaken in order to get some insight on the microbiota which develops and evolves during the manufacture and ripening stages of Oscypek. To this end, we made use of both culturing and the culture-independent methods of PCR-DGGE and pyrosequencing of 16S rRNA gene amplicons. Culture-dependent technique and PCR-DGGE fingerprinting detected the predominant microorganisms in the traditional Oscypek, whereas the next-generation sequencing technique (454 pyrosequencing) revealed greater bacterial diversity. Besides members of the most abundant bacterial genera in dairy products, e.g. Lactococcus, Lactobacillus, Leuconostoc, Streptococcus and Enterococcus, identified by all three methods, other subdominant bacteria belonging to the families Bifidobacteriaceae and Moraxellaceae (... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597690 Fri, 13 Jan 2012 05:00:00 +0100 5597690 http://www.medworm.com/index.php?rid=5597689&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247136%26dopt%3DAbstract In this study, we developed a predictive model for V. vulnificus growth in Eastern oysters (Crassostrea virginica) harvested from Chesapeake Bay, Maryland over a temperature range of 5-30°C, and then validated the model against V. vulnificus growth rates in Eastern and Asian oysters (Crassostrea ariakensis) harvested from Mobile Bay, Alabama and Chesapeake Bay, Virginia, respectively. In the model development studies, V. vulnificus was slowly inactivated at 5 and 10°C with average GR of -0.0045 and -0.0043 log MPN/h, respectively. Estimated average growth rates at 15, 20, 25 and 30°C were 0.022, 0.042, 0.087 and 0.093 log MPN/h, respectively. With respect to Eastern oysters, bias (B(f)) and accuracy factors (A(f)) for model-dependent and -independent data were 1.02 and 1.25, and 1.67 an... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597689 Fri, 13 Jan 2012 05:00:00 +0100 5597689 http://www.medworm.com/index.php?rid=5597688&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247137%26dopt%3DAbstract Authors: Frock AD, Gray SR, Kelly RM Abstract Four hyperthermophilic members of the bacterial genus Thermotoga (T. maritima, T. neapolitana, T. petrophila, and T. sp. RQ2) share a core genome of 1470 open reading frames (ORFs), or about 75% of their genomes. Nonetheless, each species exhibited certain distinguishing features during growth on simple and complex carbohydrates that correlated with genomic inventories of specific ABC sugar transporters and glycoside hydrolases. These differences were consistent with transcriptomic analysis based on a multi-species cDNA microarray. Growth on a mixture of six pentoses and hexoses showed no significant utilization of galactose or mannose by any of the four species. T. maritima and T. neapolitana exhibited similar monosaccharide utilizatio... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597688 Fri, 13 Jan 2012 05:00:00 +0100 5597688 http://www.medworm.com/index.php?rid=5597687&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247138%26dopt%3DAbstract Authors: Wieczorek K, Dmowska K, Osek J Abstract L. monocytogenes isolated from bovine hides and carcasses (n = 812) were mainly of serogroup 1/2a. All strains were positive for internalin genes. Several isolates (72.2%) were resistant to oxacillin or clindamycin (37.0%). These findings indicate that L. monocytogenes of beef origin can be considered as a public health concern. PMID: 22247138 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597687 Fri, 13 Jan 2012 05:00:00 +0100 5597687 http://www.medworm.com/index.php?rid=5597686&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247139%26dopt%3DAbstract Authors: Mortera P, Espariz M, Suárez C, Repizo G, Deutscher J, Alarcón S, Blancato V, Magni C Abstract In E. faecalis, the mae locus is constituted by two putative divergent operons, maePE and maeKR. The first operon encodes a putative H(+)/malate symporter (MaeP) and a malic enzyme (MaeE) previously shown to be essential for malate utilization in this bacterium. The maeKR operon encodes two putative proteins with significant similarity to two-component systems involved in sensing malate and activating its assimilation in bacteria. Our transcriptional and genetic assays showed that maePE and maeKR are induced in response to malate by the response regulator MaeR. In addition, we observed that both operons were partially repressed in the presence of glucose. Accordingly, co-metabo... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597686 Fri, 13 Jan 2012 05:00:00 +0100 5597686 http://www.medworm.com/index.php?rid=5597685&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247140%26dopt%3DAbstract Authors: Barboza-Corona JE, Park HW, Bideshi DK, Federici BA Abstract The cry19A operon of Bacillus thuringiensis subsp. jegathesan encodes two proteins, mosquitocidal Cry19A (ORF1, 75-kDa), and ORF2 (60-kDa) of unknown function. Expression of the cry19A operon in an acrystalliferous strain of B. thuringiensis (4Q7) yielded one small crystal per cell, whereas no crystals were produced when cry19A or orf2 were expressed alone. To determine the function of the ORF2 protein, different combinations of Cry19A, ORF2 and the N- or C-terminal half of Cry1C were synthesized in strain 4Q7. Stable crystalline inclusions of these fusion proteins similar in shape to those in the strain harboring the wild type operon were observed in sporulating cells. Comparative analysis showed that ORF2 share... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597685 Fri, 13 Jan 2012 05:00:00 +0100 5597685 http://www.medworm.com/index.php?rid=5597684&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247141%26dopt%3DAbstract This study explores the hypothesis that non-enzymatic peroxidation of membrane phospholipids is responsible for copper alloy surface killing. Lipid peroxidation was monitored with the TBARS assay. Survival, TBARS levels, and DNA degradation were followed in cells exposed to copper alloy surfaces containing 60 to 99.90% copper or in media containing CuSO(4). In all cases, TBARS levels increased with copper exposure levels. Cells exposed to the highest copper content alloys, C11000 and C24000, exhibited novel characteristics. TBARS increased immediately at a very rapid rate but peaked at about 30 minutes. This peak is associated with the period of most rapid killing, loss in membrane integrity, and DNA degradation. DNA degradation is not the primary cause of copper surface killing. Cells exp... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597684 Fri, 13 Jan 2012 05:00:00 +0100 5597684 http://www.medworm.com/index.php?rid=5597683&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247142%26dopt%3DAbstract This study documents the presence of fecal indicators and bacterial pathogens in sand at 53 California marine beaches using both culture-dependent and -independent (PCR and QPCR) methods. Fecal indicator bacteria were widespread in California beach sand, with Escherichia coli and enterococci detected at 68% and 94% of beaches surveyed, respectively. Somatic coliphages and a Bacteroidales human-specific fecal marker were detected at 43% and 13% of the beaches, respectively. Dry sand samples from almost 30% of the beaches contained at least one of the following pathogens: Salmonella spp., Campylobacter spp., Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) which were detected at 15%, 13%,14%, and 3% of tested beaches, respectively. Fecal indicators and pathogens w... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597683 Fri, 13 Jan 2012 05:00:00 +0100 5597683 http://www.medworm.com/index.php?rid=5597682&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247143%26dopt%3DAbstract Authors: de Bruin A, van der Plaats RQ, de Heer L, Paauwe R, Schimmer B, Vellema P, van Rotterdam BJ, van Duynhoven YT Abstract During large Q fever outbreaks in the Netherlands between 2007 and 2010, dairy goat farms were implicated as the primary source for human Q fever. Transmission of Coxiella burnetii to humans is thought to occur primarily via aerosols, although available data on C. burnetii in aerosols and other environmental matrices are limited.During the outbreak of 2009, 19 dairy goat farms and one dairy sheep farm were selected nationwide to investigate the presence of C. burnetii DNA in vaginal swabs, manure, surface area swabs, milk unit filters, and aerosols. Four of these farms had a positive status during the Coxiella burnetii bulk milk monitoring program in 2009 ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597682 Fri, 13 Jan 2012 05:00:00 +0100 5597682 http://www.medworm.com/index.php?rid=5597681&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247144%26dopt%3DAbstract Authors: Kennedy GM, Morisaki JH, Champion PA Abstract Mycobacterium marinum is a water-borne mycobacterial pathogen. Due to their common niche, protozoa likely represent natural hosts for M. marinum. We demonstrate that the ESX-1 secretion system is required for M. marinum pathogenesis and that M. marinum utilizes actin-based motility in amoebae. Therefore, at least two virulence pathways used by M. marinum in macrophages are conserved during M. marinum infection of amoeba. PMID: 22247144 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597681 Fri, 13 Jan 2012 05:00:00 +0100 5597681 http://www.medworm.com/index.php?rid=5597680&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247145%26dopt%3DAbstract This report describes Mycoplasma contamination of Lawsonia intracellularis cultures that led to the unintended acquisition of a monoclonal antibody against Mycoplasma during the attempted generation of a monoclonal antibody against L. intracellularis. PMID: 22247145 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597680 Fri, 13 Jan 2012 05:00:00 +0100 5597680 http://www.medworm.com/index.php?rid=5597679&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247146%26dopt%3DAbstract Authors: Hernández J, Stedt J, Bonnedahl J, Molin Y, Drobni M, Calisto-Ulloa N, Gomez-Fuentes C, Astorga-España MS, González-Acuña D, Waldenström J, Blomqvist M, Olsen B Abstract Escherichia coli with extended spectrum β-lactamase (ESBL) type CTX-M resistance were isolated from water samples collected close to research stations in Antarctica. The isolates had bla(CTX-M-1) and bla(CTX-M-15) genotypes and sequence types (ST) indicative of a human-associated origin. This is the first record of ESBL-producing enterobacteria from Antarctica. PMID: 22247146 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597679 Fri, 13 Jan 2012 05:00:00 +0100 5597679 http://www.medworm.com/index.php?rid=5597678&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247147%26dopt%3DAbstract Authors: den Bakker HC, Bowen BM, Rodriguez-Rivera LD, Wiedmann M Abstract The bacterial genus Listeria contains both saprotrophic and facultative pathogenic species. A small genome size has been suggested to be associated with the loss of pathogenic potential of L. welshimeri and L. seeligeri. In this paper we present data on the genome of L. monocytogenes strain FSL J1-208, a representative of phylogenetic lineage IV. Although this strain was isolated from a clinical case in a caprine host and has no decreased invasiveness in human intestinal epithelial cells, our analyses show that this strain has one of the smallest Listeria chromosomes reported to date (2.78 Mb). The chromosome contains 2772 protein coding genes, including well-characterized virulence associated genes such as ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597678 Fri, 13 Jan 2012 05:00:00 +0100 5597678 http://www.medworm.com/index.php?rid=5597677&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247148%26dopt%3DAbstract This study demonstrates that mixed S. cerevisiae and C. zemplinina fermentation could be applied in sweet wine fermentation to reduce the production of acetic acid, connected to the S. cerevisiae osmotic stress response. PMID: 22247148 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597677 Fri, 13 Jan 2012 05:00:00 +0100 5597677 http://www.medworm.com/index.php?rid=5597676&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247149%26dopt%3DAbstract Authors: Olvera C, Centeno-Leija S, Ruíz-Leyva P, López-Munguía A Abstract Fructansucrases, including levansucrases and inulosucrases, are enzymes that synthesize fructose polymers from sucrose by the direct transfer of the fructosyl moiety to a growing polymer chain. These enzymes, particularly the single domain fructansucrases, also possess an important hydrolytic activity, which may account for as much as 70 to 80% of substrate conversion, depending on reaction conditions. In this research, we report the construction of four chimeric levansucrases from SacB, a single domain levansucrase produced by B. subtilis. Based on observations derived from the effect of domain deletion in both multidomain fructan- and glucansucrases, we attached different extensions to SacB. These exten... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597676 Fri, 13 Jan 2012 05:00:00 +0100 5597676 http://www.medworm.com/index.php?rid=5597675&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247150%26dopt%3DAbstract In this study, the airborne bacterial community at a subway station in Norway was characterized (concentration level, diversity, virulence- and survival-associated properties). Additionally, a SASS 3100 high-volume air sampler and a MALDI-ToF MS-based isolate screening procedure was used for the first time in such studies. The daytime level of airborne bacteria at the station was higher than nighttime and outdoor levels, and the relative bacterial spore number was higher in outdoor air than at the station. The bacterial content, particle concentration and size-distribution were stable within each environment throughout the study (May - September 2010). The majority of airborne bacteria belonged to Bacillus, Micrococcus and Staphylococcus, but a total of 37 different genera were identified ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597675 Fri, 13 Jan 2012 05:00:00 +0100 5597675 http://www.medworm.com/index.php?rid=5597674&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247151%26dopt%3DAbstract This study is the special interest considering the exposure of a large number of humans and animals to this waterborne protozoan, highly tumorigenic when inoculated in a rodent model. PMID: 22247151 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597674 Fri, 13 Jan 2012 05:00:00 +0100 5597674 http://www.medworm.com/index.php?rid=5597673&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247152%26dopt%3DAbstract Authors: Fink RC, Black E, Hou Z, Sugawara M, Sadowsky MJ, Diez-Gonzalez F Abstract An increasing number of outbreaks of gastroenteritis recently caused by Escherichia coli O157:H7 have been linked to the consumption of leafy green vegetables. Although it is known that E. coli survives and grows in the phyllosphere of lettuce plants, the molecular mechanisms by which this bacterium associates with plants are largely unknown. The goal of this study was to identify E. coli genes relevant to its interaction, survival, or attachment to lettuce leaf surfaces comparing E. coli K12, a model system, and E. coli O157:H7, a pathogen associated with a large number of outbreaks. Using microarrays, we found that upon interaction with intact leaves 10.1% and 8.7% of the 3,798 shared genes were d... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597673 Fri, 13 Jan 2012 05:00:00 +0100 5597673 http://www.medworm.com/index.php?rid=5597672&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247153%26dopt%3DAbstract Authors: Nenonen NP, Hannoun C, Larsson CU, Bergström T Abstract Marked Norovirus (NoV) diversity was detected in patient samples from a large community outbreak of gastroenteritis with waterborne epidemiology affecting approximately 2400 people. NoV was detected in 33 of 50 patient samples examined by group-specific real-time RT-PCR. NoV genotype (G)I strains predominated in 31 patients with mixed GI infections occurring in five of these patients. Sequence-analysis of RNA-dependent polymerase-N/S capsid-coding regions (approx. 900 nt) confirmed dominance of GI strains (n=36). Strains of NoV GI.4 (n=21), and GI.7 (n=9) were identified, but 6 strains required full capsid amino acid analyses (530-550 aa,) before definitive genotyping based on control sequencing of cloned amplicons. ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597672 Fri, 13 Jan 2012 05:00:00 +0100 5597672 http://www.medworm.com/index.php?rid=5597671&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247154%26dopt%3DAbstract Authors: Deutsch SM, Parayre S, Bouchoux A, Guyomarc'h F, Dewulf J, Dols-Lafargue M, Baglinière F, Cousin FJ, Falentin H, Jan G, Foligné B Abstract Propionibacterium freudenreichii is a bacterial species found in Swiss type cheeses and is also considered for its health properties. The main claimed effect is the bifidogenic property. Recently, some strains were shown to display other interesting probiotic potentialities like anti-inflammatory properties. About 30% of strains were shown to produce a surface exopolysaccharide (EPS) composed of (1→3,1→2)-β-D-glucan, due to a single gene named gtfF. We hypothesized that functional properties of P. freudenreichii strains, and their anti-inflammatory properties, could be linked to β-glucan presence. To evaluate this hypothesis, gt... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597671 Fri, 13 Jan 2012 05:00:00 +0100 5597671 http://www.medworm.com/index.php?rid=5597670&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247155%26dopt%3DAbstract Authors: Zhao S, Blickenstaff K, Bodeis-Jones S, Gaines SA, Tong E, McDermott PF Abstract Escherichia coli were recovered from the National Antimicrobial Resistance Monitoring System retail meat program and examined for antimicrobial susceptibility. Retail meat samples (N= 11,921) from four U.S. states collected during 2002-2008 were analyzed, consisting of 2,988 chicken breast, 2,942 ground turkey, 2,991 ground beef and 3,000 pork chops. A total of 8,286 E. coli were recovered. Most chicken (83.5%) and turkey (82.0%) were contaminated with the organism, followed by beef (68.9%) and pork (44.0%). Resistance to tetracycline was most common (50.3%), followed by streptomycin (34.6%), sulfamethoxazole/sulfisoxazole (31.6%), ampicillin (22.5%), gentamicin (18.6%), kanamycin (8.4%), amox... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597670 Fri, 13 Jan 2012 05:00:00 +0100 5597670 http://www.medworm.com/index.php?rid=5597669&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247156%26dopt%3DAbstract Authors: Neetoo H, Lu Y, Wu C, Chen H Abstract Green onions grown in soil and hydroponic media contaminated with E. coli O157:H7 and Salmonella were found to uptake the pathogens in their roots, bulbs, stems and leaves. Pressure-treatment at 400-500 MPa for 2 min at 20-40°C eliminated both pathogens that were internalized within green onions during plant growth. PMID: 22247156 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597669 Fri, 13 Jan 2012 05:00:00 +0100 5597669 http://www.medworm.com/index.php?rid=5597668&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247157%26dopt%3DAbstract In conclusion, our data show that phenotypic switching in P. brassicacearum results from mutations in the gacS/gacA system. PMID: 22247157 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597668 Fri, 13 Jan 2012 05:00:00 +0100 5597668 http://www.medworm.com/index.php?rid=5597667&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247158%26dopt%3DAbstract Authors: Kim JW, Dutta V, Elhanafi D, Lee S, Osborne JA, Kathariou S Abstract Listeria monocytogenes epidemic clone II (ECII) strains are unusual in being completely resistant to phage when grown at low temperatures (≤30°C). In the current study we constructed and characterized a mariner-based mutant (J46C) of the ECII strain H7550-Cd(S) that lacked temperature-dependent resistance to phage. The transposon was localized in LMOh7858_2753 (ORF 2753), a member of a 12-ORF genomic island unique to ECII strains. ORF 2753 and ORF 2754 exhibited homologies to restriction endonucleases and methyltransferases associated with type II restriction restriction-modification (RM) systems. In silico-based predictions of the recognition site for this putative RM system were supported by resistan... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597667 Fri, 13 Jan 2012 05:00:00 +0100 5597667 http://www.medworm.com/index.php?rid=5597666&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247159%26dopt%3DAbstract Authors: Cao Y, He S, Zhou Z, Zhang M, Mao W, Zhang H, Yao B Abstract N-Acylated homoserine lactone (AHL) lactonases are capable to degrade signal molecules involved in bacterial quorum sensing and therefore represent a new approach to control bacterial infection. Herein a gene responsible for AHL lactonase activity of Bacillus sp. AI96, 753 base pairs in length, was cloned and then expressed in Escherichia coli. The deduced amino acid sequence (AiiA-AI96) is most similar to those of other Bacillus spp. AHL lactonases (∼80% sequence identity) and was consequently categorized as a member of the metallo-β-lactamase superfamily. AiiA-AI96 maintains ∼100% of its activity at 10-40°C, pH 8.0, and it is very stable at 70°C, pH 8.0 for at least 1 h; no other Bacillus AHL lactonase h... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597666 Fri, 13 Jan 2012 05:00:00 +0100 5597666 http://www.medworm.com/index.php?rid=5597665&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247160%26dopt%3DAbstract Authors: Velazquez-Roman J, León-Sicairos N, Flores-Villaseñor H, Villafaña-Rauda S, Canizalez-Roman A Abstract In 2004, more than 1230 cases of gastroenteritis due to pandemic O3:K6 strains of Vibrio parahaemolyticus were reported in southern Sinaloa, a state in Northwestern Mexico. Recurrent sporadic cases arose from 2004 to 2010, spreading from the south to the north. In the present study, Vibrio parahaemolyticus was detected in both environmental samples and clinical cases along the Pacific Coast of Sinaloa during 2004 to 2010. An evaluation was made of the serotypes, distribution of virulence genes, and presence of pandemic O3:K6 strains. A total of 144 strains were isolated from environmental samples (from sediment, seawater and shrimp), and 154 clinical strains were isola... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597665 Fri, 13 Jan 2012 05:00:00 +0100 5597665 http://www.medworm.com/index.php?rid=5597664&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247161%26dopt%3DAbstract Authors: Foulongne-Oriol M, Rodier A, Savoie JM Abstract Dry bubble, caused by Lecanicillium fungicola, is one of the most detrimental diseases affecting the button mushroom cultivation. In a previous study, we have demonstrated that breeding for resistance to this pathogen is quite challenging due to its quantitative inheritance. A second generation hybrids progeny derived from an intervarietal cross between a wild strain and a commercial cultivar was characterized for L. fungicola resistance under artificial inoculation in three independent experiments. Quantitative Trait Locus (QTL) analysis was used to determine the location, number and effects of genomic regions associated with dry bubble resistance. Four traits related to resistance were analysed. Two to four QTL were detecte... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597664 Fri, 13 Jan 2012 05:00:00 +0100 5597664 http://www.medworm.com/index.php?rid=5597663&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247162%26dopt%3DAbstract Authors: Wey JK, Jürgens K, Weitere M Abstract The effects of protozoa (heterotrophic flagellates and ciliates) on the morphology and community composition of bacterial biofilms were tested under natural background conditions by applying size fractionation in a river bypass system. Confocal Laser Scanning Microscopy (CLSM) was used to monitor the morphological structure of the biofilm and fingerprinting methods (Single Stranded Conformation Polymorphism [SSCP], Denaturing Gradient Gel Electrophoresis [DGGE]) were utilized to assess changes in bacterial community composition. Season and internal population dynamics had a greater influence on the bacterial biofilm than the presence of protozoa. Within this general framework, bacterial area coverage and microcolony abundance were nev... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597663 Fri, 13 Jan 2012 05:00:00 +0100 5597663 http://www.medworm.com/index.php?rid=5597662&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247163%26dopt%3DAbstract Authors: Herrmann S, Siegl T, Luzhetska M, Petzke L, Jilg C, Welle E, Erb A, Leadlay PF, Bechthold A, Luzhetskyy A Abstract The feasibility of using technologies based on site-specific recombination in actinomycetes was shown several years ago. Despite their huge potential, these technologies mostly have been used for simple marker removal from a chromosome. In this paper, we present different site-specific recombination strategies for genome engineering in several actinomycetes belonging to the genera Streptomyces, Micromonospora and Saccharothrix. Two different systems based on Cre/loxP and Dre/rox have been utilised for numerous applications. The activity of the Cre recombinase on the heterospecific loxLE and loxRE sites was similar to its activity on wild type loxP sites. Moreo... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597662 Fri, 13 Jan 2012 05:00:00 +0100 5597662 http://www.medworm.com/index.php?rid=5597661&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247164%26dopt%3DAbstract This study compares culture-dependent and qPCR methods to successfully quantify a complex fungal microbiota on a model-curd simulating Camembert-type cheese. PMID: 22247164 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597661 Fri, 13 Jan 2012 05:00:00 +0100 5597661 http://www.medworm.com/index.php?rid=5597660&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247165%26dopt%3DAbstract This study has provided an excellent candidate for the mechanistic study of sulfonylurea herbicides' metabolism and detoxification through de-esterification, construction of sulfonylurea herbicide-resistant transgenic crops, and bioremediation of sulfonylurea herbicide-contaminated environments. PMID: 22247165 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597660 Fri, 13 Jan 2012 05:00:00 +0100 5597660 http://www.medworm.com/index.php?rid=5597659&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247166%26dopt%3DAbstract This article defines the term surrogate as an organism, particle, or substance to study the fate of a pathogen in a specific environment. Pathogenic organisms, non-pathogenic organisms, and innocuous particles have been used as surrogates for a variety of purposes including studies on survival, transport as well as for methods development and as "indicators" of certain conditions. This article develops a qualitative surrogate attribute prioritization process and allows investigators to select a surrogate by systematically detailing the experimental process and prioritizing attributes. The results are described through the use of case studies of various laboratories that have used this process. This article also discusses the history of surrogate and microbial indicator use, and outlines th... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597659 Fri, 13 Jan 2012 05:00:00 +0100 5597659 http://www.medworm.com/index.php?rid=5597658&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247167%26dopt%3DAbstract Authors: Nygaard H, Modahl I, Myrmel M Abstract IPNV (serotype Sp) was exposed to temperatures from 60 to 90°C in a medium mimicking the water soluble phase of hydrolyzed fish by-products. D-values ranged from 290 to 0.5 min and the z-value was approximately 9.8°C. Addition of formic acid to pH 4 did not enhance heat inactivation. Predicted inactivation effects at different temperature-time combinations are provided. PMID: 22247167 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597658 Fri, 13 Jan 2012 05:00:00 +0100 5597658 http://www.medworm.com/index.php?rid=5597602&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247168%26dopt%3DAbstract Authors: Kampmann K, Ratering S, Kramer I, Schmidt M, Zerr W, Schnell S Abstract In the present study, bacterial communities in 200 l biogas reactors containing liquid manure consecutively fed with casein, starch and cream were investigated over a period of up to 33 days. A 16S rRNA gene clone library identified Bacteroidetes and Firmicutes with 58.9 % and 30.1 %, respectively, as most abundant bacterial groups in the starting material. Community development of both groups was monitored by real-time PCR and single strand conformation polymorphism (SSCP) analysis. The Firmicutes and Bacteroidetes communities were unexpectedly stable and hardly influenced by batch feeding events. Continuous feeding of starch led to community shifts that nevertheless contributed to a stable reactor pe... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597602 Fri, 13 Jan 2012 05:00:00 +0100 5597602 http://www.medworm.com/index.php?rid=5597601&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247169%26dopt%3DAbstract Authors: Herzog B, Wirth R Abstract The swimming behavior of Bacteria has been studied extensively, at least for some species like Escherichia coli. In contrast alomost no data have been published for Archaea in this respect. In a systematic study we asked how the archaeal model organisms Halobacterium salinarum, Methanococcus voltae, Methanococcus maripaludis, Methanocaldococcus jannaschii, Methanocaldococcus villosus, Pyrococcus furiosus and Sulfolobus acidocaldarius swim and which swimming behavior they exhibit. The two Euryarchaeota M. jannaschii and M. villosus were found to be by far the fastest organisms reported up to now, if speed is measured in bps (bodies per second). Their swimming speeds, with close to 400 and 500 bps, are much higher than that of the bacterium E. coli... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597601 Fri, 13 Jan 2012 05:00:00 +0100 5597601 http://www.medworm.com/index.php?rid=5597600&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247170%26dopt%3DAbstract Authors: Norberg S, O' Connor PM, Stanton C, Ross RP, Hill C, Fitzgerald GF, Cotter PD Abstract Caseicin A and B are low molecular weight antimicrobial peptides which are released by proteolytic digestion of sodium caseinate. Caseicin A (IKHQGLPQE) is a nine amino acid, cationic peptide and Caseicin B (VLNENLLR) is a neutral eight amino acid peptide, both of which have previously been shown to exhibit antibacterial activity against a number of pathogens including Cronobacter sakazakii. Previously, four variants of each of caseicin which differed subtly from their natural counterparts were generated by peptide synthesis. Antimicrobial activity assays in this study revealed that the importance of a number of the residues within the peptides was dependent on the strain being targeted.... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597600 Fri, 13 Jan 2012 05:00:00 +0100 5597600 http://www.medworm.com/index.php?rid=5597599&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247171%26dopt%3DAbstract Authors: Santos AL, Oliveira V, Baptista I, Henriques I, Gomes NC, Almeida A, Correia A, Cunha A Abstract The effects of UV radiation (UVR) on estuarine bacterioneuston and bacterioplankton were assessed in microcosms experiments. Bacterial abundance and DNA synthesis were more affected in bacterioplankton. Protein synthesis was more inhibited in bacterioneuston. Community analysis indicated that UVR has the potential to select resistant bacteria (e.g. Gammaproteobacteria), particularly abundant in bacterioneuston. PMID: 22247171 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597599 Fri, 13 Jan 2012 05:00:00 +0100 5597599 http://www.medworm.com/index.php?rid=5597598&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247172%26dopt%3DAbstract Authors: Sun MM, Sun J, Qiu JW, Jing H, Liu H Abstract The persistent bloom of the brown tide alga Aureoumbra lagunensis has been reported in coastal embayments along southern Texas, but the molecular mechanisms that sustain such algal bloom is unknown. We compared the proteome and physiological parameters of A. lagunensis grown in P-depleted, P-and N-depleted and nutrient-replete cultures. For the proteomic analysis, samples from three conditions were subjected to two-dimensional electrophoresis and tandem mass spectrometry analysis. Because of the paucity of genomic resources in this species, de novo cross-species protein search was used to identify the differentially expressed proteins, which revealed their involvement in several key biological processes, such as chlorophyll syn... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597598 Fri, 13 Jan 2012 05:00:00 +0100 5597598 http://www.medworm.com/index.php?rid=5597597&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247173%26dopt%3DAbstract Authors: Hanna LF, Matthews TD, Dinsdale EA, Hasty D, Edwards RA Abstract Phages are a primary driving force behind the evolution of bacterial pathogens by transferring a variety of virulence genes into their hosts. Similar to other bacterial genomes, the Salmonella enterica serovar Enteritidis LK5 genome contains several regions that are homologous to phages. Although genomic analyses demonstrated the presence of prophages, it was unable to confirm which phage elements within the genome were viable. Genetic markers were used to tag one of the prophages in the genome to allow monitoring of phage induction. Commonly used laboratory strains of Salmonella were resistant to phage infection, and therefore a rapid screen was developed to identify susceptible hosts. This approach showed t... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597597 Fri, 13 Jan 2012 05:00:00 +0100 5597597 http://www.medworm.com/index.php?rid=5597596&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247174%26dopt%3DAbstract Authors: Shao L, Zi J, Zeng J, Zhan J Abstract The 53-kb biosynthetic gene cluster for the novel anti-cholesterol natural product herboxidiene was identified from Streptomyces chromofuscus ATCC 49982 by genome sequencing and gene inactivation. In addition to herboxidiene, a biosynthetic intermediate, 18-deoxy-herboxidiene, was also isolated from the fermentation broth of S. chromofuscus ATCC 49982 as a minor metabolite. PMID: 22247174 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597596 Fri, 13 Jan 2012 05:00:00 +0100 5597596 http://www.medworm.com/index.php?rid=5597595&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247175%26dopt%3DAbstract Authors: Reunanen J, von Ossowski I, Hendrickx AP, Palva A, de Vos WM Abstract Lactobacillus rhamnosus GG is a human intestinal isolate studied intensively because of its probiotic properties. We have previously shown L. rhamnosus GG to produce proteinaceous pili, that had earlier been observed only in Gram-positive pathogens. These pili were found to be encoded by the spaCBA gene cluster, and the pilus-associated SpaC pilin was shown to confer the cells with mucus binding ability. In addition to the spaCBA cluster, another putative pilus cluster, spaFED, was predicted from the L. rhamnosus GG genome sequence. Herein, we show that only SpaCBA pili are produced by L. rhamnosus, and describe a detailed analysis of cell wall-associated and affinity purified SpaCBA pili by Western blot... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597595 Fri, 13 Jan 2012 05:00:00 +0100 5597595 http://www.medworm.com/index.php?rid=5597594&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247176%26dopt%3DAbstract Authors: Tang JD, Perkins AD, Sonstegard TS, Schroeder SG, Burgess SC, Diehl SV Abstract The feasibility of short read sequencing for genomic analysis was demonstrated for Fibroporia radiculosa, a copper-tolerant fungus that causes brown rot decay of wood. The effect of read quality on genomic assembly was assessed by filtering Illumina GAIIx reads from a single run of a paired-end library (75 nt read length, 300 bp fragment size) to three different stringency levels, and then assembling each dataset with Velvet. A simple approach was devised to determine which filter stringency was "best". Venn diagrams identified the regions containing reads that were used in an assembly, but were of low enough quality to be removed by a filter. By plotting base quality histograms of reads in thi... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597594 Fri, 13 Jan 2012 05:00:00 +0100 5597594 http://www.medworm.com/index.php?rid=5597593&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247177%26dopt%3DAbstract Authors: Stone W, Jones BL, Wilsenach J, Botha A Abstract Candida albicans is well-studied within the human host; however, identifying environmental reservoirs of pathogens is epidemiologically valuable for disease management. Oxygen-limited, carbohydrate-rich zones of wetlands, to which sewage-borne C. albicans is often exposed, are characteristically similar to the gastrointestinal reservoir. Consequently, using qRT-PCR and GC-MS we demonstrated that oxygen-limited zones in polluted wetlands may act as potential reservoirs of C. albicans. PMID: 22247177 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597593 Fri, 13 Jan 2012 05:00:00 +0100 5597593 http://www.medworm.com/index.php?rid=5597592&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22247178%26dopt%3DAbstract We report the biochemical and mutational analyses of Caldicellulosiruptor bescii Cel9B/Man5A (CbCel9B/Man5A), a highly thermophilic enzyme. As one of the highly secreted proteins of C. bescii, the enzyme is likely to be critical to nutrient acquisition by the bacterium. CbCel9B/Man5A is a modular protein composed of three carbohydrate-binding modules flanked at the N-terminus and the C-terminus by a glycoside hydrolase family 9 (GH9) module and a GH5 module, respectively. Based on truncational analysis of the polypeptide, the cellulase and mannanase activities within CbCel9B/Man5A were assigned to the N- and C-terminal modules, respectively. CbCel9B/Man5A and its truncational mutants, in general, exhibited a pH optimum of ∼5.5 and temperature optimum of 85 °C. However, at this temperatu... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5597592 Fri, 13 Jan 2012 05:00:00 +0100 5597592 http://www.medworm.com/index.php?rid=5577664&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22226947%26dopt%3DAbstract Authors: Ojima T, Saburi W, Yamamoto T, Kudo T Abstract An α-glucosidase (HaG) with the following unique properties was isolated from Halomonas sp. H11 strain: 1) high transglucosylation activity; 2) activation by monovalent cations; and 3) very narrow substrate specificity. The molecular mass of the purified HaG was estimated at 58 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). HaG showed high hydrolytic activities toward maltose, sucrose, and p-nitrophenyl α-d-glucoside (pNPG), but to almost no other disaccharides or malto-oligosaccharides higher than trisaccharides. HaG showed optimum activity to maltose at 30°C and pH 6.5. Monovalent cations such as K(+), Rb(+), Cs(+), and NH(4)(+) increased the enzymatic activity to 2-9-fold of the original act... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577664 Fri, 06 Jan 2012 05:00:00 +0100 5577664 http://www.medworm.com/index.php?rid=5577663&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22226948%26dopt%3DAbstract Authors: Marcos MS, Lozada M, Di Marzio WD, Dionisi HM Abstract Novel polycyclic aromatic hydrocarbon dioxygenase gene variants were present in similar or higher abundances than phnA1 from Cycloclasticus spp., at a chronically-polluted Subantarctic coastal marine environment in Patagonia. These novel gene variants were detected over a six year time-span and were also present in sediments from Patagonian temperate sites. PMID: 22226948 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577663 Fri, 06 Jan 2012 05:00:00 +0100 5577663 http://www.medworm.com/index.php?rid=5577662&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22226949%26dopt%3DAbstract Authors: Ingalls AE, Huguet C, Truxal LT Abstract There is great interest in membrane lipids of archaea (glycerol dialkyl glycerol tetraethers, GDGTs) as tracers of archaeal biomass because of their utility as paleoproxies and because of the biogeochemical importance of archaea. While core GDGTs (formed by hydrolysis of polar head groups of intact GDGTs after cell death), are appropriate for paleostudies, they have also been used to trace archaeal populations. Also, despite the small size (0.2×0.7μm) of cultivated marine archaea, 0.7μm GFF filters are typically used to collect GDGTs from natural waters. We quantified both core and intact GDGTs in free-living (0.2-0.7 μm), suspended (0.7-60 μm) and aggregate (>60 μm) particle size fractions in the Puget Sound (Washington St... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577662 Fri, 06 Jan 2012 05:00:00 +0100 5577662 http://www.medworm.com/index.php?rid=5577661&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22226950%26dopt%3DAbstract The objectives of this study were to compare the host specificity of a previous C. marimammalium qPCR assay (gull2) with that of the new markers and to examine the presence of the three gull markers in environmental water samples from different geographic locations. Of the 255 gull fecal samples tested, 86% were positive for gull2 and gull4, whereas only 28% were positive with gull3. Low prevalence and abundance of tested gull markers (0.6-15%) were observed in fecal samples from six non-avian species (n=180), whereas the assays cross-reacted to some extent (13-31%) with other (non-gull) avian fecal samples. The gull3 assay was positive against fecal samples from 11 of 15 avian species including gull. Of the presumed gull-impacted water samples (n=349), 86%, 59%, and 91% were positive for ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577661 Fri, 06 Jan 2012 05:00:00 +0100 5577661 http://www.medworm.com/index.php?rid=5577660&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22226951%26dopt%3DAbstract Authors: Weissman SJ, Johnson JR, Tchesnokova V, Billig M, Dykhuizen D, Riddel K, Rogers P, Qin X, Butler-Wu S, Cookson BT, Fang F, Scholes D, Chattopadhyay S, Sokurenko E Abstract Multi-locus sequence typing (MLST) is usually based on sequencing 5 to 8 housekeeping loci in the bacterial chromosome and has provided detailed descriptions of the population structure of bacterial species important to human health. However, even strains with identical MLST profiles (known as sequence types, or STs) may possess distinct genotypes, which enable different eco- or pathotypic lifestyles. Here we describe a two-locus, sequence-based typing scheme for Escherichia coli that utilizes a 489-nt internal fragment of fimH (encoding the type 1 fimbrial adhesin) and the 469-nt internal fumC fragment ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577660 Fri, 06 Jan 2012 05:00:00 +0100 5577660 http://www.medworm.com/index.php?rid=5577659&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22226952%26dopt%3DAbstract In this study we describe two proteins from endophytic bacteria that display activity in the cleavage and the synthesis reaction of (R)-mandelonitrile with up to 74% conversion of benzaldehyde (ee 89%). Both showed high similarity to proteins of the cupin superfamily which so far were not known to exhibit HNL activity. PMID: 22226952 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577659 Fri, 06 Jan 2012 05:00:00 +0100 5577659 http://www.medworm.com/index.php?rid=5577658&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22226953%26dopt%3DAbstract Authors: Bassegoda A, Pastor FI, Diaz P Abstract Bacterial lipases constitute the most important group of biocatalysts for synthetic organic chemistry. Accordingly, there is substantial interest in developing new valuable lipases. Considering the lack of information concerning the lipases of the genus Rhodococcus and taking into account the interest raised by the enzymes produced by actinomycetes, a search for putative lipase-encoding genes from Rhodococcus sp. CR-53 was performed. We isolated, cloned, purified, and characterized LipR, the first lipase described from the genus Rhodococcus. LipR is a mesophilic enzyme showing preference for medium chain length acyl groups without showing interfacial activation. It displays good long-term stability and high tolerance for the presence... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577658 Fri, 06 Jan 2012 05:00:00 +0100 5577658 http://www.medworm.com/index.php?rid=5577657&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22226954%26dopt%3DAbstract Authors: McDevitt JJ, Rudnick SN, Radonovich LJ Abstract Person-to-person transmission of influenza virus, especially in the event of a pandemic caused by a highly virulent strain of influenza, such as H5N1 avian influenza, is of great concern due to widespread mortality and morbidity. The consequences of seasonal influenza are also substantial. Because airborne transmission appears to play a role with influenza, public health interventions should focus on preventing or interrupting this process. Air disinfection via upper-room 254 nm germicidal ultraviolet (UVC) light in public buildings may be able to reduce influenza transmission via the airborne route. We characterized the susceptibility of influenza A (H1N1, PR-8) aerosols to UVC light using a benchtop chamber equipped with an... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577657 Fri, 06 Jan 2012 05:00:00 +0100 5577657 http://www.medworm.com/index.php?rid=5577656&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22226955%26dopt%3DAbstract Authors: Buse HY, Ashbolt NJ Abstract Here we present the first attempt to quantify L. pneumophila cell numbers within individual amoebae hosts that may be released into engineered water systems. The maximum numbers of culturable L. pneumophila cells grown within Acanthamoeba polyphaga and Naegleria fowleri were 1348 (mean 329) and 385 (mean 44) CFU trophozoite(-1), respectively. PMID: 22226955 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577656 Fri, 06 Jan 2012 05:00:00 +0100 5577656 http://www.medworm.com/index.php?rid=5577655&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22226956%26dopt%3DAbstract Authors: Taulé C, Zabaleta M, Mareque C, Platero R, Sanjurjo L, Sicardi M, Frioni L, Battistoni F, Fabiano E Abstract Among the leguminous trees natives to Uruguay Parapiptadenia rigida (Angico), a Mimosoideae legume, is one of the most promising species for agroforestry. Like many other legumes, it is able to establish symbiotic associations with rhizobia and belongs to the group known as "Nitrogen Fixing Trees", which are major components of agroforestry systems. Information about rhizobial symbionts for this genus is scarce, and thus the aim of this work was to identify and characterize rhizobia associated with P. rigida. A collection of Angico-nodulating isolates was obtained and 47 isolates were selected for genetic studies. According to ERIC-PCR patterns and RFLP analysis of... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577655 Fri, 06 Jan 2012 05:00:00 +0100 5577655 http://www.medworm.com/index.php?rid=5577684&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210204%26dopt%3DAbstract Authors: Isabel S, Boissinot M, Charlebois I, Fauvel CM, Shi LE, Lévesque JC, Paquin AT, Bastien M, Stewart G, Leblanc E, Sato S, Bergeron MG Abstract Suspicious powders and other samples need to be analyzed frequently for biothreat agents by authorities to assess environmental safety. Numerous nucleic acid detection technologies have been developed to detect and identify biowarfare agents in a timely fashion. Extracting microbial nucleic acids from a wide variety of powdery and environmental samples to obtain a quality level adequate for these technologies still remains a technical challenge. We aimed to develop a rapid and versatile method to separate bacteria from these samples and then extract their microbial DNA. Bacillus atrophaeus subspecies globigii was used as a simulant ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577684 Fri, 30 Dec 2011 05:00:00 +0100 5577684 http://www.medworm.com/index.php?rid=5577683&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210205%26dopt%3DAbstract In this study, we examined virus-like particle (VLP) abundances in planktonic and attached microbial communities, which occur in physical and chemical gradients in both deep and shallow submarine hydrothermal environments: mixing waters between hydrothermal fluids and ambient seawater and dense microbial communities attached to chimney surface areas or macrofauna bodies and colonies. We found that viruses were widely distributed in a variety of hydrothermal microbial habitats with the exception of the interior parts of hydrothermal chimney structures. The VLP abundance and VLP-to-prokaryote ratio (VPR) in the planktonic habitats increased as the ratio of hydrothermal fluid to mixing water increased. On the other hand, the VLP abundance in attached microbial communities was significantly an... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577683 Fri, 30 Dec 2011 05:00:00 +0100 5577683 http://www.medworm.com/index.php?rid=5577682&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210206%26dopt%3DAbstract Authors: Camarero S, Pardo I, Cañas AI, Molina P, Record E, Martínez AT, Martínez MJ, Alcalde M Abstract While the Pycnoporus cinnabarinus Laccase (PcL) is one of the most promising high redox potential enzymes for environmental biocatalysis, its practical use has to date remained limited due to the lack of directed evolution platforms with which to improve its features. Here, we describe the construction of a PcL fusion gene and the optimization of conditions to induce its functional expression in Saccharomyces cerevisiae, facilitating its directed evolution and semi-rational engineering. The native PcL signal peptide was replaced by the α-factor prepro-leader and this construct was subjected to six rounds of evolution coupled to a multi-screening assay based on the oxidation ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577682 Fri, 30 Dec 2011 05:00:00 +0100 5577682 http://www.medworm.com/index.php?rid=5577681&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210207%26dopt%3DAbstract Authors: Schumann S, Alpert C, Engst W, Loh G, Blaut M Abstract To identify Escherichia coli proteins involved in adaptation to intestinal inflammation, mice were monoassociated with the colitogenic E. coli UNC (UNC) or with the probiotic E. coli Nissle (EcN). Intestinal inflammation was induced by treating the mice with 3.5% dextran sodium sulfate (DSS). Differentially expressed proteins were identified by two-dimensional difference gel electrophoresis in E. coli collected from cecal contents. In both strains acute inflammation led to down-regulation of pathways involved in carbohydrate breakdown and energy generation. Accordingly, DSS-treated mice had lower concentrations of bacterial fermentation products in their cecal contents than control mice. Differentially expressed protei... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577681 Fri, 30 Dec 2011 05:00:00 +0100 5577681 http://www.medworm.com/index.php?rid=5577680&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210208%26dopt%3DAbstract Authors: Chon JW, Hyeon JY, Lim JH, Kim JH, Song KY, Seo KH Abstract Modified charcoal-cefoperazone-deoxycholate agar (mCCDA) was improved by supplementation with a high concentration of polymyxin B. The ability of the supplemented medium to isolate Campylobacter jejuni and C. coli from chicken carcass rinse was compared to that of Campy-Cefex agar and mCCDA. Modification of mCCDA with increased polymyxin B yielded significantly (p < 0.05) better isolation rate and selectivity than those achieved on using Campy-Cefex agar and mCCDA. PMID: 22210208 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577680 Fri, 30 Dec 2011 05:00:00 +0100 5577680 http://www.medworm.com/index.php?rid=5577679&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210209%26dopt%3DAbstract Authors: Rump LV, Bodeis-Jones S, Abbott J, Zhao S, Kase J, Lorenz S, Fischer M, Brown E, Meng J Abstract Escherichia coli O104 from different sources in the United States were examined for virulence genes typical for enterohemorrhagic E. coli and those identified in the O104:H4 isolate associated with the 2011 German outbreak. Unexpected presence of virulence markers in these isolates highlights the importance of screening unusual and potentially pathogenic Shiga toxin-producing E. coli serotypes. PMID: 22210209 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577679 Fri, 30 Dec 2011 05:00:00 +0100 5577679 http://www.medworm.com/index.php?rid=5577678&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210210%26dopt%3DAbstract Authors: You C, Zhang XZ, Sathitsuksanoh N, Lynd LR, Zhang YH Abstract A cellulosome-microbe complex was assembled ex vivo on the surface of Bacillus subtilis displaying a mini-scaffoldin that can bind with three dockerin-containing cellulase components - an endoglucanase Cel5, a processive endoglucanase Cel9, and a cellobiohydrolase Cel48. The hydrolysis performance of the synthetic cellulosome bound to living cells, the synthetic cellulosome, a non-complexed cellulase mixture with the same catalytic components, and a commercial fungal enzyme mixture was investigated on low-accessibility recalcitrant Avicel and high-accessibility regenerated amorphous cellulose. The cell-bound cellulosome exhibited 4.5- and 2.3-fold higher hydrolysis ability than cell-free cellulosome on Avicel an... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577678 Fri, 30 Dec 2011 05:00:00 +0100 5577678 http://www.medworm.com/index.php?rid=5577677&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210211%26dopt%3DAbstract Authors: Al Dahouk S, Hofer E, Tomaso H, Vergnaud G, Le Flèche P, Cloeckaert A, Koylass MS, Whatmore AM, Nöckler K, Scholz HC Abstract Brucellosis is one of the major bacterial zoonoses worldwide. In the last decade, an increasing number of atypical Brucella strains and species have been described. Brucella microti in particular attracted attention because this species not only infects mammalian hosts but also persists in soil. An environmental reservoir may pose a new public health risk leading to the re-emergence of brucellosis. In a polyphasic approach, comprising conventional microbiological, extensive biochemical and molecular techniques, all currently available B. microti strains were characterized.Although differing in their natural habitat and host preference, B. microti ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577677 Fri, 30 Dec 2011 05:00:00 +0100 5577677 http://www.medworm.com/index.php?rid=5577676&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210212%26dopt%3DAbstract Authors: Dang TC, Fujii M, Rose AL, Bligh M, Waite TD Abstract A continuous culturing system (chemostat) made of metal-free materials was successfully developed and used to maintain Fe-limited cultures of Microcystis aeruginosa PCC7806 at nanomolar iron (Fe) concentrations (20-50 nM total Fe). EDTA was used to maintain Fe in solution with bioavailable Fe controlled by absorption of light by the ferric EDTA complex and resultant reduction of Fe(III) to Fe(II). A kinetic model describing Fe transformations and biological uptake was applied to determine the biologically available form of Fe (i.e., unchelated ferrous iron) that is produced by photoreductive dissociation of the ferric EDTA complex. Prediction by chemostat theory modified to account for the light-mediated formation of bi... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577676 Fri, 30 Dec 2011 05:00:00 +0100 5577676 http://www.medworm.com/index.php?rid=5577675&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210213%26dopt%3DAbstract Authors: Abarca-Grau AM, Burbank LP, De Paz HD, Crespo-Rivas JC, Marco-Noales E, López MM, Vinardell JM, Von Bodman SB, Penyalver R Abstract Rhizobium rhizogenes strain K84 is a commercial biocontrol agent used worldwide to control crown gall disease. The organism binds tightly to polypropylene substrate and efficiently colonizes root surfaces as complex, multilayered biofilms. A genetic screen identified two mutants in which these surface interactions were affected. One of these mutants failed to attach and form biofilms on the abiotic surface; although, interestingly, it exhibited normal biofilm formation on the biological root tip surface. This mutant is disrupted in a wcbD ortholog gene, which is part of a large locus predicted to encode functions for the biosynthesis and expo... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577675 Fri, 30 Dec 2011 05:00:00 +0100 5577675 http://www.medworm.com/index.php?rid=5577674&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210214%26dopt%3DAbstract Authors: Lee J, Jang YS, Choi SJ, Im JA, Song H, Cho JH, Seung DY, Papoutsakis ET, Bennett GN, Lee SY Abstract Clostridium acetobutylicum naturally produces acetone as well as butanol and ethanol. Since acetone cannot be used as a biofuel, its production needs to be minimized or suppressed by cell or bioreactor engineering. Thus, there have been attempts to disrupt or inactivate the acetone formation pathway. Here we present another approach, namely converting acetone to isopropanol by metabolic engineering. Since isopropanol can be used as a fuel additive, the mixture of isopropanol, butanol, and ethanol (IBE) produced by engineered C. acetobutylicum can be directly used as a biofuel. IBE production is achieved by the expression of a primary/secondary alcohol dehydrogenase gene (s... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577674 Fri, 30 Dec 2011 05:00:00 +0100 5577674 http://www.medworm.com/index.php?rid=5577673&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210215%26dopt%3DAbstract In this study we describe a novel detection strategy which uses silver nanorod array-surface-enhanced Raman spectroscopy (NA-SERS) for direct detection of avian mycoplasmas. As proof-of-concept for use in avian diagnostics, we used NA-SERS to detect and differentiate multiple strains of avian mycoplasma species, including Acholeplasma laidlawii, Mycoplasma gallinarum, Mycoplasma gallinaceum, Mycoplasma synoviae, and M. gallisepticum, including vaccine strains 6/85, F, and ts-11. Chemometric multivariate analysis of spectral data was used to classify these species rapidly and accurately with >93% sensitivity and specificity. Furthermore, NA-SERS had a lower limit of detection 100-fold greater than standard PCR and comparable to real-time quantitative PCR. Detection of M. gallisepticum in... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577673 Fri, 30 Dec 2011 05:00:00 +0100 5577673 http://www.medworm.com/index.php?rid=5577672&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210216%26dopt%3DAbstract Authors: Jackson SA, Kotewicz ML, Patel IR, Lacher DW, Gangiredla J, Elkins CA Abstract Two technologies, involving DNA microarray and optical mapping, were used to quickly assess gene content and genomic architecture of recent emergent Escherichia coli O104:H4 and related strains. In real-time outbreak investigations, these technologies can provide congruent perspectives on strain, serotype, and pathotype relationships. Our data demonstrated clear discrimination between clinically, temporally, and geographically distinct O104:H4 isolates and rapid characterization of strain differences. PMID: 22210216 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577672 Fri, 30 Dec 2011 05:00:00 +0100 5577672 http://www.medworm.com/index.php?rid=5577671&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210217%26dopt%3DAbstract Authors: Macdonald J, Master ER Abstract The abundances of nine transcripts predicted to encode lignocellulose-modifying enzymes were measured over the course of Phanerochaete carnosa cultivation on four wood species. Profiles were consistent with sequential decay; transcripts encoding lignin-degrading peroxidases featured significant substrate-dependent response. Chitin synthase was identified as the optimal internal reference gene for transcript quantification. PMID: 22210217 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577671 Fri, 30 Dec 2011 05:00:00 +0100 5577671 http://www.medworm.com/index.php?rid=5577670&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210218%26dopt%3DAbstract Authors: Dimkpa CO, Zeng J, McLean JE, Britt DW, Zhan J, Anderson AJ Abstract The beneficial bacterium Pseudomonas chlororaphis O6 (PcO6) produces indole-3-acetic acid (IAA), a plant growth regulator. However, the pathway involved in IAA production in this bacterium has not been reported. In this paper we describe the involvement of the indole-3-acetamide (IAM) pathway in IAA production in PcO6 and the effects of CuO and ZnO nanoparticles (NPs). Sublethal levels of CuO and ZnO NPs differentially affected the levels of IAA secreted in medium containing tryptophan as the precursor. After 15 h growth, CuO NP-exposed cells had metabolized more tryptophan than the control and ZnO NP-challenged cells. The CuO NP-treated cells produced higher IAA levels than control cultures lacking NPs. ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577670 Fri, 30 Dec 2011 05:00:00 +0100 5577670 http://www.medworm.com/index.php?rid=5577669&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210219%26dopt%3DAbstract This report suggests that the markerless mutagenesis strategy could serve as a model for functional studies of other genes of interest from A. ferrooxidans and multiple mutations could be made in a single A. ferrooxidans strain. PMID: 22210219 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577669 Fri, 30 Dec 2011 05:00:00 +0100 5577669 http://www.medworm.com/index.php?rid=5577668&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210220%26dopt%3DAbstract Authors: Hughes GL, Vega-Rodriguez J, Xue P, Rasgon JL Abstract Wolbachia, a common bacterial endosymbiont of insects, has been shown to protect its hosts against a wide range of pathogens. However, not all strains exert a protective phenotype on their host. Here we assess the affect of two divergent Wolbachia strains, wAlbB from Aedes albopticus and wMelPop from Drosophila melanogaster, on the vector competence of Anopheles gambiae challenged with Plasmodium berghei. We show the wAlbB strain significantly increases P. berghei oocyst levels in the mosquito midgut, while wMelPop modestly suppresses oocyst levels. The wAlbB strain is avirulent to mosquitoes while wMelPop is moderately virulent to mosquitoes pre-bloodmeal, and highly virulent after mosquitoes fed on mice. These varyin... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577668 Fri, 30 Dec 2011 05:00:00 +0100 5577668 http://www.medworm.com/index.php?rid=5577667&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210221%26dopt%3DAbstract Authors: Tosukhowong A, Zendo T, Visessanguan W, Roytrakul S, Pumpuang L, Jaresitthikunchai J, Sonomoto K Abstract Lactococcus garvieae BCC 43578 produces a novel class II bacteriocin, garvieacin Q (GarQ) of 70 amino acids containing a 20 amino acids N-terminal leader peptide, which is cleaved at Gly-Gly site to generate the mature GarQ (5,339 Da), especially inhibitory against Listeria monocytogenes ATCC 19115 and other L. garvieae strains. PMID: 22210221 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577667 Fri, 30 Dec 2011 05:00:00 +0100 5577667 http://www.medworm.com/index.php?rid=5577666&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210222%26dopt%3DAbstract In this study, using a P. eryngii sporeless strain, we constructed a genetic linkage map to introduce a molecular breeding program like marker-assisted selection. Based on the segregation of 294 amplified fragment length polymorphism markers, two mating type factors, and the sporeless trait, the linkage map consisted of 11 linkage groups with a total length of 837.2 cM. The gene region responsible for the sporeless trait was located in linkage group IX with 32 amplified fragment length polymorphism markers and B mating type factor. We also identified eight markers closely linked (within 1.2 cM) to the sporeless locus using bulked segregant analysis-based amplified fragment length polymorphism. One such amplified fragment length polymorphism marker was converted into two sequence tagged sit... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577666 Fri, 30 Dec 2011 05:00:00 +0100 5577666 http://www.medworm.com/index.php?rid=5577665&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22210223%26dopt%3DAbstract Authors: Dodge AG, Wackett LP, Sadowsky MJ Abstract Rhodococcus sp. strain Mel was isolated from soil by enrichment and grew in minimal medium with melamine as the sole N source with a doubling time of 3.5 h. Stoichiometry studies showed that all six nitrogen atoms of melamine were assimilated. The genome was sequenced by Roche 454 pyrosequencing to 13X coverage and a 22.3 kb DNA region was found to contain a homolog to the melamine deaminase gene trzA. Mutagenesis studies showed that the cyanuric acid hydrolase and biuret hydrolase genes were clustered together on a different 17.9 kb contig. Curing and gene transfer studies indicated that 4 of 6 genes required for the complete degradation of melamine were located on a ∼265 kb self-transmissible linear plasmid (pMel2), but this p... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5577665 Fri, 30 Dec 2011 05:00:00 +0100 5577665 http://www.medworm.com/index.php?rid=5547868&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22194284%26dopt%3DAbstract Authors: Ernebjerg M, Kishony R Abstract Our understanding of microbial ecology has been significantly furthered in recent years by advances in sequencing techniques, but comprehensive surveys of the phenotypic characteristics of environmental bacteria remain rare. Such phenotypic data are crucial for understanding the microbial strategies for growth and the diversity of microbial ecosystems. Here, we describe a high-throughput measurement of the growth of thousands of bacterial colonies using an array of flatbed scanners coupled with automated image analysis, and use this system to investigate the growth properties of members of a microbial community from untreated soil. The system provides high-quality measurements of the number of colony forming units, colony growth-rates, and a... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5547868 Thu, 22 Dec 2011 05:00:00 +0100 5547868 http://www.medworm.com/index.php?rid=5547867&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22194285%26dopt%3DAbstract Authors: Nguyen UT, Wenderska IB, Chong MA, Koteva K, Wright GD, Burrows LL Abstract Listeria monocytogenes is an important food-borne pathogen whose ability to form disinfectant tolerant biofilms on a variety of surfaces presents a food safety challenge for manufacturers of ready-to-eat products. Here we developed a high-throughput biofilm assay for L. monocytogenes and as a proof of principle, used it to screen a 80-compound protein kinase inhibitor library to identify molecules that perturb biofilm development. The screen yielded molecules toxic to multiple strains of Listeria at micromolar concentrations, as well as molecules that decreased (≤50% of vehicle control) or increased (≥200%) biofilm formation in a dose-dependent manner without affecting planktonic cell density. ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5547867 Thu, 22 Dec 2011 05:00:00 +0100 5547867 http://www.medworm.com/index.php?rid=5547866&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22194286%26dopt%3DAbstract Authors: You C, Zhang XZ, Zhang YH Abstract We developed a general restriction enzyme-free and ligase-free method for subcloning up to three DNA fragments into any location of a plasmid. The DNA multimer generated by prolonged overlap extension PCR was directly transformed in Escherichia coli [e.g., TOP10, DH5α, JM109, BL21(DE3)] and Bacillus subtilis for obtaining chimeric plasmids. PMID: 22194286 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5547866 Thu, 22 Dec 2011 05:00:00 +0100 5547866 http://www.medworm.com/index.php?rid=5547865&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22194287%26dopt%3DAbstract This study employs multi-locus sequence analysis of environmentally-mediated genes (genes influenced by environmental factors, MLSA-E) to investigate X. fastidiosa relationships and differentiate isolates with low genetic variability. Potential environmentally-mediated genes, including host colonization and survival genes related to infection establishment, were identified a priori. dN/dS (non-synonymous/synonymous substitution rates) were calculated to select genes that may be under increased positive selection compared to previously studied housekeeping genes. Nine genes were sequenced from 54 X. fastidiosa isolates infecting different host plants across the US. Maximum likelihood (ML) and Bayesian phylogenetic (BP) analyses are in agreement with known X. fastidiosa subspecies clades but... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5547865 Thu, 22 Dec 2011 05:00:00 +0100 5547865 http://www.medworm.com/index.php?rid=5547864&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22194288%26dopt%3DAbstract Authors: Sjöstedt J, Koch-Schmidt P, Pontarp M, Canbäck B, Tunlid A, Lundberg P, Hagström A, Riemann L Abstract A bacterial community may be resistant to environmental disturbances if some of its species show metabolic flexibility and physiological tolerance to the changing conditions. Alternatively, disturbances can change the composition of the community and thereby potentially affect ecosystem processes. The impact of disturbance on the composition of bacterioplankton communities was examined in continuous seawater cultures. Bacterial assemblages from geographically closely connected areas, the Baltic Sea (salinity 7 and high dissolved organic carbon, DOC) and Skagerrak (salinity 28 and low DOC) were exposed to gradual opposing changes in salinity and DOC over a three week pe... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5547864 Thu, 22 Dec 2011 05:00:00 +0100 5547864 http://www.medworm.com/index.php?rid=5547863&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22194289%26dopt%3DAbstract This study of the bacterial communities associated with potential biofuel-producing microalgae addresses a little investigated area of microalgal biofuel research and provides a novel approach to harvest biofuel-producing microalgae by using the novel bacterium strain HW001. PMID: 22194289 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5547863 Thu, 22 Dec 2011 05:00:00 +0100 5547863 http://www.medworm.com/index.php?rid=5547862&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22194290%26dopt%3DAbstract Authors: Cheng J, Ma J, Lin J, Fan ZC, Cronan JE, Wang H Abstract Ralstonia solanacearum, a major phytopathogenic bacterium, causes a bacterial wilt disease in diverse plants. Although fatty acid analyses of R. solanacearum showed that they contain primarily palmitic (C16:0), palmitoleic (C16: 1) and cis-vaccenic (C18: 1) acid, little is known of R. solanacearum fatty acid synthesis. The R. solanacearum GMI1000 genome is unusual in that it contains four genes (fabF1, fabF2, fabF3 and fabF4) annotated as encoding 3-ketoacyl-acyl carrier protein synthase II homologues and one gene (fabB) annotated as encoding 3-ketoacyl-acyl carrier protein synthase I. We have analyzed this puzzling apparent redundancy and found that only one of these genes, fabF1, encoded a long chain 3-ketoacyl-acy... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5547862 Thu, 22 Dec 2011 05:00:00 +0100 5547862 http://www.medworm.com/index.php?rid=5547861&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22194291%26dopt%3DAbstract This study was conducted to evaluate the effect of aerosol generation, methods of sampling, storage conditions and relative humidity on the culturability of the mycobacteriophage D29. The lytic phage D29 can kill Mycobacterium tuberculosis and the phage aerosol can be treated as a potential tool for tuberculosis treatment. The culturability of D29 was tested using a test chamber designed for the bioaerosols research against three spray liquids (deionized water, PBS and normal saline), four collection media (suspension medium (SM), nutrient broth, PBS and deionized water), two sampling systems (the all-glass impinger AGI-30 and the Biosampler) and across a range of humidities (20% - 90%). The effect of storage conditions on the culturability of collected sample was also evaluated for the AG... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5547861 Thu, 22 Dec 2011 05:00:00 +0100 5547861 http://www.medworm.com/index.php?rid=5547860&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22194292%26dopt%3DAbstract Authors: Crombé F, Vanderhaeghen W, Dewulf J, Hermans K, Haesebrouck F, Butaye P Abstract A transmission experiment was performed to evaluate the spread of methicillin-resistant Staphylococcus aureus (MRSA) ST398 in nursery piglets. Reproduction ratios (R(0)) in three experimental groups were found to vary between 3.92 and 52.54, indicating that after introduction, MRSA ST398 will spread easily among weaned piglets, with a tendency to become endemic. PMID: 22194292 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5547860 Thu, 22 Dec 2011 05:00:00 +0100 5547860 http://www.medworm.com/index.php?rid=5547859&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22194293%26dopt%3DAbstract Authors: Wertz JT, Kim E, Breznak JA, Schmidt TM, Rodrigues JL Abstract Previously we reported the cultivation of novel verrucomicrobia, including strain TAV2 (93% 16S rRNA gene identity to its nearest cultivated representative, Opitutus terreae PB90-1) from the gut of the termite Reticulitermes flavipes. To gain better insight into the Verrucomicrobia as a whole and understand the role of verrucomicrobia within the termite gut ecosystem, we analyzed a draft genome and undertook a physiological characterization of TAV2. Strain TAV2 is an autochthonous member of the R. flavipes gut microbiota and groups phylogenetically among diverse Verrucomicrobia from R. flavipes and other termites that are represented by 16S rRNA gene sequences alone. TAV2 is a microaerophile, possessing a high-... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5547859 Thu, 22 Dec 2011 05:00:00 +0100 5547859 http://www.medworm.com/index.php?rid=5547858&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22194294%26dopt%3DAbstract Authors: Sulaiman S, Yamato S, Kanaya E, Kim JJ, Koga Y, Takano K, Kanaya S Abstract The gene encoding a cutinase homolog, LC-cutinase, was cloned from a fosmid library of a leaf-branch compost metagenome by functional screening using tributyrin agar plates. LC-cutinase shows the highest amino acid sequence identity of 59.7% to Thermomonospora curvata lipase. It also shows the 57.4% identity to Thermobifida fusca cutinase. When LC-cutinase without a putative signal peptide was secreted to the periplasm of E. coli cells with the assistance of the pelB leader sequence, more than 50% of the recombinant protein, termed LC-cutinase*, was leaked into the extracellular medium. It was purified and characterized. LC-cutinase* hydrolyzed various fatty acid monoesters with acyl chain lengths ... Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5547858 Thu, 22 Dec 2011 05:00:00 +0100 5547858 http://www.medworm.com/index.php?rid=5547857&cid=s_37539_77_f&fid=37539&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22194295%26dopt%3DAbstract We report here the first engineering effort for E. coli biocatalysts to assimilate cellobiose through phosphorolytic mechanism. Cytoplasmic expression of the Saccharophagus cellobiose phosphorylase was shown to enable E. coli to use cellobiose. Subsequent knockout and complementation studies provided solid evidence that the endogenous LacY was responsible for the transport of cellobiose. PMID: 22194295 [PubMed - as supplied by publisher] (Source: Applied and Environmental Microbiology) Applied and Environmental Microbiology journals http://www.medworm.com/rss/comments.php?id=5547857 Thu, 22 Dec 2011 05:00:00 +0100 5547857