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 'Journal of Basic Microbiology' source. Thu, 18 Mar 2010 16:38:21 +0100 http://www.medworm.com/index.php?rid=3254097&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900240 Streptomyces sp. AM-7161 is a producer of an aromatic polyketide medermycin with strong antibacterial and antitumor activity. It has been inefficient to perform genetic manipulations in this strain, which heavily hinders the genetic analysis of some interesting problems concerning tailoring modifications in medermycin biosynthesis. Here, condition optimizations of sporulation and mycelium growth of this strain as well as protoplast preparation and regeneration were conducted systematically. Based on these results, protoplast transformation system was established, and two types of foreign plasmids (integrative and auto-replicating) were efficiently introduced into this strain. Additionally, a conjugation system to mediate plasmid transfer between Escherichia coli and Streptomyces sp. AM-716... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3254097 Tue, 09 Feb 2010 00:00:00 +0100 3254097 http://www.medworm.com/index.php?rid=3254103&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900237 In vitro effect of salivary gland extract from fed Ixodes ricinus, the competent vector of Lyme borreliosis in Europe, on the growth of Borrelia burgdorferi sensu lato (B. garinii, B. afzelii and B. burgdorferi sensu stricto) was examined in BSK-H medium. Motility rate, concentration of motile spirochetes and their morphology were estimated at intervals of 0, 2, 4, 6 and 8 days using darkfield microscopy. Salivary gland extract derived from I. ricinus stimulated markedly the growth of three genomic species of borreliae. The results confirm a substantial role of salivary glands in the mechanism of pathogen transmission to vertebrate host. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3254103 Mon, 08 Feb 2010 00:00:00 +0100 3254103 http://www.medworm.com/index.php?rid=3254102&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900245 RS[alpha] sequencing is a valuable tool for identification of bacterial strains, and for evaluating the genetic structure of indigenous rhizobial populations. The purpose of this study was to evaluate, qualitatively, the presence or absence of RS[alpha] fragment in peanut-nodulating strains isolated from plants grown at four sites in central Argentina. RS[alpha] fragment was found in only three of 26 indigenous strains, and in one of three inoculant strains analyzed. In contrast to results from studies of other symbiotic nitrogen-fixing bacteria, such as soybean-nodulating strains, no correlation was found between generation time and presence of RS[alpha] sequence. Phylogenetic analysis of the 16S rRNA gene sequence grouped peanut-nodulating strains into two clusters, Bradyrhizobium japoni... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3254102 Mon, 08 Feb 2010 00:00:00 +0100 3254102 http://www.medworm.com/index.php?rid=3254101&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900250 Marinobacter comprises Gram-negative, aerobic, motile, and rod-shaped bacteria within the [gamma]-subclass of the Proteobacteria and is known to be halophilic or halotolerant, heterotrophic neutrophile. Two strains classified as belonging to Marinobacter, named PAD-2 and SeT-1, were isolated from marine sediment. The most closely related species of PAD-2 and SeT-1 are M. alkaliphilus and M. guinea, respectively. The strain PAD-2 exhibited remarkably higher denitrification at concentrations of 0.5 to 1 M NaCl (3-6% w/w) than at other salinities (2 and 3 M NaCl, 12-18% w/w), and optimal denitrification was observed in media with 0.5 M NaCl. The effect of pH on denitrification by strain PAD-2 was also examined, and the optimum denitrification occurred at neutral pH rather than under alkaline ... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3254101 Mon, 08 Feb 2010 00:00:00 +0100 3254101 http://www.medworm.com/index.php?rid=3254100&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900272 This study aims to investigate the combined uses of species richness and diversity as well as to estimate the combinatorial effect of species richness and diversity in order to understand their role and distribution in their habitat. To achieve this objective a study was designed targeting the rhizosphere of Jatropha curcas L. which were planted in various soil conditions on five distinctive sites of Gujarat state (India). These sites were constantly monitored and studied for the species richness and evenness ("heterogeneity"). The isolates were checked for their PGPR potentials like Phosphate solubilisation, Siderophore production, Indole acetic acid production, ACC deaminase production, HCN production, EPS production and Ammonia production. The results obtained were used to calculate ric... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3254100 Mon, 08 Feb 2010 00:00:00 +0100 3254100 http://www.medworm.com/index.php?rid=3254099&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900337 Marine picoplankton of the genus Synechococcus and Prochlorococcus spp. are widely studied members of the picocyanobacterial clade, composed of unicellular cyanobacteria that dominate pelagic regions of the ocean. Less studied are the related freshwater Synechococcus spp. that similarly dominate the euphotic zone of oligotrophic lakes. Previous work has shown that marine picocyanobacteria harbor a small gene, hcp, that encodes a 62 amino acid protein 100% conserved among all strains examined. The gene is restricted exclusively to the picocyanobacterial lineage. The current study reveals that hcp is also 100% conserved in four freshwater Synechococcus spp. strains isolated from the Laurentian Great Lakes, and that the gene constitutively expressed with genes encoding a ribosomal protein and... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3254099 Mon, 08 Feb 2010 00:00:00 +0100 3254099 http://www.medworm.com/index.php?rid=3254098&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900358 A soil bacterium isolated from oil-polluted sand samples collected in the Saudi Arabian Desert has been determined as Nocardia cyriacigeorgica, which has a high capacity of degrading and utilizing a broad range of hydrocarbons. The metabolic pathways of three classes of hydrocarbons were elucidated by identifying metabolites in cell-free extracts analyzed by GC/MS and HPLC/UV-Vis in comparison with standard compounds. During tetradecane oxidation, tetradecanol; tetradecanoic acid; dodecanoic acid; decanoic acid could be found as metabolites, indicating a monoterminal degradation pathway of n -alkanes. The oxidation of pristane resulted in the presence of pristanoic acid; 2-methylglutaric acid; 4,8-dimethylnonanoic acid; and 2,6-dimethylheptanoic acid, which give rise to a possible mono- an... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3254098 Mon, 08 Feb 2010 00:00:00 +0100 3254098 http://www.medworm.com/index.php?rid=3178576&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900239 An aqueous mixture of goethite, quartz, and lead chloride (PbCl2) was treated with the sulfate-reducing bacterium, Desulfovibrio desulfuricans G20 (D. desulfuricans G20), in a medium specifically designed to assess metal toxicity. In the presence of 26 [mu]M of soluble Pb, together with the goethite and quartz, D. desulfuricans G20 grew after a lag time of 5 days compared to 2 days in Pb-, goethite-, and quartz-free treatments. In the absence of goethite and quartz, however, with 26 [mu]M soluble Pb, no measurable growth was observed. Results showed that D. desulfuricans G20 first removed Pb from solutions then growth began resulting in black precipitates of Pb and iron sulfides. Transmission electron microscopic analyses of thin sections of D. desulfuricans G20 treated with 10 [mu]M PbCl2... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178576 Sat, 16 Jan 2010 00:00:00 +0100 3178576 http://www.medworm.com/index.php?rid=3178589&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900171 The enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase cleaves the ethylene precursor ACC into [alpha]-ketobutyrate and ammonia. The decreased level of ethylene allows the plant to be more resistant to a wide environmental stress including plant pathogens. In the present study, we characterized the ACC deaminase activity of a Pseudomonas entomophila strain PS-PJH isolated from the red pepper rhizosphere region of red pepper grown at Jinan, Korea. The isolate produced 23.8 ± 0.4 [mu]mol of [alpha]-ketobutyrate/mg of protein/h during ACC deamination under in vitro conditions. Polymerase chain reaction for acdS gene showed that the isolated P. entomophila strain PS-PJH carry sequences similar to the known acdS genes. Results of the multiple sequence alignment revealed >99% identity (nu... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178589 Fri, 15 Jan 2010 00:00:00 +0100 3178589 http://www.medworm.com/index.php?rid=3178588&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900295 Endophytes include all organisms that during a variable period of their life, colonize the living internal tissues of their hosts without causing detectable symptoms. Several fungal endophytes have been isolated from a variety of plant species which have proved themselves as a rich source of secondary metabolites. The reported natural products from endophytes include antibiotics, immunosuppresants, anticancer compounds, antioxidant agents, etc. For the first time Rosa damacaena (rose) has been explored for its endophytes. The rose oil industry is the major identified deligence for its application in perfumery, flavouring, ointments, and pharmaceuticals including various herbal products. During the present investigation fungal endophytes were isolated from Rosa damacaena. A total of fifty f... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178588 Fri, 15 Jan 2010 00:00:00 +0100 3178588 http://www.medworm.com/index.php?rid=3178587&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800400 The diversity of proteolytic bacteria associated with a glacier and cold environment soils from three different locations in Lahaul and Spiti, India was investigated. Two hundred seventeen bacterial strains were isolated in pure culture. Subsequently these strains were screened for protease-production and one hundred nine showed protease production. From these protease producing psychrotrophic bacteria twenty showing high enzyme production at low temperature and alkaline pH were characterized and identified. The 16S rRNA phylogenetic analysis revealed that none of the strains showed 100% identity with the validly published species of various genera. Isolates belonged to three classes i.e. Actinobacteria, Gammaproteobacteria and Alphaproteobacteria, and were affiliated with the genera Acine... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178587 Fri, 15 Jan 2010 00:00:00 +0100 3178587 http://www.medworm.com/index.php?rid=3178586&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900054 The extracellular endopeptidase synthesized by soil bacterium Pseudomonas fluorescens was purified to homogeneity in a four-step procedure. The enzyme was purified 45-fold, with a 20% recovery. The endopeptidase appeared to be a monomer with a molecular mass of approx. 50 kDa. The enzyme was active in the pH range of 7 to 10. The optimal activity was detected at pH 9.0 and at 42 °C.Enzyme activity was inhibited by EDTA, EGTA and 1,10 phenanthroline, typical metalloprotease inhibitors. Ca2+ activated the enzyme while Zn2+, Co2+, Cd2+(in high concentration) strongly inhibited it. The presence of calcium ions strongly stabilized the enzyme with regard to thermal resistance. The amino acid sequence of fragments of the enzymatic protein determined by MS analysis revealed a high similarity to t... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178586 Fri, 15 Jan 2010 00:00:00 +0100 3178586 http://www.medworm.com/index.php?rid=3178585&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900113 A homologue of the adenylyl cyclase (AC) gene of Neurospora crassa, named Fpacy1 was cloned from the genomic library of Fusarium proliferatum ITEM 2287 by screening the library with a DNA fragment amplified by using PCR primers designed from conserved sequences of the catalytic domain of AC genes from other fungi. The deduced FPACY1 protein had 53-77% identity with the AC proteins of other fungi. [Delta]Fpacy1 mutants obtained by targeted gene disruption showed retarded vegetative growth, increased conidiation and delayed conidial germination. Colonization capability of the mutants, assessed on maize seedlings and tomato fruits also was adversely affected. In sexual crosses the AC mutants retained full male fertility, but their female fertility decreased significantly. Disruption of Fpacy1... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178585 Fri, 15 Jan 2010 00:00:00 +0100 3178585 http://www.medworm.com/index.php?rid=3178584&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900122 The objective of this work was to determine the effects of different carbon and nitrogen sources on the growth and bacteriocin production of this microorganism. A fractional factorial design 35-1 was applied to evaluate the effects of five nutrients (glucose, lactose, yeast extract, tryptone and meat peptone), at three different concentrations (0, 1 and 2%). Results were statistically analyzed for linear and quadratic effects of nutrients, along with their interactions. All the nutrients tested stimulated the cell growth and bacteriocin production, but lactose had not a significant influence on the last response. The linear effects of higher magnitude on biomass and bacteriocin production were those of yeast extract and tryptone. The results demonstrated that there were significant interac... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178584 Fri, 15 Jan 2010 00:00:00 +0100 3178584 http://www.medworm.com/index.php?rid=3178583&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900133 A gene encoding an organic solvent-stable protease was amplified from Pseudomonas aeruginosa strain K by polymerase chain reaction using consensus primers based on multiple sequence alignment of alkaline and metalloprotease genes from Pseudomonas species. The gene, which consisted of 1440 bp nucleotides and deduced 479 amino acid residues, was successfully expressed in pGEX-4T-1 expression system in the presence of 1.0 mM IPTG, after an incubation of 6 h at 37 °C. Under these conditions, the recombinant strain K protease was, subsequently, released into the periplasm of E. coli BL21 (DE3) with an optimum proteolytic activity detected at 1.0112 U/ml. To date, this is the first reported expression of alkaline protease (aprA) with such remarkable property in Escherichia coli. (© 2010 WILEY-... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178583 Fri, 15 Jan 2010 00:00:00 +0100 3178583 http://www.medworm.com/index.php?rid=3178582&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900138 In this study, the P(3HB) biosynthesis operon carrying the phbCPs P(3HB) synthase was successfully cloned and sequenced using a homologous probe. Three open reading frames encoding NADPH-dependent acetoacetyl-coenzyme A reductase (PhbBPs), [beta]-ketothiolase (PhbAPs) and P(3HB) synthase (PhbCPs) were found in the phb operon. The genetic organization of phb operon showed a putative promoter region, followed by phbBPs-phbAPs-phbCPs. phbRPswhich encoded a putative transcriptional activator was located in the opposite orientation, upstream of phbBACPs. Heterologous expression of pGEM[Prime]ABex harboring phbCPs in Escherichia coli JM109 resulted in P(3HB) accumulation of up to 40% of dry cell weight (DCW). (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbio... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178582 Fri, 15 Jan 2010 00:00:00 +0100 3178582 http://www.medworm.com/index.php?rid=3178581&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900155 In this study, we found that a newly isolated non-laccase-producing fungus, Gongronella sp. W5, could induce overproduction of laccase in Panus rudis. The enzyme activity, 148,200 U l-1, was 25 times higher than the activity obtained from a chemical induction using copper/o -toluidine as inducers. A new laccase isozyme from the interaction of P. rudis and G. W5 was purified and characterized. A further test showed that some pH resistant metabolites secreted by G. W5 acted as signals to induce P. rudis laccase. Laccase is also highly expressed by Trametes sp. AH28-2 in interaction with Trichoderma sp. ZH1. However, no laccase activity was observed from the cross-over interactions of P. rudis -Trichoderma sp. ZH1 or Trametes sp. AH28-2-G. W5. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhe... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178581 Fri, 15 Jan 2010 00:00:00 +0100 3178581 http://www.medworm.com/index.php?rid=3178580&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900162 Under the current assay conditions, lipase production in mineral medium was only detected in the presence of vegetable oils, reaching the highest specific activity with olive oil. In this way, effect of different environmental conditions on fungal morphology and olive oil-induced extracellular lipases production from Aspergillus niger MYA 135 was studied. It was observed that addition of 1.0 g l-1 FeCl3to the medium encouraged filamentous growth and increased the specific activity 6.6 fold after 4 days of incubation compared to the control. However, major novelty of this study was the satisfactory production of an acidic lipase at initial pH 3 of the culture medium (1.74 ± 0.06 mU [mu]g-1), since its potencial applications in food and pharmaceutical industry are highly promising. (© 2010... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178580 Fri, 15 Jan 2010 00:00:00 +0100 3178580 http://www.medworm.com/index.php?rid=3178579&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900178 Growth of Pseudomonas aeruginosa on acyclic terpene alcohols such as geraniol depends on the presence of the atuRABCDEFGH gene cluster and a functional acyclic terpene utilisation (Atu) pathway. The proteins encoded by the atu gene cluster are necessary but not sufficient for growth on acyclic terpenes. Comparative 2-dimensional polyacrylamide gel electrophoresis of soluble P. aeruginosa proteins revealed the presence of an additional spot (besides Atu proteins) that is specifically expressed in geraniol cells but is absent in isovalerate-grown cells. The spot was identified as PA1982 gene product a pyrroloquinoline quinone (PQQ) dependent ethanol oxidoreductase (QEDH). Inactivation of PA1982 by insertion mutagenesis resulted in inability of the mutant to utilise ethanol and in reduced gro... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178579 Fri, 15 Jan 2010 00:00:00 +0100 3178579 http://www.medworm.com/index.php?rid=3178578&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900203 Laccase production by solid state fermentation (SSF) using an indigenously isolated litter dwelling fungus Fusarium incarnatum LD-3 was optimized. Fourteen medium components were screened by the initial screening method of Plackett-Burman. Each of the components was screened on the basis of 'p' (probability value) which was above 95% confidence level. Ortho-dianisidine, thiamine HCl and CuSO4 · 5 H2O were identified as significant components for laccase production. The Central Composite Design response surface methodology was then applied to further optimize the laccase production. The optimal concentration of these three medium components for higher laccase production were (g/l): CuSO4 · 5 H2O, 0.01; thiamine HCl, 0.0136 and ortho-dianisidine, 0.388 mM served as an inducer. Wheat straw,... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178578 Fri, 15 Jan 2010 00:00:00 +0100 3178578 http://www.medworm.com/index.php?rid=3178577&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900227 In the course of study of epiphytic microorganisms occurring on the surface of roots of Taxus baccata L. a new strain Streptomyces sp. AC113 was isolated. According to 16S ribosomal DNA-based identification the new strain is 99% identical with Streptomyces flavidofuscus. This strain cultivated in an arginine glycerol medium produced three major metabolites identified as (-)-8-O -methyltetrangomycin (1), 8-O -methyltetrangulol (2) and 8-O -methyl-7-deoxo-7-hydroxytetrangomycin (3). The chemical structures of these angucyclines were elucidated by 1D and 2D NMR as well as by mass spectrometry. Isolated angucycline metabolites showed significant antimicrobial activity against Bacillus cereus and Listeria mocytogenes. Cytotoxic activities of compounds 1, 2 and 3 against four cell lines (B16, HT... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=3178577 Fri, 15 Jan 2010 00:00:00 +0100 3178577 http://www.medworm.com/index.php?rid=2868657&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900037 The objective of this study was to achieve a simple and rapid technique for the double staining of bacterial SOD and catalase on the same polyacrylamide gel. SOD detection was carried out using nitro-blue tetrazolium (NBT) dye reduction followed by ferricyanide precipitation for negative staining of the catalase enzyme on the same gel. The staining procedure resulted in pale blue SOD bands while catalase appeared as yellow bands against a greenish blue background on the same gel. This technique was used to detect changes in the polymorphic forms of these enzymes in Deinococcus radiodurans R1 and Kocuria sp. C2 subjected to stresses like UV and gamma radiation and desiccation. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868657 Tue, 06 Oct 2009 23:00:00 +0100 2868657 http://www.medworm.com/index.php?rid=2868671&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900035 This study found that 2-dodecanol is able to inhibit hyphal development and block SIR2 up-regulation, even in hyphal-inducing growth conditions. We suggest that SIR2 may be involved in Candida albicans quorum-sensing and serum-induced yeast-hyphae transition via the Ras1-cAMP-Efg1 signalling cascade. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868671 Mon, 05 Oct 2009 23:00:00 +0100 2868671 http://www.medworm.com/index.php?rid=2868670&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900066 ESBL-producing E. coli isolates have been isolated from eight of seventy seven faecal samples (10.4%) of wild boars in Portugal. The ESBL types identified by PCR and sequencing were blaCTX-M-1 (6 isolates) and blaCTX-M-1 + blaTEM1-b (2 isolates). Further resistance genes detected included tet (A) or tet (B) (in three tetracycline-resistant isolates), aad A (in three streptomycin-resistant isolates), cml A (in one chloramphenicol-resistant isolate), sul 1 and/or sul 2 and/or sul 3 (in all sulfonamide-resistant isolates). The intI 1 gene encoding class 1 integrase was detected in all ESBL-producing E. coli isolates. One isolate also carried the intI 2 gene, encoding class 2 integrase. The ESBL-producing E. coli isolates could be assigned to phylogenetic groups B1 (3 isolates), B2 (3 isolates... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868670 Mon, 05 Oct 2009 23:00:00 +0100 2868670 http://www.medworm.com/index.php?rid=2868669&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900137 A mutant strain of the curdlan-producing bacterium Agrobacterium sp. ATCC 31749, isolated by ethylmethane sulfonate mutagenesis and resistance to ampicillin, was capable of elevated curdlan synthesis. Using 2.5% corn syrup, glucose or maltose as a carbon source, the mutant strain was shown to produce a 1.5-fold, 1.5-fold or 1.5-fold higher level of curdlan, respectively, than its parent strain after 120 h of growth. The mutant strain produced higher curdlan levels after 96 or 120 h of growth on glucose or maltose as a carbon source than it did on corn syrup. Biomass production by the mutant strain grown on the carbon sources studied was slightly elevated compared to its parent strain. It was concluded that the elevated curdlan production observed for the mutant strain grown on corn syrup o... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868669 Mon, 05 Oct 2009 23:00:00 +0100 2868669 http://www.medworm.com/index.php?rid=2868668&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900170 This paper deals with the interactions of chromium (Cr) with biological systems, focusing in particular on yeasts and fungi. These interactions are analysed with primarily regard to biochemical functions, but higher levels of organization are also considered. Thus, the morphological and cytological characteristics of selected microorganisms in response to exposure to chromium ions are evaluated. The different oxidation states of chromium and reactive oxygen species (ROS) generated in redox reactions with chromium ions are presented and characterized. The interactions of the most exposed subcellular structures, including the cell wall, plasma membrane and nuclei, have been deeply investigated in recent years, for two major reasons. The first is the toxicity of chromium ions and their strong... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868668 Mon, 05 Oct 2009 23:00:00 +0100 2868668 http://www.medworm.com/index.php?rid=2868667&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800381 Bitto of Valchiavenna, an artisanal Italian cheese produced without the addition of any starter cultures, has been attributed a protected designation origin (PDO) cheese, but the strain composition of the natural microbial population colonizing this traditional dairy product is still unknown. To obtain preliminary information on the non starter lactic acid bacteria involved in its ripening, a total of 136 NSLAB isolates, randomly selected from MRS and M17 agar plates, were collected from three different cheese samples after 120 days of ripening. The new isolates were identified by combining PCR 16S-23S rDNA spacer analyses, partial 16S rRNA gene sequencing, species-specific probes and colony hybridization. Eighty-two isolates, representing 60% of the total strains selected, were homofermen... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868667 Mon, 05 Oct 2009 23:00:00 +0100 2868667 http://www.medworm.com/index.php?rid=2868666&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800393 Co-production of [gamma] -glutamylcysteine ([gamma] -GC) and glutathione (GSH) by a novel mutant strain Saccharomyces cerevisiae FC-3 and its kinetic analysis were investigated. The strain could produce [gamma] -GC and GSH with high yields (4.22 and 14.3 mg/g-DCW, respectively) in batch submerged cultures. Effects of medium components and cultivation conditions on cell growth and the contents of intracellular [gamma] -GC and GSH were examined. Results show that 2% (w/v) sucrose and 2.5% (w/v) yeast extract are the best carbon and nitrogen sources, respectively, and supplement of three amino acids (glycine, cysteine and glutamate), each at 0.08% (w/v), in the medium could enhance [gamma] -GC and GSH production. In addition, optimal operating conditions are at the initial pH value of 7.0, 30... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868666 Mon, 05 Oct 2009 23:00:00 +0100 2868666 http://www.medworm.com/index.php?rid=2868665&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800364 This study is expected to greatly facilitate the use of the RNAi technology for the anti-HCMV studies. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868665 Mon, 05 Oct 2009 23:00:00 +0100 2868665 http://www.medworm.com/index.php?rid=2868664&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900068 Many fungi are capable of secreting the wide spectrum of hydrolytic enzymes. We characterized an inducible proteinase secretion in yeasts, Saccharomyces cerevisiae. The proteinase secretion by S. cerevisiae was induced in the presence of yeast extract, or of purified proteins, such as bovine serum albumin, casein, or ovalbumin, and some proteolytic activity was present also without protein inducer. We found that properties of proteinases induced under cultivation conditions were different in various aspects (temperature- and pH-dependencies, substrate specificities, sensitivities to proteinase inhibitors). Proteinase activities were also characterized by gelatin zymography. Multiple proteinase bands with wide-molecular weights (ranging from 45 to 240 kDa) were detected and patterns of prot... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868664 Mon, 05 Oct 2009 23:00:00 +0100 2868664 http://www.medworm.com/index.php?rid=2868663&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900084 An extremely acidic mine drainage (AMD) water sample was collected in 1998 and 2008 from Panandhro lignite mine, Gujarat, India. The yeast isolated from this sample was identified using mini API identification system, as a member of genus Candida. The major cellular fatty acids detected by FAME from the isolate are C16:0 and C18:2 cis 9,12/C18:0[alpha] as 25.23 and 19.5%, respectively. The isolate was identified as Candida digboiensis by 18S rRNA gene sequence analysis and designated as Candida digboiensis SRDyeast1. Phylogenetic analysis using D1/D2 variable domains showed that the closest relative of this strain is Candida blankii with 3% divergence. This organism has been reported for the first time from the lignite mine AMD sample, and for cellular fatty acid analysis. This yeast is ab... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868663 Mon, 05 Oct 2009 23:00:00 +0100 2868663 http://www.medworm.com/index.php?rid=2868662&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900085 This study demonstrates the presence of a wide array of critical virulence factors in diverse strains of Vibrio cholerae non-O1/non-O139. Hence, this serogroup can no longer be ignored as an environmental reservoir of virulence genes. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868662 Mon, 05 Oct 2009 23:00:00 +0100 2868662 http://www.medworm.com/index.php?rid=2868661&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900089 The yeast strain CLOA 72 isolated from the effluent of a dairy industry in Brazil and identified as Trichosporon montevideense, was able to grow and produce a glycolipid biosurfactant when cultured on a mineral medium (MM) with sunflower oil as the carbon source. Biosurfactant production was partially growth-associated and maximal emulsification activity was observed at 144 h of cultivation (78.92%). The biosurfactant purified by precipitation with ethanol showed 78.66% emulsifying activity when used in concentrations above 4.5 mg/ml and was able to reduce the surface tension of water to values below 44.9 mN/m. The critical micellar concentration (CMC) was found to be 2.2 mg/ml. The highest emulsifying activity (E24) has been observed with vegetable oils, toluene, kerosene, isooctane, cycl... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868661 Mon, 05 Oct 2009 23:00:00 +0100 2868661 http://www.medworm.com/index.php?rid=2868660&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900095 We determined the presence of class 1 integrons related to the acquisition of resistance to antimicrobials in Aeromonas spp. isolated from individuals with diarrhea. Species were identified as A. caviae, A. hydrophila, A. veronii and A. media using PCR-RFLP of the 16S rDNA. Selected isolates were further characterized by ERIC-PCR. Resistance to chloramphenicol, aztreonam, tetracycline, trimethoprim/sulfamethoxazole, nalidixic acid and streptomycin, among others, was determined using the Kirby-Bauer method. Integrons were detected by PCR amplification of the 5[prime] conserved, variable, and 3[prime] conserved regions. Sequencing of the variable regions revealed class 1 integrons with cassettes encoding resistance to trimethoprim (dfrA12, dfrA15, dfrB4), streptomycin/spectinomycin (aadA2, a... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868660 Mon, 05 Oct 2009 23:00:00 +0100 2868660 http://www.medworm.com/index.php?rid=2868659&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200900124 From stool specimens of 118 healthy children's (1-14 years) in Portugal 92 E. coli and 101 Enterococcu s spp. strains have been isolated. Almost half (40.2%) of the E. coli isolates were resistant to ampicillin, 25.0% were resistant to tetracycline and 26.1% were resistant to streptomycin. Resistance genes detected by specific PCR included blaTEM and/or blaSHV and/or blaCTX-M (33 of 37 ampicillin and/or cefotaxime resistant isolates), tet (A) and/or tet (B) (16 of 23 tetracycline-resistant isolates), aad A (19 of 24 streptomycin-resistant isolates), cml A (in the two chloramphenicol-resistant isolates), aac (3)-II with/without aac (3)-IV (in the four gentamicin-resistant isolates), sul 1 and/or sul 2 and/or sul 3 (in all trimethoprim/sulfamethoxazole resistant isolates). The majority of th... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868659 Mon, 05 Oct 2009 23:00:00 +0100 2868659 http://www.medworm.com/index.php?rid=2868658&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800174 Infections with Mollicutes species (such as Mycoplasma, Acholeplasma, and Ureaplasma) can induce a variety of problems in living organisms and laboratory cell cultures. Therefore, it is necessary to establish a routine diagnostic protocol for Mycoplasma infection in order to ensure reliable research results, as well as the safety of commercial biological products. For that purpose a novel PCR-based procedure using specific designed primers complementary to 16S rRNA genome region of mollicute species was evaluated. PCR was optimized and sensitivity and specificity was evaluated by defined cell count concentrations (2-31250 CFU/ml) of different strains of Mycoplasma, Acholeplasma and Ureaplasma. Amplicon (272 bp) was cloned by PCR-cloning and sequenced by dideoxy chain termination. PCR, was ... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2868658 Mon, 05 Oct 2009 23:00:00 +0100 2868658 http://www.medworm.com/index.php?rid=2851195&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800282 Out of 15 Penicillium species screened for lectin activities, P. griseofulvum and P. thomii were found to possess mycelial lectin activity. None of the species displayed extracellular or cell surface-bound lectin activity. Both species agglutinated rabbit erythrocytes. P. griseofulvum lectin showed specificity to human type O erythrocytes. While P. thomii lectin specifically agglutinated human type A erythrocytes. Highest lectin activities from P. thomii and P. griseofulvum were expressed after 8 and 7 days of growth, respectively. Lectins from both the species displayed a high binding affinity to chondroitin-6-sulphate, mucin, asialofetuin, D-sucrose, and D-trehalose. Ammonium sulphate at 50% saturation yielded 80% of the total lectin activity. Dialysis and ultrafiltration of the precipit... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2851195 Wed, 30 Sep 2009 23:00:00 +0100 2851195 http://www.medworm.com/index.php?rid=2851194&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800328 Endophytes are microorganisms that colonize plant tissues internally without causing harm to the host. Despite the increasing number of studies on sweet orange pathogens and endophytes, yeast has not been described as a sweet orange endophyte. In the present study, endophytic yeasts were isolated from sweet orange plants and identified by sequencing of internal transcribed spacer (ITS) rRNA. Plants sampled from four different sites in the state of São Paulo, Brazil exhibited different levels of CVC (citrus variegated chlorosis) development. Three citrus endophytic yeasts (CEYs), chosen as representative examples of the isolates observed, were identified as Rhodotorula mucilaginosa, Pichia guilliermondii and Cryptococcus flavescens. These strains were inoculated into axenic Citrus sinensis... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2851194 Wed, 30 Sep 2009 23:00:00 +0100 2851194 http://www.medworm.com/index.php?rid=2851192&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200990015 No Abstract (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2851192 Wed, 30 Sep 2009 23:00:00 +0100 2851192 http://www.medworm.com/index.php?rid=2851191&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200990014 Scanning electron micrographs of endophytic yeast cells of the species Cryptococcus flavescens colonizing citrus plants after inoculation. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2851191 Wed, 30 Sep 2009 23:00:00 +0100 2851191 http://www.medworm.com/index.php?rid=2427321&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800310 Characterization of bovine viral diarrhea virus (BVDV) isolates has been focused of several studies this last decade. Until now lots of new strains are being unfolded maybe due to the viral fast mutation ability. As we focused our research on water buffalo immunology, we were able to identify a probable new BVDV isolates. RNA was extracted from water buffalo blood in the Philippines. The extracted RNA was reverse-transcribed and synthesized cDNA. Oligonucleotide primers from the viral E2 region were used to amplify the target viral gene and later purified, cloned and sequenced. The E2 region with 420 bp nucleotides long was compared with existing published sequences in the GenBank. Based on the constructed phylogenetic tree, the isolated strain showed to be a BVDV type 1b along with Osloss... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2427321 Tue, 19 May 2009 04:00:00 +0100 2427321 http://www.medworm.com/index.php?rid=2427320&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800227 Endoglucanase (EG) from A. terreus DSM 826 grown on sugar cane bagasse as a carbon source was purified using acetone fractionation, then a Sepharose-4B chromatographic column, with purification of about 27-fold and 10.5% recovery. The optimum temperature and pH for activity of the purified EG were found to be 50 °C and pH 4.8, respectively. The purified enzyme can stand heating up to 50 °C for 1 h without apparent loss of activity. However, the enzyme, incubated at 80 °C for 5 min, showed about 56% loss of activity. Optimum EG activity was recorded with a citrate buffer system (pH 4.8; 0.05 M). Co2+ (2.5 × 10-2 M) and Zn2+ (5 × 10-2 M) were found to activate the purified EG of A. terreus DSM 826 by about 83 and 25%, respectively. On the other hand, Hg2+ inhibited the activity of the p... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2427320 Tue, 19 May 2009 04:00:00 +0100 2427320 http://www.medworm.com/index.php?rid=2427319&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800229 An extracellular lipase from Pseudomonas aeruginosa ATCC 27853 has been purified and its enzymatic characteristics were determined. According to SDS-PAGE and gel filtration molecular mass estimated to be 30 kDa, what classified the lipase in group I.1. Although 14 lipases from P. aeruginosa with similar molecular mass are referred to date, their basic enzymatic properties have not been reported yet. To address the gap we found: the optimal temperature and pH in water solution being 50 °C and 9.3, respectively; the lipase was inhibited with Hg2+ ions and sodium dodecylsulphate (SDS), while non-ionic detergent Triton X-100 activated the enzyme; the lipase hydrolyzed more rapidly middle chain triglycerides and it was not regiospecific; the lipase demonstrated naturally occurring stability in... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2427319 Tue, 19 May 2009 04:00:00 +0100 2427319 http://www.medworm.com/index.php?rid=2427318&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800250 We examined biofilm formation and first attachment maintance of biofilms of Pseudomonas spp., Pseudomonas aeruginosa, Aeromonas spp, sulphate reducing bacteria and filamentous fungi. A simulated recirculating cooling-water system was used. Heterotrophic bacteria counts on galvanized steel and glass surfaces rose during the tidy period of 720 hours. In addition, we determined that although Pseudomonas spp., Pseudomonas aeruginosa and Aeromonas spp. were the pioneer colonizers, they surprisingly could not be determined in the biofilms on both types of surface after 456 hours. Sulphate reducing bacteria were observed in biofilms on both surfaces from the outset of the experiments. Filamentous fungi were seen on the galvanized steel and glass surfaces after 0.5 h. (© 2009 WILEY-VCH Verlag Gmb... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2427318 Tue, 19 May 2009 04:00:00 +0100 2427318 http://www.medworm.com/index.php?rid=2427317&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800301 In conclusion, the cyanobacterium may survive better in As(V) than As(III) contaminated fields because of its low toxicity and pronounced induction of antioxidative defense system. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2427317 Tue, 19 May 2009 04:00:00 +0100 2427317 http://www.medworm.com/index.php?rid=2427316&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800312 Extensive use of metals in various industrial applications has caused substantial environmental pollution. Molybdenum-reducing bacteria isolated from soils can be used to remove molybdenum from contaminated environments. In this work we have isolated a local bacterium with the capability to reduce soluble molybdate to the insoluble molybdenum blue. We studied several factors that would optimize molybdate reduction. Electron donor sources such as glucose, sucrose, lactose, maltose and fructose (in decreasing efficiency) supported molybdate reduction after 24 h of incubation with optimum glucose concentration for molybdate reduction at 1.5% (w/v). The optimum pH, phosphate and molybdate concentrations, and temperature for molybdate reduction were pH 6.5, 5.0, 25 to 50 mM and 37 °C, respecti... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2427316 Tue, 19 May 2009 04:00:00 +0100 2427316 http://www.medworm.com/index.php?rid=2427315&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800318 Solid-state fermentation was carried out for the production of extra-cellular L-methioninase by Aspergillus flavipes (Bain and Sart.) using nine agro-industrial residues, namely wheat bran, rice bran, wheat flour, coconut seeds, cotton seeds, ground nut cake, lentil hulls, soya beans and chicken feathers. Chicken feathers were selected as solid substrate for L-methioninase production by A. flavipes. The maximum L-methioninase productivity (71.0 U/mg protein) and growth (11 mg protein/ml) of A. flavipes was obtained using alkali pretreated chicken feathers of 50% initial moisture content as substrate supplemented with D-glucose (1.0% w/v) and L-methionine (0.2% w/v). External supplementation of the fermentation medium with various vitamin sources has no overinductive effect on L-methioninas... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2427315 Tue, 19 May 2009 04:00:00 +0100 2427315 http://www.medworm.com/index.php?rid=2427314&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800357 In this study, we identified the putative homolog of the iron-storage protein-encoding gene, dpsL, in the intracellular pathogen Legionella pneumophila and demonstrated its expression under iron-limited conditions and its responses to multiple stresses. Quantitative real-time PCR analysis indicated that the expression of dpsL was enhanced under iron limitation regardless of the growth phase. Compared with the wild-type cells, the cells devoid of dpsL were heat and H2O2-sensitive. In contrast to the dps mutants of other bacteria, the growth of the dpsL mutant in an iron-deprived medium was delayed but finally reached the same cell density as wild-type cells during the stationary phase of growth. The finding that the dpsL mutant is salt resistant suggested the involvement of DpsL in virulenc... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2427314 Tue, 19 May 2009 04:00:00 +0100 2427314 http://www.medworm.com/index.php?rid=2427313&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800359 The phenotypic and genotypic characterization of sixty-two rhizobial isolates obtained from nodules of Arachis hypogaea in north-western Morocco was performed. Their physiological and biochemical properties revealed a great deal of diversity among them. Isolates were classified into two major groups based on the numerical analysis of their phenotypic and genotypic characteristics. Isolates in the first group were alkali- and salt-sensitive, slow or extra-slow growers; they did not use disaccharides as carbon source and varied in the use of amino acids. ARDRA analysis of the 16S rDNA region grouped them together with reference strains belonging to the genus Bradyrhizobium. In the second group, isolates were fast growers, acid-sensitive, and alkali- and salt-tolerant; they used both mono and... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2427313 Tue, 19 May 2009 04:00:00 +0100 2427313 http://www.medworm.com/index.php?rid=2427312&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800372 In order to identify the proteins associated with Helicobacter pylori colonization in mice, we used 2-dimensional gel electrophoresis (2-DE) to analyze the membrane- and soluble-cellular proteins extracted from H. pylori strain 26695 and the mouse-passaged homolog 88-3887. We defined 2- and 3-fold changes in protein expression as the threshold values for differential expression in the membrane-protein and whole-cell-protein fractions, respectively. The differentially expressed proteins were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/TOF). A total of 29 proteins, including 16 membrane- or membrane-associated proteins (13 upregulated, 3 downregulated) and 13 cellular proteins (10 upregulated, 3 downregulated) were differentially expr... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2427312 Tue, 19 May 2009 04:00:00 +0100 2427312 http://www.medworm.com/index.php?rid=2851193&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800359 The phenotypic and genotypic characterization of sixty-two rhizobial isolates obtained from nodules of Arachis hypogaea in north-western Morocco was performed. Their physiological and biochemical properties revealed a great deal of diversity among them. Isolates were classified into two major groups based on the numerical analysis of their phenotypic and genotypic characteristics. Isolates in the first group were alkali- and salt-sensitive, slow or extra-slow growers; they did not use disaccharides as carbon source and varied in the use of amino acids. ARDRA analysis of the 16S rDNA region grouped them together with reference strains belonging to the genus Bradyrhizobium. In the second group, isolates were fast growers, acid-sensitive, and alkali- and salt-tolerant; they used both mono and... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2851193 Mon, 18 May 2009 23:00:00 +0100 2851193 http://www.medworm.com/index.php?rid=2297692&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800345 Degrading hydrocarbon by Streptococcus sp. BT-003 as a kind of microbe for oil recovery was analyzed in this paper. The Streptococcus sp. BT-003 showed that it could use crude oil as the sole source of carbon and produce organic acid, bio-gas and polysaccharide which were propitious to emulsify and reduce the viscosity of crude oil. After cultivating 8-14 h, the viscosity of crude oil reduced from 8000-15000 mPa · s to 50-250 mPa · s. The content of organic acid increased 8-15 times, and carbon dioxide and polysaccharide reached 55 ml/l and 8 g/l respectively. Paraffin and resin reduced by 60-95%, and light components increased obviously. Fluid rheology was better than before, the interfacial tension between the crude oil and water were reduced effectively. (© 2009 WILEY-VCH Verlag GmbH... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297692 Sun, 29 Mar 2009 04:00:00 +0100 2297692 http://www.medworm.com/index.php?rid=2297706&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800278 This study exemplifies the numerical and functional importance of sulfate reducing bacteria in deep-sea sedimentary environments, and incremental methodological advancements, as described herein, will continue to streamline the analysis of sulfate reducer communities in situ. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297706 Wed, 25 Mar 2009 04:00:00 +0100 2297706 http://www.medworm.com/index.php?rid=2297705&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800387 The presence of van A-containing E. faecium isolates was demonstrated in three of 77 faecal samples (3.9%) of wild rabbits recovered in Portugal. Enterococcal strains with intrinsic vancomycin resistance (van C-1 or van C-2/3 gene) were found in five (6.5%) and three (3.9%) faecal samples, respectively. The mechanisms of resistance for other antibiotics were studied in these vancomycin-resistant isolates. All van A strains showed resistance for tetracycline [with the presence of tet (L) gene, associated or not with tet (M) gene] and for erythromycin [with the presence of the erm (B) gene]. Two isolates were resistant to ciprofloxacin and one to ampicillin. Two van C-1 strains and one van C-2/3 strain were tetracycline resistant [containing the tet (M) gene associated with tet (L) gene] and... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297705 Wed, 25 Mar 2009 04:00:00 +0100 2297705 http://www.medworm.com/index.php?rid=2297704&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700376 This study could present the potential capacity of Streptomyces sp. F4 for Cd2+ bioremediation. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297704 Wed, 25 Mar 2009 04:00:00 +0100 2297704 http://www.medworm.com/index.php?rid=2297703&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800200 Rhizobium radiobacter MTCC 8161 completely decolorized methyl violet (10 mg l-1) within 8 h both at static and shaking conditions. The decolorization time increased with increasing dye concentration. The effect of different carbon and nitrogen sources on the decolorization of methyl violet was studied. The maximum decolorization was observed in the presence of sucrose (1%) and urea (1%). UV-Visible, HPLC and FTIR analysis of extracted products confirmed biodegradation of methyl violet. The significant increase in the activities of lignin peroxidase and aminopyrine N-demethylase in the cells obtained after decolorization indicated involvement of these enzymes in the decolorization process. In addition to methyl violet, this strain also shows an ability to decolorize various industrial dyes,... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297703 Wed, 25 Mar 2009 04:00:00 +0100 2297703 http://www.medworm.com/index.php?rid=2297702&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800214 A novel PCR primer pair for amplification of full-length cia B gene from thermophilic campylobacters, generated an amplicon of approximately 2.2 kilo base pairs (kbp) with all 18 isolates (n = 7 for urease-negative (UN) C. lari; n = 9 urease-positive thermophilic Campylobacter (UPTC); n = 1 C. jejuni; n = 1 C. coli). The putative open reading frame (ORF) of the cia B from C. lari isolates consisted of 1,833 bp similarly, but differing from those of C. jejuni and C. coli isolates. The putative promoter structures consisting of a semi-conserved T -rich sequence and a consensus sequence at the -10 region were identified upstream of the putative ORF in all the C. lari isolates. A start codon ATG and a probable ribosome binding site were also identified in all the isolates. In addition, two dis... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297702 Wed, 25 Mar 2009 04:00:00 +0100 2297702 http://www.medworm.com/index.php?rid=2297701&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800218 The effect of high Cu(II) concentrations on superoxide dismutase (SOD) and catalase (CAT) activity in Candida fukuyamaensis RCL-3 and Rhodotorula mucilaginosa RCL-11, previously isolated from a copper filter at a mine plant in Argentina, was studied. Addition of 0.1, 0.2 and 0.5 mM Cu(II) to the culture medium increased total SOD and CAT activity in both strains. Native polyacrylamide gel electrophoresis revealed two bands with SOD activity for C. fukuyamaensis RCL-3 and only one for R. mucilaginosa RCL-11; the three bands corresponded to MnSOD.Intracellular accumulation of copper and morphological changes was observed using electron microscopy. Dark bodies examined with transmission electron microscopy (TEM) after 48 h of incubation probably corresponded to copper deposits. The number of ... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297701 Wed, 25 Mar 2009 04:00:00 +0100 2297701 http://www.medworm.com/index.php?rid=2297700&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800223 Methanesulfonate (MSA) is one of the products of the photo-oxidation of dimethylsulfide in the atmosphere. The genes responsible for the import of MSA into the cell (msm EFGH) and for its oxidation to formaldehyde (msm ABCD) have been previously sequenced from the soil bacterium Methylosulfonomonas methylovora str. M2 while genes for an MSA monooxygenase have been sequenced from marine bacterium Marinosulfonomonas methylotropha str. TR3. We performed a sequence-based screening of the Sargasso Sea metagenome for homologues of the MSA monooxygenase (MSAMO) and MSA import genes. Our search retrieved one scaffold bearing genes with high identity to the msm ABCD cluster plus two scaffolds bearing genes highly identical to the msm EFGH operon. We increased the available data by sequencing two me... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297700 Wed, 25 Mar 2009 04:00:00 +0100 2297700 http://www.medworm.com/index.php?rid=2297699&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800232 Cloning, sequencing and characterization of nearly full-length 23S rRNA genes in 12 urease-positive thermophilic Campylobacter (UPTC) isolates were carried out using two novel PCR primer pairs. Nucleotide sequences of the 23S rRNA genes from the 12 isolates were first shown not to carry any intervening sequences (IVSs) in both the 25 and 45 helix regions. Then, two PCR primer sets were designed in silico for amplification of the helix 25 and 45 regions within 23S rRNA gene sequences from Campylobacter lari. No IVSs were identified within the 23S rRNA genes among a total of 53 isolates of C. lari, following PCR amplification, TA cloning and sequencing procedures. Intact 23S rRNA was identified in all 65 C. lari isolates, resulting in no production of the fragmented 23S rRNA. These data sugg... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297699 Wed, 25 Mar 2009 04:00:00 +0100 2297699 http://www.medworm.com/index.php?rid=2297698&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800297 In this study, diisodecyl phthalate (DIDP) was efficiently degraded by Bacillus sp. SB-007. The optimal conditions for DIDP (100 mg l-1) degradation by Bacillus sp. SB-007 in a mineral salts medium were found to be pH 7.0 at 30 °C, stirring at 200 rpm. The specific rate of DIDP degradation was found to be concentration dependent with a maximum of 4.87 mg DIDP l-1 h-1. DIDP was transformed rapidly by Bacillus sp. SB-007 with the formation of monoisodecyl phthalate and phthalic acid, which subsequently degraded further. These results highlight the potential of this bacterium for removing DIDP contaminated waste in the environment. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297698 Wed, 25 Mar 2009 04:00:00 +0100 2297698 http://www.medworm.com/index.php?rid=2297697&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800304 Isolated cell wall preparations of N. crassa bind significant levels of Ca, Mg and other divalent cations. Enzymatic treatment of the cell wall with [beta]-(1,3)-glucanase, but not with chitinase, resulted in solubilization of only the calcium-binding protein fraction. A calcium-binding protein (CaBP) was purified by metal-chelate affinity chromatography and reversed phase HPLC. CaBP has an Mr of around 6 kDa on SDS-PAGE and mass spectrometry showed that it has a molecular mass of 5744 Da. One mole of CaBP binds 2 moles of calcium and is partially inhibited (15-50%) by other divalent cations (Mg, Ni and Cu). Quenching of tryptophan fluorescence was observed upon copper binding but not calcium binding. This is a first report of a calcium binding protein from the cell wall of fungi. (© 2009... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297697 Wed, 25 Mar 2009 04:00:00 +0100 2297697 http://www.medworm.com/index.php?rid=2297696&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800306 Members of the genus Bacillus and related genera are ubiquitous in nature. However, Bacillus species isolated from marine sediments have attracted less interest respect to their terrestrial relatives. Here, we report the phylogenetic diversity of a collection of 96 Bacilli, isolated from 17 distinct stations of 5 oceanographic campaigns. The diversity was analysed by phenotypic and molecular approaches based on the amplified rDNA restriction analysis (ARDRA), amplification of the internal transcribed spacers (ITS-PCR) and on 16S rRNA sequencing. Intra-specific polymorphism was efficiently detected by biochemical analysis and ARDRA while results of ITS-PCR were in agreement with 16S rRNA sequencing. The identification results assigned 68% of the isolates to the species B. subtilis, B. liche... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297696 Wed, 25 Mar 2009 04:00:00 +0100 2297696 http://www.medworm.com/index.php?rid=2297695&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800332 Destruxins (dtx) A, B, and E, showing a variety of biological activities, are the main toxic secondary metabolites of the entomopathogenous ascomycete Metarhizium anisopliae Bipesco 5, a widely used biocontrol production strain. Dynamics of dtx biosynthesis were monitored during liquid fermentation in a chemically defined medium. During shake flask cultivation with excess carbon, nitrogen and phosphate, approximately 50, 20, and 100 mg l-1 dtx A, B, and E were produced after 12 d. Destruxins were produced during exponential growth phase and in the stationary phase. Carbon exhaustion in the culture broth was demonstrated to affect destruxin production to a minor degree: Absolute dtx amounts in the liquid increased also after glucose exhaustion; dtx amounts referred to biomass increased furt... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297695 Wed, 25 Mar 2009 04:00:00 +0100 2297695 http://www.medworm.com/index.php?rid=2297694&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800347 Pycnoporus sanguineus is a white-rot fungus that produces ligninolytic enzymes such as laccases. These enzymes can endure temperatures as high as 60 °C and are useful for pulp bleaching, dye decolorization and phenolic degradation.Laccase production by fungi depends not only on the carbon and nitrogen sources but also on the nitrogen concentration of the culture medium. In this work, we examined the effect of four carbon sources (maltose, glucose, fructose and sucrose) and four nitrogen sources (ammonium tartrate, sodium nitrate, asparagine and yeast extract) on the activity of laccase from Pycnoporus sanguineus. All carbon and nitrogen sources exhibited a strong influence on laccase activity, a sucrose-asparagine medium providing the best results (320 mU/ml). Moreover, using an asparagin... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297694 Wed, 25 Mar 2009 04:00:00 +0100 2297694 http://www.medworm.com/index.php?rid=2297693&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800355 Chickpea plants with nodules were collected from 32 different farmers' fields of eight districts of Haryana state. In total, 137 mesorhizobial isolations were made from these nodules and authenticated. Finally, 50 mesorhizobia were selected based on nodulation test, growth characteristics, and site of sampling. The molecular diversity of the mesorhizobial population was assessed by PCR-amplified ERIC profiles as well as RFLP of 16S rDNA. Considerable molecular diversity in Haryana soils was observed. Chickpea rhizobia were grouped into six different clusters at the 70% similarity level by both methodologies, but clustering of the strains was different. Considering that each cluster represented a mesorhizobial genotype, Haryana soils showed a high richness index (0.46), and RFLP analysis sh... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2297693 Wed, 25 Mar 2009 04:00:00 +0100 2297693 http://www.medworm.com/index.php?rid=2185683&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800047 From 16 samples of traditional fermented koumiss collected in Inner Mongolia Autonomous Region of China, forty-eight lactobacilli strains were isolated and phenotypically characterized by their abilities to ferment different carbohydrates and by additional biochemical tests. The dominant lactobacilli species were identified as L. casei (17 strains), L. helveticus (10 strains) and L. plantarum (8 strains), with a lower frequency of isolation for L. coryniformis subsp. coryniformis (5 strains), L. paracasei (3 strains), L. kefiranofaciens (2 strains), L. curvatus (1 strain), L. fermentum (1 strain) and W. kandleri (1 strain). The pH values of all these samples were ranging from 3.37 to 3.94. In isolates, L. casei Zhang, L. helveticus ZL12-1, and L. plantarum BX6-6 were selected as potentiall... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2185683 Fri, 13 Feb 2009 05:00:00 +0100 2185683 http://www.medworm.com/index.php?rid=2185682&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800130 Assessment of nickel contents in soil samples in Kuwait indicated only a minor difference in concentration in hydrocarbon-contaminated (86 mg kg-1 soil) and non-contaminated soils (84 mg kg-1 soil). The potential inhibitory effects of nickel on the number of hydrocarbon degraders, and hydrocarbon utilization were investigated over a wide range of nickel concentrations to span concentrations observed in the soil. Nickel addition, as nickel sulphate, to soil samples reduced the number of hydrocarbon degraders in all samples by a wide range (15-96%) depending on concentration and the hydrocarbon substrate utilized. Similarly, the metabolic activities were affected as observed in mineralization (3-60%) of soils amended with various concentrations of nickel. The inhibitive effects of nickel on ... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2185682 Fri, 13 Feb 2009 05:00:00 +0100 2185682 http://www.medworm.com/index.php?rid=2185681&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800152 Microorganisms such as bacteria and molds produce an enormous variety of volatile metabolites. To determine whether typical microbial volatile metabolites can be used as indicator compounds for the detection of hidden mold in indoor environments, we examined 14 typical indoor fungal strains for their growth rates and their capability to produce volatile organic compounds (VOC) on standard clinical media and on agar medium made from building materials. Air samples from Headspace Chambers (HSC) were adsorbed daily on Tenax TA tubes and analyzed by thermal desorption gas chromatography and mass spectrometry. In parallel, metabolic activity was measured by determining oxygen demand, the microbial biomass was assessed by dry weighing. Profiling of the volatile metabolites showed that VOC produc... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2185681 Fri, 13 Feb 2009 05:00:00 +0100 2185681 http://www.medworm.com/index.php?rid=2185680&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800185 Ten Lactobacillus strains originally isolated from Thai fruits and vegetables fermentation were characterized by various phenotypic and genotypic methods. The phenotypic analysis using the method of carbohydrate fermentation patterns (API50CHL) revealed that the isolates belonged to the L. plantarum species. This was further confirmed by 16S rRNA gene sequencing. Multilocus sequence typing (MLST) revealed a strongly clonal population structure and a low genotypic diversity in this collection. However, the analyzed L. plantarum population demonstrated a higher level of diversification after API50CHL that reflects the role of available carbohydrate sources in bacterial evolution. Our results support the postulate that a combination of conventional biochemical and genotyping methods allows a ... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2185680 Fri, 13 Feb 2009 05:00:00 +0100 2185680 http://www.medworm.com/index.php?rid=2185679&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800196 In this study, the biofilm matrix of four S. epidermidis clinical isolates was extracted and the polysaccharides and proteins content was quantified. The results were correlated with the total biofilm biomass (determined by crystal violet assay) and cellular metabolic activity (evaluated with XTT reduction assay). According to the results, the exopolymers studied play an important role not only on structure and biofilm biomass but also on cellular activity. Thus, the strain forming biofilms with the highest level of polysaccharides (S. epidermidis 1457) also formed thicker biofilms but with the lowest metabolic activity. The protein concentration also varied among strains, with the biofilm matrix of S. epidermidis 9142 presenting a higher concentration of proteins comparing to the remainin... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2185679 Fri, 13 Feb 2009 05:00:00 +0100 2185679 http://www.medworm.com/index.php?rid=2185678&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800212 Six biocides resistant isolates were isolated from dental unit water lines (DUWL) in Pakistan. All isolates could tolerate 150 [mu]g ml-1 of biocides (5.25% sodium hypocholrite, 35% H2O2, 4% tween 20, 1% povidine iodine, 0.2% chlorohexidine gluconate, 1% ethylene di-amino tetra acetic acid and 1% phenol) on l-agar and 100 [mu]g ml-1 in l-broth. The growth rate of all isolates was determined by generating growth curves at 37 °C for 48 h. The isolates were found to differ in growth rates with lag phase varying from (4-6 h) in biocides supplemented media compared to 2-4 h in biocides free medium. They have wide temperatures (24-42 °C) and pH (5-9) ranges. Traditional ways of identification of bacteria by phenotypic characteristics were accomplished by phenotypic and biochemical characteriza... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2185678 Fri, 13 Feb 2009 05:00:00 +0100 2185678 http://www.medworm.com/index.php?rid=2176161&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800337 Two dimensional gas chromatography coupled to time-of-flight mass spectrometry (GCxGC-TOF-MS) is a promising technique to overcome limits of complex metabolome analysis using one dimensional GC-TOF-MS. Especially at the stage of data export and data mining, however, convenient procedures to cope with the complexity of GCxGC-TOF-MS data are still in development. Here, we present a high sample throughput protocol exploiting first and second retention index for spectral library search and subsequent construction of a high dimensional data matrix useful for statistical analysis. The method was applied to the analysis of 13C-labelling experiments in the unicellular green alga Chlamydomonas reinhardtii. We developed a rapid sampling and extraction procedure for Chlamydomonas reinhardtii laborato... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2176161 Tue, 10 Feb 2009 05:00:00 +0100 2176161 http://www.medworm.com/index.php?rid=2176160&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800339 Diatoms contribute a large proportion to the worldwide primary production and are particularly effective in fixing carbon dioxide. Possibly because diatom plastids originate from a secondary endocytobiosis, their cellular structure is more complex and metabolic pathways are rearranged within diatom cells compared to cells containing primary plastids. We annotated genes encoding isozymes of the reductive and oxidative pentose phosphate pathways in the genomes of the centric diatom Thalassiosira pseudonana and the pennate diatom Phaeodactylum tricornutum and bioinformatically inferred their intracellular distribution. Prediction results were confirmed by fusion of selected presequences to Green Fluorescent Protein and expression of these constructs in P. tricornutum. Calvin cycle enzymes for... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=2176160 Tue, 10 Feb 2009 05:00:00 +0100 2176160 http://www.medworm.com/index.php?rid=1983162&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800186 Two different types of fed-batch fermentation were investigated to improve production yields of the Lip2 extracellular lipase in Y. lipolytica mutant-strain LgX64.81 grown in a 20l bioreactor. Compare to batch cultures, culture feeding with the complete medium led to a 2-fold increased lipase production (2016 ± 76 U ml-1) whereas addition of a combination of glucose and olive oil led to a 3-fold increase. The high level of lipase production obtained on glucose media with Y. lipolytica LgX64.81 could be related to its phenotype i.e. a lower sensibility to glucose catabolite repression due to a modification in the level of HXK1 expression. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1983162 Mon, 24 Nov 2008 05:00:00 +0100 1983162 http://www.medworm.com/index.php?rid=1983161&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800102 This review surveys the chemical and biological literature dealing with the isolation, structure elucidation and bioactivity of diterpenoids from the fruiting bodies of macromycetes, concentrating on work that has appeared in the literature up to December 2007. In addition, this paper examines the research of diterpenoids produced by macromycetes grown in mycelial culture and the culture conditions for the fermentation of macromycetes. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1983161 Mon, 24 Nov 2008 05:00:00 +0100 1983161 http://www.medworm.com/index.php?rid=1983160&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800231 Plant-pathogenic fungi produce an array of extracellular hydrolytic enzymes that enable them to penetrate and infect the host tissue; these enzymes are collectively called cell wall-degrading enzymes (CWDE). They may contribute to pathogenesis by degrading wax, cuticle and cell walls, thus aiding tissue invasion and pathogen dissemination. Furthermore, they can act as elicitors of host defense reaction.Fusarium head blight (FHB) is a disease caused principally by Fusarium graminearum on crops, occurring all over the world. Important economic losses on wheat-growing areas have been registered by altering quality parameters of grains. Significant progress has been made in understanding the infection process from F. graminearum on wheat, based on genomic technologies. The virulence degree of ... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1983160 Mon, 24 Nov 2008 05:00:00 +0100 1983160 http://www.medworm.com/index.php?rid=1983159&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800060 This study was conducted to determine the prevalence rate of VTEC in slaughtered sheep and goats and to evaluate the contamination rate of VTEC in slaughterhouses and butchers' shops in southern Jordan. 201 E. coli isolates from animals' faecal samples and 33 E. coli isolates from slaughterhouse/butcher shop samples were characterized by multiplex PCR (mPCR) reaction for detection of stx1, stx2, eae A and E-hly A virulent genes. Twenty-six virulent E. coli isolates were characterized by mPCR to seven different virulent patterns: stx1, stx1+stx2, stx1+eae A, stx1+E-hly A, stx1+eae A+E-hly A, eae A and E-hly A. It was found that VTEC comprised 6.4% and 21% of the total E. coli isolates from slaughtered small ruminants and slaughterhouses/ butchers' shops, respectively. The VTEC comprised 76.... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1983159 Mon, 24 Nov 2008 05:00:00 +0100 1983159 http://www.medworm.com/index.php?rid=1983158&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800139 In order to investigate the effect of poly-3-hydroxybutyrate synthase mutation (phbC) on the synthesis of exopolysaccharides (EPS) and glycogen, on the symbiotic properties and on the survival under specific conditions of Ensifer meliloti (formerly Sinorhizobium), a new stable phbC mutant of Ensifer meliloti 41 was isolated and characterized.Under poly-3-hydroxybutyrate accumulation conditions, the phbC -minus mutant (strain 41003) accumulates more glycogen and less exopolysaccharides as compared to the wild-type strain, and grows poorly in pyruvate as carbon source. The inactivation of aniA, encoding for a global carbon flux regulator, restores in E. meliloti 41003 the ability to grow on pyruvate, indicating a new role for this gene. Survival studies of E. meliloti 41 and 41003 under carb... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1983158 Mon, 24 Nov 2008 05:00:00 +0100 1983158 http://www.medworm.com/index.php?rid=1983157&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800156 Extracellular enzymes produced by Beauveria bassiana, are believed to play a key role in cuticle hydrolysis. Enzyme production and pathogenicity has been found to be positively correlated. Twenty-eight isolates of B. bassiana, collected from different geographical regions and host ranges were characterized by in vitro extracellular enzyme production and SDS-PAGE techniques for discerning biochemical basis for virulence among the different isolates. In vitro analysis of extracellular enzymes like protease, amylase, caseinase, chitinase and lipase was undertaken in an attempt to understand their relevance to virulence of the isolates. The different isolates of B. bassiana were evaluated for virulence to the second instar larvae of Helicoverpa armigera in laboratory bioassays. SDS-PAGE of tot... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1983157 Mon, 24 Nov 2008 05:00:00 +0100 1983157 http://www.medworm.com/index.php?rid=1983156&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800182 Sixteen Bacillus thuringiensis (Bt) strains were screened for their anti-insect, antibacterial and antifungal determinants by phenotypic tests and PCR targeting major insecticidal proteins and complements, chitinases, lactonases, [beta]-1,3-glucanases and zwittermicinA. Six strains had genes of at least two major insecticidal toxins and of insecticidal complements. With regard to fungal biocontrol, all the strains inhibited Fusarium oxysporum and Aspergillus flavus growth and four strains had all or most of the antifungal determinants examined, with strain Bt HD932 showing the widest antifungal activity spectrum. Autolysins, bacteriocin and AHL-lactonases were produced by all or most of the tested strains with different activity spectra including pathogens like Listeria monocytogenes. Safe... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1983156 Mon, 24 Nov 2008 05:00:00 +0100 1983156 http://www.medworm.com/index.php?rid=1983155&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800194 13 morphologically distinct strains of thermophilic bacteria isolated from a hot spring site in Garhwal region of Indian Himalaya have been characterized and identified using phenotypic and genotypic characters. All the strains developed circular to irregular colonies between 2-3 mm on Tryptone Yeast extract (TY) agar plates at 65 °C following 24-36 h incubation. In TY broth, facultative bacterial growth was observed within 12-16 h of incubation at 65 °C. The bacterial strains could tolerate a temperature range between 40-45 °C to 85-90 °C (optimum 65-70 °C) and pH between 4-11 (optimum 6-8). The cell morphology varied from short to long rods arranged in single, diplobacilli (in V or L shape) or short or long spiral chains with coiling. The bacterial strains varied in respect of their... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1983155 Mon, 24 Nov 2008 05:00:00 +0100 1983155 http://www.medworm.com/index.php?rid=1983154&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800211 A new method for procedures using a computer to find out useful candidates for probes discriminating a certain group in higher ranks of bacteria is presented. In order to make the search of the probes systematic, two indices are proposed, i.e., Coincidence Ratio Inside Group (CRIG) and Coincidence Number Outside Group (CNOG), which indicate the rate of matching of probes inside or outside group respectively. Using two indices, allowance grades indicating usefulness of arbitrary sequence as a probe are defined from 9 (5 in species) to 0. Its application to the 16S rRNA gene of 2206 bacterial species selected from the Ribosomal Database Project (RDP-II) (J.R. Cole et al., Nucleic Acids Res. 31: 442-443, 2003) is shown. Small nucleotide sequences of the length L (L = 15, 19, 23) were searched... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1983154 Mon, 24 Nov 2008 05:00:00 +0100 1983154 http://www.medworm.com/index.php?rid=1983153&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800222 Bacteriorhodopsin (bR) is well recognized for its applied values. We observed that the bottleneck associated with the use of different peptones for bR production was linked to the presence of tryptophan (Trp). Trp at 0.36 mM in the culture medium inhibits bR formation. The results obtained in this study demonstrate that bR content (mg l-1) of Halorubrum sodomense A01 decreased to 2.9 mg l-1 in 0.36 mM Trp compared to control (0.11 mM Trp) where 12.3 mg l-1 of bR was obtained. Our results provide useful information for the design of production conditions for bR to be used in applied settings. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1983153 Mon, 24 Nov 2008 05:00:00 +0100 1983153 http://www.medworm.com/index.php?rid=1983152&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800239 This work provides quantitative information on Cr(VI) reduction in soil samples by an indigenous actinomycete. Streptomyces sp. MC1, previously isolated from sugarcane, has shown ability to reduce Cr(VI) in liquid minimal medium. A reduction of 100 and 75% was obtained at initial Cr(VI) concentrations of 5 and 50 mg l-1, respectively, after 48 h of incubation. Bioremediation ability of Streptomyces sp. MC1 was assayed in soil extracts and soil samples. Relative growth of Streptomyces sp. MC1 was 77 and 38% when grown in soil extract with 10 and 50 mg l-1 of Cr(VI), respectively. MC1 was able to reduce 30% of Cr(VI) after 96 h of incubation with 10 mg l-1 of Cr(VI), and reduction coincided with the exponential growth phase at pH 7 and 30 °C.In soil samples, Streptomyces sp. MC1 was able to... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1983152 Mon, 24 Nov 2008 05:00:00 +0100 1983152 http://www.medworm.com/index.php?rid=1808007&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800065 Proteins expressed by the bacterial cold shock genes are highly conserved at sequence level and perform various biological functions in both the cold-stressed and normal cells. To study the effects of various agents on the cold shock genes of Staphylococcus aureus, we have cloned the upstream region of cspC from S. aureus Newman and found that the above region possesses appreciable promoter (Pc) activity even at 37 ºC. A reporter S. aureus strain CHANDA2, constructed by inserting the Pc -lacZ transcriptional fusion into S. aureus RN4220 genome, was found to express very low level of [beta] -galactosidase after cold shock, indicating that low temperature induces Pc very weakly. Interestingly, transcription from Pc was induced very strongly by several antibiotics, hydrogen peroxide and arse... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1808007 Fri, 19 Sep 2008 04:00:00 +0100 1808007 http://www.medworm.com/index.php?rid=1796318&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800093 Smallanthus sonchifolius is a traditional Andean plant which has been cultured mainly in Brazil, Japan and New Zealand due to its medicinal properties. A study of the endophytic fungi associated to the plant was carried out in order to characterize new cytotoxic agents. Thirty two fungal strains were isolated and submitted to cultivation and extraction producing 186 extracts. Of these, 12% displayed moderate to high cytotoxic activities and were considered promising anticancer compound sources. The ethyl acetate fractions of Nigrospora sphaerica and Phoma betae liquid fermentations contained the synergistic compounds 8-hydroxy-6-methoxy-3-methylisocoumarin and (22E,24R)-ergosta-4,6,8(14),22-tetraen-3-one which are potential compounds for drug discovery. Another isolated compound, pimara-7,... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1796318 Wed, 17 Sep 2008 04:00:00 +0100 1796318 http://www.medworm.com/index.php?rid=1796324&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800146 Dalbavancin is a new new semisynthetic teicoplanin-related lipoglycopeptide with activity against gram-positive organisms. We investigated the activity of dalbavancin against faecal enterococci isolates from wild animals, pets, poultry and healthy humans in Portugal.The in vitro activity of dalbavancin was determined by the microbroth dilution method according to the Clinical Laboratory Standards Institute (CLSI) guidelines in 589 enterococci of different species and origins. All vancomycin-susceptible Enterococcus spp. were inhibited by [le]0.25 mg/l dalbavancin. Although vancomycin-resistant-enterococci (VRE) showed higher dalbavancin MIC values (16 mg/l), the isolates that exhibited the VanC resistance phenotype were inhibited at dalbavancin concentrations [le]0.125 mg/l. Only van A iso... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1796324 Tue, 16 Sep 2008 04:00:00 +0100 1796324 http://www.medworm.com/index.php?rid=1796323&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800167 A phenol degrading yeast isolate was identified and characterized from the soil sample collected from a landfill site, in Ahmedabad, India, by plating the soil dilutions on Sabouraud's Dextrose Agar. The microscopic studies and biochemical tests indicated the isolate to be Saccharomyces cerevisiae. The phenol degrading potential of the isolate was measured by inoculation of pure culture in the mineral medium containing various phenol concentrations ranging from 100 to 800 mg l-1 and monitoring phenol disappearance rate at regular intervals of time. Growth of the isolate in mineral medium with various phenol concentrations was monitored by measuring the turbidity (OD600 nm). The results showed that the isolated yeast was tolerant to phenol up to 800 mg-1. The phenol degradation ranged from ... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1796323 Tue, 16 Sep 2008 04:00:00 +0100 1796323 http://www.medworm.com/index.php?rid=1796322&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800197 The small molecular mass antifungal protein of Penicillium chrysogenum (PAF) inhibited the growths of two obligate biotrophic fungal pathogens, Blumeria graminis f. sp. hordei and Puccinia recondita f.sp. tritici and, hence, mitigated the symptoms of barley powdery mildew and wheat leaf rust infections, respectively. PAF also affected adversely the germination of B. graminis conidia and P. recondita uredospores causing degenerative branching of germ tubes. Since powdery mildews and rusts cause serious economic losses the potential applicability of PAF to control these plant diseases is promising. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1796322 Tue, 16 Sep 2008 04:00:00 +0100 1796322 http://www.medworm.com/index.php?rid=1796321&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800090 Phytoremediation i.e. the use of plants to adsorb, accumulate or detoxify contaminants is an emerging area of interest. A viable technology needs optimum biomass production in metal contaminated soil. Five strains of microbes were selected after testing their potential as plant growth promoters, on the basis of their phosphate solubilization ability, IAA, siderophore and HCN production and biocontrol potentials. They were examined for growth in synthetic medium supplemented with nickel and their MIC (2 mM) was determined. These isolates were also able to grow and produce siderophores in presence of heavy metals like Ni, Zn and Cd. A positive response of bacterial inoculants was observed in chickpea plants towards toxic effect of nickel present in soil at different concentration (0, 1 and 2... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1796321 Tue, 16 Sep 2008 04:00:00 +0100 1796321 http://www.medworm.com/index.php?rid=1796320&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800121 Four Collections comprising 507 strains of Bacillus thuringiensis have been analysed in this study. A different ecological origin characterizes each collection. Collection No. 1 was established from soil, dust, and grain samples from Spanish agricultural and non-cultivated soil, silos, and mills. Collection No. 2 is the result of a screening in olive-crop related environments in Spain. Collection No. 3 is made up of strains isolated from potato-growing areas in Bolivia. Collection No. 4 has been generated for this study and includes strains collected from diverse types of samples belonging to several habitats from Spain and Mexico. Crystal morphologies and cry1A and cry2 gene content were assessed for all isolates from each collection. In the 507 strains, the most common crystal morphology... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1796320 Tue, 16 Sep 2008 04:00:00 +0100 1796320 http://www.medworm.com/index.php?rid=1796319&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800123 In this study, we found that incubation of the S. cerevisiae cells with PEG was not only required for the PEG-dependent transformation but also enhanced transformation, suggesting that PEG might cause an intracellular response. To understand the response, microarray and metabolome analyses were conducted. We found that incubation of the cells without PEG caused up-regulation of several genes, including those which are involved in carbon source metabolisms, e.g. fatty acid metabolism, yielding acetyl-CoA and those involved in stress-response. Contrary to this, incubation of the cells with PEG gave no transcriptional change. These microarray data were supported by the results of metabolome analysis for anionic metabolites, implying that the physical effect of PEG on cell membrane, rather tha... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1796319 Tue, 16 Sep 2008 04:00:00 +0100 1796319 http://www.medworm.com/index.php?rid=1789663&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800119 This study examined four lactobacilli isolated from pig feces. Two hundred lactic acid bacteria strains were obtained from pig feces using selective culture media (with vancomycin and bromocresol green; termed LAMVAB agar). Microscopy, the catalase test, Gram-staining, and RAPD-PCR analysis were used to group the bacteria into 20 related clusters. Phenotypic analysis using the API 50 CH test and genotypic analysis of 16S rDNA sequences identified these clusters as representing single strains of each of Lactobacillus fermentum, Lactobacillus salivarius, Lactobacillus plantarum, and Lactobacillus reuteri. Bacterial survival under the conditions of low pH (2.0) and high concentration (5.0%, w/v) of bile salt was much better than that of the reference strain (Lactobacillus acidophilus ATCC 331... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1789663 Sun, 14 Sep 2008 04:00:00 +0100 1789663 http://www.medworm.com/index.php?rid=1787434&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800097 Bacillibactin is a catecholate type siderophore produced by Bacillus subtilis. This review focuses on the bacillibactin non-ribosomal synthesis, transport and regulation by ferric uptake repressor (Fur). Five genes are involved in the biosynthetic pathway for bacillibactin (dhbACEF). The uptake of bacillibactin requires the FeuABC transporter, inner-membrane permease, FepDG and YusV ATPase and an esterase encoding gene. Fur is the major iron-controlled transcriptional regulator in B. subtilis, which acts as an iron-dependent repressor of the dhb operon in vivo while an iron-independent repressor in vitro. We also interpreted the available knowledge about the interaction of metal ions with Fur. Knowledge of the Fur regulon will be useful in interpreting other global analysis of transcriptio... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1787434 Thu, 11 Sep 2008 04:00:00 +0100 1787434 http://www.medworm.com/index.php?rid=1787433&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700380 Thiosulfate oxidizing bacteria isolated from crop plants were tested for their traits related to plant growth promotion and their ability to solubilize Morocco rock phosphate (RP) through oxidation of thiosulfate to sulfuric acid. All the tested strains grew in Nfb medium (except Dyella ginsengisoli) and possessed [beta]-1,3 glucanase activity (except Burkholderia kururiensis). Of the fourteen tested strains, 2 were found positive for siderophore production, 3 each for phytohormones (IAA), and salicylic acid production. Based on qualitative and quantitative assays, 5 strains were found to efficiently solubilize tri-calcium phosphate in Pikovskaya's medium. Nine strains exhibited ACC (1-aminocyclopropane-1-carboxylate) deaminase activity. In gnotobiotic experiments, Pandoraea sputorum ATSB2... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1787433 Thu, 11 Sep 2008 04:00:00 +0100 1787433 http://www.medworm.com/index.php?rid=1787432&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800030 We report here a rapid and highly reproducible swarm plate protocol for P. aeruginosa and show how different key parameters affect this type of motility (i.e. agar %, drying time under laminar flow, incubation temperature and pH). Results reported here will help to standardize swarming motility assays and develop effective swarm plate protocols for other bacterial species. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1787432 Thu, 11 Sep 2008 04:00:00 +0100 1787432 http://www.medworm.com/index.php?rid=1787431&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800059 Azotobacter are the favored bioinoculants being promoted for cotton crop in India. In order to develop bioinoculants, both metabolic fingerprinting and genetic fingerprinting have been used to study the diversity among Azotobacter spp. isolated from four different cotton-wheat cropping regions of India. On the basis of acetylene reduction, indole acetic acid production and ammonia excretion, from 76 free-living diazotrophs isolated from the rhizospheric soil of cotton, 20 efficient isolates were selected for further studies. Morphological characterization indicated a close resemblance of these isolates to Azotobacter spp. BIOLOG cataloguing divided them into two main groups, but amplified ribosomal DNA restriction analysis clustered the isolates from the four regions having different soil ... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1787431 Thu, 11 Sep 2008 04:00:00 +0100 1787431 http://www.medworm.com/index.php?rid=1787430&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800073 This study elucidates the multifarious role of strain SM3 in plant growth promotion and its metal mobilizing potential. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1787430 Thu, 11 Sep 2008 04:00:00 +0100 1787430 http://www.medworm.com/index.php?rid=1787429&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800114 tert -Butylhydroperoxide (t BOOH) tolerant Candida albicans mutants developed from clinical isolates were characterized with increased tolerance of the oxidative stress generating agents t BOOH and H2O2, continuous induction of the antioxidative defence system, reduced pseudohypha and hypha-forming capabilities, decreased phospholipase secretion and delayed growth in Sabouraud dextrose agar and broth media. Changes in antimycotic (fluconazole, voriconazole, amphotericin B, 5-fluorocytosine) tolerances as well as in total and cytochrome c-dependent respirations showed versatile patterns, meanwhile the intensified alternative oxidase-dependent respiration of the mutants indicated that this respiratory pathway was an important element of the antioxidative defence in general. Because the pheno... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1787429 Thu, 11 Sep 2008 04:00:00 +0100 1787429 http://www.medworm.com/index.php?rid=1787428&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800116 The DNA fragment of heat shock genes (hrcA-grpE-dnaK-dnaJ) containing complete hrcA-grpE-dnaK operon and the transcription unit of dnaJ was cloned, sequensed and analyzed from Bacillus megaterium RF5. The sequence of hrcA, grpE and dnaJ were first time reported, and their coding products exibit 60%, 63% and 81% of identities to the homologs of B. subtilis. A [sigma]A-type promoter of Gram-positive bacteria (PA1) and a terminator were located upstream of the hrcA and downstream of dnaK, and a Controlling inverted repeat of chaperone expression element (CIRCE) was identified between PA1 and hrcA. Another [sigma]A-type promoter (PA2) and a terminator were found upstream and downstream of dnaJ, indicating B. megaterium has a transcription unit containing a single gene dnaJ. The structure of dn... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1787428 Thu, 11 Sep 2008 04:00:00 +0100 1787428 http://www.medworm.com/index.php?rid=1741156&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800046 Bacterial strain Exiguobacterium sp. ZM-2 isolated from agricultural soil irrigated with tannery effluents, was examined for its resistance to hexavalent chromium. Exiguobacterium sp. ZM-2 could resist 12.37 mM of potassium chromate. The isolate was also found resistant to other heavy metal ions. Exiguobacterium sp. ZM-2 was able to reduce 500 [mu]M hexavalent chromium completely within 56 h under in vitro conditions. Chromate reduction was severely affected in presence of metabolic inhibitors, sodium cyanide and sodium azide. No chromate reduction was observed in presence of 1 mM sodium cyanide while only 17% of 250 [mu]M chromate was reduced when medium contained 1 mM sodium azide. A 10 mM sodium sulphate inhibited hexavalent chromium reduction up to 35%. On the other hand, use of 1 mM 2... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741156 Sat, 30 Aug 2008 04:00:00 +0100 1741156 http://www.medworm.com/index.php?rid=1741169&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700281 In this study, Paenibacillus polymyxa GS01 was isolated from the interior of the roots of Korean cultivars of ginseng (Panax ginseng C. A. Meyer). Two cellulase genes, cel 5A and cel 5B, were cloned from GS01, and encode 334 aa and 573 aa proteins, respectively. Cel5A and Cel5B each contain a glycosyl hydrolase family 5 (GH5) catalytic domain. The molecular mass of Cel5A and Cel5B were estimated to be 33 kDa and 61 kDa, respectively, by CMC-SDS-PAGE. When purified from Escherichia coli Cel5A and Cel5B both displayed cellulase activity with pH optima of 7.0 and 6.0, respectively and shared a temperature optimum of 50 °C. Neither enzyme had detectable xylanase, lichenase, or mannase activity, in contrast to the multifunctional Cel44C-Man26A enzyme of P. polymyxa which displays cellulase, xy... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741169 Fri, 29 Aug 2008 04:00:00 +0100 1741169 http://www.medworm.com/index.php?rid=1741168&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700327 The production of antimicrobial, haemolytic and gelatinase activities was tested in 67 enterococci (39 E. faecium, 24 E. hirae, 2 E. faecalis, and 2 Enterococcus spp.), recovered from faecal samples of wild boars. In addition, the presence of genes encoding bacteriocin and virulence factors was also analysed by PCR and sequencing. Production of antimicrobial activity was checked in all enterococci against 9 indicator bacteria and it was detected in 11 E. faecium isolates (16.5%); eight and two of them harboured the genes encoding enterocin A + enterocin B and enterocin L50A/B, respectively. Sixty-seven per cent of our enterococci harboured different combinations of genes of the cyl operon, but none of them contained the complete cyl LLLSABM operon, necessary for cytolysin expression. The p... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741168 Fri, 29 Aug 2008 04:00:00 +0100 1741168 http://www.medworm.com/index.php?rid=1741167&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700341 Harmless bacteria inhabiting inner plant tissues are termed endophytes. Population fluctuations in the endophytic bacterium Pantoea agglomerans associated with two species of field cultured citrus plants were monitored over a two-year period. The results demonstrated that populations of P. agglomerans fluctuated in Citrus reticulata but not C. sinensis. A cryptic plasmid pPA3.0 (2.9 kb) was identified in 35 out of 44 endophytic isolates of P. agglomerans and was subsequently sequenced. The origins of replication were identified and nine out of 18 open reading frames (ORFs) revealed homology with described proteins. Notably, two ORFs were related to cellular transport systems and plasmid maintenance. Plasmid pPA3.0 was cloned and the gfp gene inserted to generate the pPAGFP vector. The vect... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741167 Fri, 29 Aug 2008 04:00:00 +0100 1741167 http://www.medworm.com/index.php?rid=1741166&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700349 We investigated the production of extracellular elastase, acid proteinase and phospholipase enzyme activities in clinical isolates of Aspergillus fumigatus, Aspergillus flavus and Aspergillus niger and any possible correlation between the existence of these enzymes and development of invasive aspergillosis. A total of 73 strains (45 A. fumigatus, 23 A. flavus, 5 A. niger) isolated from patients with invasive aspergillosis (n = 55), superficial aspergillosis (n = 5), allergic bronchopulmonary aspergillosis (n = 1), and from those colonized with Aspergillus (n = 12) were included in the study. The enzymatic activities were tested on solid media supplemented with the corresponding substrates. Elastase activity was detected in 95.6, 82.6, and 0% of A. fumigatus, A. flavus, and A. niger isolate... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741166 Fri, 29 Aug 2008 04:00:00 +0100 1741166 http://www.medworm.com/index.php?rid=1741165&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700389 A defined medium is essential for studying nutritional requirements of microorganisms and for selective supplementation of necessary substances. Hemin is an essential ingredient for growth of Leishmania tarentolae, but tends to precipitate in aqueous solutions without further stabilization. These aggregates disturb the measurement of the optical density or the cell density and the following downstream processing. Therefore, we were looking for stabilizing substances and established a PEG-hemin-solution, which avoided flocculation and allowed the cultivation of L. tarentolae in a medium, which we termed SFP(II) medium. With addition of RNA from Saccharomyces cerevisiae to SFP(II) medium the SFP(III) medium was established. In this medium, the specific cell division rate was increased (0.103... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741165 Fri, 29 Aug 2008 04:00:00 +0100 1741165 http://www.medworm.com/index.php?rid=1741164&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800006 Four different morphotypes of halotolerant Penicillium isolated from mangroves and salterns, selected on the basis of their morphological dissimilarities, namely, monoverticillate, biverticillate symmetric, biverticillate asymmetric and terverticillate, were studied for their response to the presence of heavy metals - lead, copper and cadmium salts. Lead was the most easily tolerated of the heavy metals tested, and caused the least variations in cultural and morphological characteristics, while cadmium was the most toxic, causing significant cultural and morphological variations. More striking was the observation that resistance to the heavy metals was highest by the terverticillate Penicillium, decreasing in the biverticillate isolates, the monoverticillate isolate showing the least resis... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741164 Fri, 29 Aug 2008 04:00:00 +0100 1741164 http://www.medworm.com/index.php?rid=1741163&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800024 Trehalose production by a novel strain of Brevibacterium sp. SY361 was optimized in submerged fermentation. Different chemical and physical parameters such as carbon and nitrogen sources, inoculum level, initial pH, incubation temperature, aeration and time-course of fermentation, were studied in order to increase trehalose productivity. An optimal production medium containing 3% (w/v) glucose, 0.9% (v/v) corn steep liquor, 0.5% (w/v) KH2PO4 and 0.4% (w/v) MgSO4·7 H2O was found suitable for trehalose production. An optimal volume of medium in a 500 ml flask was 80 ml. The optimal levels of other parameters were 4.0% (v/v) of inoculum, initial pH of 6.0, incubation temperature of 28-32 °C and time-course of 60 h. Optimized parameters gave a maximum trehalose of 12.2 mg/ml with a conversio... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741163 Fri, 29 Aug 2008 04:00:00 +0100 1741163 http://www.medworm.com/index.php?rid=1741162&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800027 In this study, we employed an intranasally challenged plague model in mice for investigating the kinetics of the disease progression by transcriptional profiling of Y. pestis and mice using qRT-PCR and microarray, respectively. The increasing transcription of important virulence genes of Y. pestis and of mice genes involving in immune and inflammatory defensive responses, and responses to stimuli, presents an overview of interaction between Y. pestis and mice during development of pneumonic plague. The early and persisting up-regulation of caf 1, psa A and lcr V in vivo indicated their role in resisting the host innate immune responses. The up-regulation of fur, ybt A and hms H in vivo reflected the ability of Y. pestis for acquiring iron. The transcription regulators, including pho P, oxy... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741162 Fri, 29 Aug 2008 04:00:00 +0100 1741162 http://www.medworm.com/index.php?rid=1741161&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800036 Forty three strains were isolated from knots induced by Pseudomonas savastanoi in different olive cultivars. All the selected bacteria were shown to produce variable amounts of the plant growth hormone indole-3-acetic acid (IAA). Amplification of the intergenic transcribed spacers (ITS) between 16S and 23S rDNA genes, allowed the clustering of the isolates into seven distinct groups. All isolates from ITS group 1 were positive to the Pseudomonas savastanoi pv. savastanoi specific iaa L gene as shown by PCR. Partial sequencing of 16S rDNA gene confirmed the identity of these isolates to Pseudomonas savastanoi strains and allowed to tentatively assign the other isolates from the remaining ITS groups to Pantoea oleae/agglomerans, Burkholderia cepacia, Pseudomonas putida, Stenotrophomonas malt... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741161 Fri, 29 Aug 2008 04:00:00 +0100 1741161 http://www.medworm.com/index.php?rid=1741160&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800070 The genus Anabaena is one of the commonly observed genera in the rice fields in South-east Asia. Diversity analyses of a set of 70 Anabaena strains (including 67 strains isolated from diverse rice agro ecologies of India, and three International Reference/Type strains), was carried out using morphological and molecular datasets. The pattern of growth in liquid and solid medium and microscopic observations revealed tremendous diversity in the Anabaena germplasm analysed. The species wise distribution in different soil types and soil pH revealed that Anabaena iyengarii was present at pH ranging from 5.5-8.5 and all the species of Anabaena except A. oscillarioides were present in alluvium soils. Molecular profiling using primers based on HipTG, STRRmod and STRR1A sequences generated specific ... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741160 Fri, 29 Aug 2008 04:00:00 +0100 1741160 http://www.medworm.com/index.php?rid=1741159&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800008 Psychrophiles are organisms that thrive in cold environments. One of the strategies for their cold adaptation is the ability to synthesize cold-adapted enzymes. These enzymes usually display higher catalytic efficiency and thermolability at lower temperatures compared to their mesophilic and thermophilic counterparts. In this work, a psychrophilic bacterium codenamed [pi]9 was selected for the cloning of the gene encoding glyceraldehyde-3-phosphate dehydrogenase (GAPDH), an enzyme in the glycolytic pathway. Here, the cloning of an 1113 bp fragment of GAPDH gene which covers the 1002 bp open reading frame by using multiple PCR steps is described. The partial sequence of this gene was PCR amplified by using degenerate primers followed by the cloning of the flanking sequences by inverse and s... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741159 Fri, 29 Aug 2008 04:00:00 +0100 1741159 http://www.medworm.com/index.php?rid=1741158&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800012 Halophilic archaea belonging to three different genera- Halobacterium, Haloarcula and Haloferax, were isolated from Kandla salt pans. The isolates had an optimum requirement of 25% NaCl for growth. Increase in organic solvent tolerance of isolates was observed at higher NaCl concentrations. Among the three isolates Halobacterium sp. SP1(1) was found to be more tolerant than Haloarcula sp. SP2(2) and Haloferax sp. SP1(2a). The extracellular protease of Halobacterium sp. SP1(1) showed higher solvent tolerance compared to the organism itself. The enzyme was highly tolerant to toluene, xylene, n-decane, n-dodecane and n-undecane, majority of which are frequently used in paints. These findings may help in understanding the mechanism of organic solvent tolerance in halophilic archaea and their a... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741158 Fri, 29 Aug 2008 04:00:00 +0100 1741158 http://www.medworm.com/index.php?rid=1741157&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800017 Whole-colony two-dimensional fractal growth patterns produced by hypovirus-infected Cryphonectria parasitica (EP155/CHV1-EP713) were measured and compared with those produced by the isogenic virus-free strain (EP155) on solid medium. We have quantified statistically significant differences in the rates of expansion and spatial dynamics of colony growth between the two strains and concluded that fractal dimension is affected by the presence of the hypovirus. Therefore, fractal dimension measurement is an effective quantitative tool for testing the effects of mycovirus infection on fungal growth parameters. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1741157 Fri, 29 Aug 2008 04:00:00 +0100 1741157 http://www.medworm.com/index.php?rid=1703393&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800043 Aspergillus nidulans is a highly potent fungus used in the production of alkaline protease. Extracellular alkaline protease was purified from A. nidulans in a two-step procedure involving ammonium sulphate precipitation and Sephadex G-100 column chromatography. The molecular mass of the enzyme was determined to be 42 kDa by SDS-PAGE. The enzyme activity was also analyzed by zymogram with gelatin. The enzyme was more stable over a wide range of pH (6-10) and the temperatures up to 50 °C. It showed optimum enzyme activity at pH 8.0 and a temperature of 35 °C. The protease enzyme was completely inhibited by the serine protease inhibitor of phenylmethylsulfonyl fluoride (PMSF). The crystallization of the purified enzyme was performed by hanging drop vapour diffusion method using PEG 6000 as ... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1703393 Thu, 14 Aug 2008 04:00:00 +0100 1703393 http://www.medworm.com/index.php?rid=1703398&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700360 Amycolatopsis sp. AB0, a copper resistant actinobacterium isolated from polluted sediments, has shown high copper specific biopsortion ability (25 mg g-1). Two approaches were used to confirm metal accumulation in growing cells of Amycolatopsis sp. AB0; we performed subcellular fractioning assays which showed that the retained copper was associated with the extra-cellular fraction (exopolymer, 40%), but mainly within the cells. Intracellular distribution of copper was: 86% in the cytosolic fraction, 11% at the cell wall and 3% associated with the ribosome/membrane fraction. Its copper bioaccumulation ability was corroborated by using silver enhanced staining of copper with the Timm's reagent technique, which has not been used to detect metal deposits in bacteria before. In addition, we con... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1703398 Wed, 13 Aug 2008 04:00:00 +0100 1703398 http://www.medworm.com/index.php?rid=1703397&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700365 The costs associated with soil salinity are potentially enormous and the effects of salinity may impact heavily on agriculture, biodiversity and the environment. As the saline areas under agriculture are increasing every year across the globe, it is of much public concern. Agricultural crops and soil microorganisms are affected with salinity. As Plant Growth Promoting Rhizobacteria (PGPR) have been reported to be contributing to the plant health, the osmotolerance mechanisms of these PGPRs are of importance. Pseudomonas fluorescens MSP-393 is a proven biocontrol agent for many of the crops grown in saline soils of coastal ecosystem. Studies revealed that the root colonization potential of the strain was not hampered with higher salinity in soil. As a means of salt tolerance, the strain de ... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1703397 Wed, 13 Aug 2008 04:00:00 +0100 1703397 http://www.medworm.com/index.php?rid=1703396&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700402 In the present study the role of different mammalian cell receptors in adherence of the coagulase positive pathogen, Staphylococcus aureus and some coagulase negative staphylococci, namely Staphylococcus epidermidis and Staphylococcus saprophyticus was investigated. Upon testing the adherence to Vero and Hep-2 cells, S. aureus isolates showed an adherence to both cell lines while S. epidermidis and S. saprophyticus isolates adhered to Vero cells only. According to the obtained results, both O-linked and N-linked mammalian cell surface glycoproteins are involved in the adherence of S. aureus isolates to Vero and Hep-2 cells, whereas only the O-linked ones serve as receptors for adherence of S. epidermidis and S. saprophyticus isolates to Vero cells. Of the O-linked glycoproteins, GAG-like r... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1703396 Wed, 13 Aug 2008 04:00:00 +0100 1703396 http://www.medworm.com/index.php?rid=1703395&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700406 The mode of action of an antimicrobial peptide produced by Bacillus sp. P45 isolated from the intestine of the Amazonian basin fish Piaractus mesopotamicus was investigated. The antimicrobial peptide was purified from culture supernatants by precipitation with ammonium sulfate and gel filtration chromatography. The peptide has an EC50 of 300 AU (activity units) ml-1 and kills all viable cells of Listeria monocytogenes with a concentration of 800 AU ml-1. A decrease in OD was observed when L. monocytogenes cultures were treated with the peptide, suggesting that cells were lysed. Transmission electron microscopy showed damage of the cell envelope and loss of protoplasmic material. The peptide P45 was bactericidal and bacteriolytic to L. monocytogenes. There is evidence that the mode of actio... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1703395 Wed, 13 Aug 2008 04:00:00 +0100 1703395 http://www.medworm.com/index.php?rid=1703394&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200800002 Three acid mine drainage (AMD) samples collected from Dabaoshan Mine (Guangdong Province, China) were studied. In addition to physicochemical analyses, the diversity and community structures of the archaeal communities in these samples were described at the genetic level by amplified ribosomal DNA restriction analysis (ARDRA). Nine different ARDRA patterns were obtained from 146 clones and were studied as operational taxonomic units (OTUs), which were re-amplified and sequenced. Sequence data and phylogenetic analysis showed that most of the clones belonged to the Thermoplasmatales, and that archaea belonging to the Sulfolobales were absent. Only 1 OTU attributed to Ferroplasma was found and was observed to be abundant in all 3 samples. Eight OTUs were related to 2 new undefined groups in ... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1703394 Wed, 13 Aug 2008 04:00:00 +0100 1703394 http://www.medworm.com/index.php?rid=1471015&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200890005 Double staining of MAP kinase mutant mycelia of Fusarium proliferatum with Evans blue (dark blue-stained died cells) and dihydrofluorescein-diacetate (green fluorescent cells accumulating reactive oxygen species) after exposition to salt stress by 4% NaCl. Due to this stressor aberrant, pearl-like, round-shaped cells were formed. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1471015 Wed, 28 May 2008 13:53:40 +0100 1471015 http://www.medworm.com/index.php?rid=1471026&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700366 Melanin produced by Hypoxylon archeri, a companion fungus of Tremella fuciformis, was purified from the submerged culture medium and designated as HM. Ultraviolet-visible and FTIR spectra of the purified HM showed significant similarities with those of the synthesized melanin derived from tyrosine. Thus, the HM melanin was identified to be derived from the precursor molecule of tyrosine or dihydroxyphenylalanine (DOPA).The antioxidant activity of HM melanin, synthetic melanin and vitamin C were compared by inhibition of the oxidation of 5-thio-2-nitrobenzoic acid (TNB) caused by hypochlorous acid (HOCl) and hydrogen peroxide (H2O2). The HM melanin is likely to be more efficient eliminating oxygen free radicals generated by H2O2 than by HOCl. At a concentration of 100 mg · l-1, the HM mela... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1471026 Wed, 28 May 2008 04:00:00 +0100 1471026 http://www.medworm.com/index.php?rid=1471025&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700352 Five strains of Agrobacterium tumefaciens were isolated and characterized from 12 different plant tumors. The susceptibility of these phytopathogens to antibiotics and to soil Streptomyces isolates was tested. Among the 90 Streptomyces isolates, only 12 were able to inhibit the growth of at least one A. tumefaciens strain. Four strains of A. tumefaciens were susceptible to streptomycin and cefotaxime. In addition, Streptomyces 404 strain was able to inhibit the growth of four strains of the Agrobacterium pathogens with an inhibition zone diameter ranged between 10 and 16 mm. The strong inhibitory effects of Streptomyces 404 strain on A. tumefaciens suggest the use of this strain as a promising agent to control crown gall disease. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1471025 Wed, 28 May 2008 04:00:00 +0100 1471025 http://www.medworm.com/index.php?rid=1471024&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700160 Forty three psychrotrophic bacteria were isolated from soil samples collected from Chandra river in sub-alpine region of western Himalaya, India. Among these, 11 isolates were found positive for lipase production at low temperature. Of 11 isolates, CR9 produced largest zone of clearance on plate assay and was able to produce lipase under wide range of pH. The isolate CR9 was identified as Acinetobacter sp. based on morphological and physiochemical characterization and 16S rRNA gene sequencing analysis. According to 16S rRNA gene sequencing data the closest phylogenetic neighbor for strain CR9 was Acinetobacter lwoffii (98.9%). The partially purified lipase from strain CR9 exhibited maximum activity at temperature 40 °C and pH optima at 8.0. Cu2+, Mo2+, Mg2+, Zn2+, phenylmethanesulfonyl fl... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1471024 Wed, 28 May 2008 04:00:00 +0100 1471024 http://www.medworm.com/index.php?rid=1471023&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700133 Continuous development of antibacterial compounds with novel modes of action (accompanied by rationalization of chemotherapeutic prescription) is the best way to address the growing problem of antibiotic-resistant infections. Numerous clinically important antibiotics interfere with peptidoglycan cell wall biosynthesis making this unique metabolic pathway a well validated target for antimicrobials. While nearly all of these antibiotics inhibit late stages of murein synthesis occurring on the extracellular side of plasma membrane, initial cytoplasmic steps have not been extensively exploited as drug targets. We performed affinity selection of peptides from phage-displayed libraries against two essential bacterial enzymes MurD and MurE involved in the cytoplasmic synthesis of peptidoglycan mo... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1471023 Wed, 28 May 2008 04:00:00 +0100 1471023 http://www.medworm.com/index.php?rid=1471022&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700324 The present study is aimed at assessing the ability of metal resistant yeast, Loddermyces elongisporus, to uptake metal from liquid medium. The minimum inhibitory concentration of Cu2+ against Loddermyces elongisporus ranged between 2.2-2.3 mg/l. The yeast could also tolerate Zn2+ (2.9 mg/l), Hg2+ (2.4 mg/l), Ni2+ (2.2 mg/l), Cr6+ (2.0 mg/l), Pb2+ (1.1 mg/l), and Cd2+ (0.8 mg/l). The yeast isolate showed typical growth curves but lag and log phases extended in the presence of copper. Yeast isolate showed optimum growth at 30 ºC and pH 8. Metal processing ability of the isolate was determined in a medium containing 0.1 mg/l of Cu2+. Loddermyces elongisporus could reduce Cu2+ 15%, 26%, 39%, 50%, 60%, 67%, 75% and 81% from the medium after 6, 12, 18, 24, 30, 48, 72 and 96 hours, respectively... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1471022 Wed, 28 May 2008 04:00:00 +0100 1471022 http://www.medworm.com/index.php?rid=1471021&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700199 This study is a first time report on the production of hydrolytic enzymes by these oxygenic photosynthetic prokaryotes, which can be potential candidates for the development of biocontrol agent(s) against selected phytopathogenic fungi. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1471021 Wed, 28 May 2008 04:00:00 +0100 1471021 http://www.medworm.com/index.php?rid=1471020&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700326 The complete nucleotide sequence of plasmid pA387 of Amycolatopsis benzoatilytica DSM 43387 was determined. Sequence analysis revealed that pA387 is 30,157 bp long and has a G+C content of 71.74%. To obtain a minimal transferable replicon capable of self-replication, a 2,176 bp fragment of pA387 was cloned, and we demonstrated that this fragment is sufficient for autonomous replication. The replication region of pA387 exhibited no significant homology to any known replication proteins available in databases. Putative maintenance and transfer functions were identified on pA387. The predicted products of open reading frames, ORF 2 and ORF 12, resembled the plasmid stabilizing proteins, a DNA resolvase and a ParA protein, respectively. The putative translational products of ORF 15 and ORF 16 ... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1471020 Wed, 28 May 2008 04:00:00 +0100 1471020 http://www.medworm.com/index.php?rid=1471019&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700338 Sixty six isolates of Pseudomonas spp. were isolated from wastewater of El-Malah canal located in Assiut, Egypt and were checked for their heavy metal tolerance. One isolate has tested for its multiple metal resistances and found to be plasmid mediated with molecular weight 27 Kb for nickel and lead. It was identified as Pseudomonas aeruginosa ASU 6a. Its minimal inhibitory concentration (MIC) for Cu2+, Co2+, Ni2+, Zn2+, Cr3+, Cd2+and Pb2+ were 6.3, 5.9, 6.8, 9.2, 5.8, 4.4, and 3.1 mM, respectively. Growth kinetics and the maximum adsorption capacities were determined under Ni2+ and Pb2+ stress. The latter heavy metals induced potassium efflux and were used as indicator for plasma membrane permeabilization. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Micr... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1471019 Wed, 28 May 2008 04:00:00 +0100 1471019 http://www.medworm.com/index.php?rid=1471018&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700361 Fifty strains of moderately halophilic bacteria were isolated from various salty environments in Iran. A strain designated as SA-2 was shown to be the best producer of extracellular lipase and was selected for further studies. Biochemical and physiological characterization along with 16S rDNA sequence analysis placed SA-2 in the genus Salinivibrio. The optimum salt, pH, temperature and aeration for enzyme production were 0.1 M KCl, pH 8, 35 °C and 150 rpm, respectively. The enzyme production was synchronized bacterial growth and reached a maximum level during the early-stationary phase in the basal medium containing 1 M NaCl. Triacylglycerols enhanced lipase production, while carbohydrates had inhibitory effects on it. The maximum lipase activity was obtained at pH 7.5, 50 °C and CaCl2 c... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1471018 Wed, 28 May 2008 04:00:00 +0100 1471018 http://www.medworm.com/index.php?rid=1471017&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700403 [Delta]Fphog1 mutants of Fusarium proliferatum obtained by targeted gene disruption of Fphog1, an orthologue of the Saccharomyces cerevisiae hog1 MAPK gene showed increased sensitivity towards different abiotic stressors including UV-irradiation, heat, salt, osmotic and hydrogen peroxide treatments. Incubation of the [Delta]Fphog1 mutants under hyperosmotic conditions was accompanied with prolonged growth arrest, inhibition of conidial germination, morphological abnormalities and time-dependent increase of the cell death rate. The wild type Fphog1 gene, under the control of its own promoter, was able to rescue the multistress sensitivity of the mutant strain. Real time qPCR data demonstrated that under salt and sorbitol stress conditions the Fphog1 gene is not subject of transcriptional re... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1471017 Wed, 28 May 2008 04:00:00 +0100 1471017 http://www.medworm.com/index.php?rid=1471016&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200890006 No Abstract (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1471016 Wed, 28 May 2008 04:00:00 +0100 1471016 http://www.medworm.com/index.php?rid=1331927&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200890003 No Abstract (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331927 Fri, 28 Mar 2008 08:15:55 +0100 1331927 http://www.medworm.com/index.php?rid=1331940&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200890002 No Abstract (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331940 Thu, 27 Mar 2008 04:00:00 +0100 1331940 http://www.medworm.com/index.php?rid=1331939&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700363 A new spiroketal, named aspergiketal (1) was isolated from the culture broth of Aspergillus terreus, an endophytic fungus in the stems of the plant Opuntia ficusindica Mill., together with two known compounds, physcion (2) and asterric acid (3). Their structures were elucidated by spectroscopic methods including 2D-NMR techniques. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331939 Thu, 27 Mar 2008 04:00:00 +0100 1331939 http://www.medworm.com/index.php?rid=1331938&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700291 Heavy metal contamination of the rivers is a world wide environmental problem and its removal is a great challenge. Kanpur and Unnao two closely located districts of Uttar Pradesh India are known for their leather industries. The tanneries release their treated effluent in the near by water ways containing Cr metal that eventually merges with the river Ganges. Untreated tannery effluent contains 2.673 ± 0.32 to 3.268 ± 0.73 mg l-1 Cr. Microbes were isolated, keeping the natural selection in the view, from the tannery effluent since microbes present in the effluent exposed to the various types of stresses and metal stress is one of them. Investigations include the exposure of higher concentrations of Cr(VI) 1.0 to 4.0 mg l-1 to the bacteria (presumably the Pseudomonas spp.) predominant on... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331938 Thu, 27 Mar 2008 04:00:00 +0100 1331938 http://www.medworm.com/index.php?rid=1331937&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700273 Pseudomonas sp. isolated from soil of coffee plantation area has been shown to degrade higher concentrations of caffeine ([sim]15 g l-1) by N-demethylation at a rate higher than what has been reported for any strain so far. This strain exhibits positive chemotaxis towards caffeine (1,3,7-trimethylxanthine) in swarm plate assay and modified capillary assay in a dose dependant manner. Related methylxanthines and xanthine also act as chemoattractants for the strain with the highest relative chemotactic response (RCR) seen for xanthine. Chemotaxis in Pseudomonas sp. is possibly plasmid mediated as indicated by positive chemotaxis of plasmid transformed E. coli DH5[alpha]. The chemotactic abilities of Pseudomonas sp. combined with higher rates of degradation of caffeine can be used in the devel... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331937 Thu, 27 Mar 2008 04:00:00 +0100 1331937 http://www.medworm.com/index.php?rid=1331936&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700302 Nutrient enrichment with a nitrogen (as nitrate) or carbon (as fructose) source to unaerated diazo and photoautorophic cultures of the cyanobacterium Anabaena torulosa induced early development of akinetes with high frequency. When cultures under any mode of nutrition were aerated, akinetes were not differentiated. Unaerated cultures with nitrate nitrogen or fructose exhibited higher respiratory rates and nitrogen assimilation compared to aerated cultures. This was evidenced by increased respiratory O2 uptake and high activities of pyruvate kinase, malate dehydrogenase (NAD+), nitrogenase and nitrate reductase signifying that akinete forming unaerated cultures exhibited high carbon dissimilation and nitrogen assimilation resulting in high nitrogenous build up in the cells. Aerated, non-aki... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331936 Thu, 27 Mar 2008 04:00:00 +0100 1331936 http://www.medworm.com/index.php?rid=1331935&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700161 The genetic diversity of 29 endophytic bacterial strains isolated from apoplastic sap of the medullary parenchym of the stem of healthy sugarcane plants grown in Cuba was analysed by Two Primers-Ramdom Amplified Polymorphic DNA fingerprinting (TP-RAPD) and 16S rRNA gene sequencing. The strains were distributed into 17 groups on the basis of their TP-RAPD patterns, and a representative strain from each group was subjected to 16S rRNA gene sequencing. Analysis of these sequences showed that the isolates belong to a wide variety of phylogenetic groups being closely related to species of genera Bacillus and Staphylococcus from Firmicutes, Microbacterium, Micrococcus and Kokuria from Actinobacteria, Rhizobium and Gluconacetobacter from [alpha] -Proteobacteria, Comamonas and Xanthomonas from [be... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331935 Thu, 27 Mar 2008 04:00:00 +0100 1331935 http://www.medworm.com/index.php?rid=1331934&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700314 Ten species of Aspergillus were screened for occurrence of lectins. Each of the species was investigated for the occurrence of extracellular, surface-bound and intracellular lectin activities. As many as four species namely, Aspergillus niger, Aspergillus versicolor, Aspergillus rugulosus and Aspergillus nidulans, were found to possess intracellular lectin activities, while none of the species showed extracellular or surface-bound lectin activities. Each of the lectin was characterized with respect to blood group and carbohydrate specificities. All the lectins were found to agglutinate human erythrocytes, irrespective of their blood group and pig erythrocytes. However, they did not show agglutination with sheep or goat erythrocytes. Of the various carbohydrates tested, all lectins were fou... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331934 Thu, 27 Mar 2008 04:00:00 +0100 1331934 http://www.medworm.com/index.php?rid=1331933&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700262 Effect of iron and chelator on the growth and siderophore production in the ten newly Frankia strains isolated from the root nodules of Hippophae salicifolia D. Don and the two reference strains were studied. Growth of the strains was greatly affected when grown in the iron and EDTA deprived conditions. All the strains were capable of producing both the hydroxamate and catecholate type siderophore that was detected using the Csaky and Arnow assays. Production of siderophore was enhanced in the EDTA replenish condition in contrast to the iron supplemented medium suggesting that EDTA reduces the availability of other free metals and hence creates the stress condition for which the secretion of siderophore is enhanced. A decrease in siderophore production was observed with an increase in iron... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331933 Thu, 27 Mar 2008 04:00:00 +0100 1331933 http://www.medworm.com/index.php?rid=1331932&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700292 Farnesol was the first quorum-sensing regulator to be found in eukaryotic cells. In Candida albicans, a dimorphic fungal human pathogen, farnesol blocks the yeast-to-filamentous growth transition. Here we show that in Aspergillus niger farnesol acts as an inhibitor of conidiation: Colonies grown on media containing farnesol were unable to develop conidia. Although farnesol treated A. niger cultures exhibited a colony morphology resembling the "fluffy" phenotype of A. nidulans, which is caused by a hyperactive G-protein/cAMP pathway, the intracellular level of cAMP in A. niger mycelia grown in presence of farnesol is greatly diminished. Furthermore, whereas inhibiting adenylyl cyclase led to a farnesol-like effect, the addition of external cAMP inhibited conidiation without causing a "fluff... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331932 Thu, 27 Mar 2008 04:00:00 +0100 1331932 http://www.medworm.com/index.php?rid=1331931&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700257 In this study, which is the first on the intraspecific variability of a large set of R. mucilaginosa isolates, a considerable phenotypic and genetic heterogeneity was observed, however such differences were not enough to refute co-specificity. The study of Patagonian isolates allowed the detection of a genetically distinct group of R. mucilaginosa strains. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331931 Thu, 27 Mar 2008 04:00:00 +0100 1331931 http://www.medworm.com/index.php?rid=1331930&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700107 Hyoscyamus muticus L. (Egyptian henbane) is one of the desert medicinal plants of family Solanaceae. The plant produces pharmaceutically important compounds (tropane alkaloids) as secondary metabolites. In the present study, we describe mycoflora of H. muticus grown in four different locations in Egyptian southern desert (Aswan region): Aswan university campus, Wadi Allaqi down stream part, Aswan airport road, and Sahari city. Eighty-one species and two varieties belonging to 31 genera were isolated from soils surrounding H. muticus plants, the surface of the plants, and inside the plants as endophytic fungi. Aspergillus was the most common genus in all study areas. The highest number of genera and species of fungi were recorded in Aswan university campus followed by Aswan airport road. Fu... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331930 Thu, 27 Mar 2008 04:00:00 +0100 1331930 http://www.medworm.com/index.php?rid=1331929&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700350 Pseudomonas jessenii isolate EC-S101, an antagonistic rhizobacterium, induces morphological abnormalities such as topical swelling and excessive lateral branching in phytopathogenic Peronosporomycetes Pythium aphanidermatum hyphae as a result of radial growth inhibition in a dual culture assay. Rhodamine-phalloidin staining revealed that these abnormalities were associated with disorganization of actin cytoskeleton. Both the morphological forms of actin, filaments and plaques, were affected progressively. At early stage of interaction (in less affected hyphae), the filaments were either eliminated or disarrayed. At advance stage of interaction (in severely affected hyphae), even the plaques population was decreased or disappeared. The effects of P. jessenii on actin architecture of Py. aph... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331929 Thu, 27 Mar 2008 04:00:00 +0100 1331929 http://www.medworm.com/index.php?rid=1331928&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200890004 No Abstract (Source: Journal of Basic Microbiology) Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1331928 Thu, 27 Mar 2008 04:00:00 +0100 1331928 http://www.medworm.com/index.php?rid=1199128&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700294 The production of the polysaccharide curdlan from the ethanol processing coproduct condensed corn distillers solubles by the bacterium Agrobacterium sp. ATCC 31749 was investigated. It was found that curdlan could be produced by the bacterium using condensed corn distillers solubles as a source of carbon and nitrogen. As the concentration of condensed corn distillers solubles was increased from 50 g l-1 to 400 g l-1, the concentration of curdlan increased but not proportionally. The highest curdlan concentration was produced by the strain on 400 g l-1 condensed corn distillers solubles after 120 h and its level was higher than was observed for glucose-based curdlan production. Biomass production by ATCC 31749 was also highest after 120 h of growth on 400 g l-1 condensed corn distillers sol... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1199128 Mon, 04 Feb 2008 05:00:00 +0100 1199128 http://www.medworm.com/index.php?rid=1199127&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700221 The Agrobacterium -mediated transformation was adapted to Backusella lamprospora, a zygomycete fungus closely related to Mucor. The transforming plasmid contained the hygromycin B resistance (hph) and the green fluorescent protein (gfp) genes under the control of the regulator regions of the Mucor circinelloides gpd1 gene. The presence of the hph and gfp genes in the transformants was detected by PCR. The introduced genes could also be amplified directly from the spores of the transformants. The transformation efficiency was investigated by fluorescence microscopy of the transformed spores. A gradual decrease in the hygromycin B resistance was observed during several cultivation cycles: the growth of the transformants on the selection medium became slower, and the detection of the introduc... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1199127 Mon, 04 Feb 2008 05:00:00 +0100 1199127 http://www.medworm.com/index.php?rid=1199126&cid=s_33775_77_f&fid=33775&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fjobm.200700116 Effect of production medium components, initial starch and soyabean meal concentrations, for the enhanced production of gentamicin by Micromonospora echinospora (Me- 22) was studied in a lab scale stirred tank reactor. Also effect of different aeration (0.5, 1, 2, and 4 vvm) and agitation rates (100, 200, 300 and 400 rpm) in a stirred tank reactor was examined. A maximum gentamicin concentration of 2.68 g l-1 was achieved in the medium having low concentrations of initial starch (7.5 g l-1) and high concentrations of initial soyabean meal (4 g l-1). Both aeration and agitation significantly affected gentamicin concentration, productivity and biomass formation. The maximum gentamicin concentration of 4.12 g l-1 and the highest yield of gentamicin on substrate 0.967 g g-1 were obtained at im... Journal of Basic Microbiology journals http://www.medworm.com/rss/comments.php?id=1199126 Mon, 04 Feb 2008 05:00:00 +0100 1199126