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This page shows you the most recent publications within this specialty of the MedWorm directory. This is page number 36.
Effects of thermosonication on the fate of Escherichia coli O157:H7 and Salmonella Enteritidis in mango juice
In this study, the effects of thermosonication and thermal treatment on Escherichia coli O157:H7 and Salmonella Enteritidis in mango juice were investigated at 50 and 60 °C. Besides, non‐lethal injury of S. Enteritidis after both treatments was also examined. The highest inactivation was attained with thermosonication at 60 °C. The inactivation rate was different for both pathogens and S. Enteritidis was found to be more sensitive to thermosonication than E. coli O157:H7. S. Enteritidis was recovered in all treated samples, except those subjected to more than five minutes thermosonication at 60 °C. It was found that t...
Source: Letters in Applied Microbiology - December 26, 2012 Category: Microbiology Authors: Wei‐Seng Kiang, Rajeev Bhat, Ahmad Rosma, Lai‐Hoong Cheng Tags: Original Article Source Type: research
Benzamidine derivatives inhibit the virulence of Porphyromonas gingivalis
Summary We have previously shown that benzamidine‐type compounds can inhibit the activity of arginine‐specific cysteine proteinases (gingipains HRgpA and RgpB); well‐known virulence factors of Porphyromonas gingivalis. They also hinder in vitro growth of this important periodontopathogenic bacterium. Apparently growth arrest is not associated with their ability to inhibit these proteases, because pentamidine, which is a 20‐fold less efficient inhibitor of gingipain than 2,6‐bis‐(4‐amidinobenzyl)‐cyclohexanone (ACH), blocked P. gingivalis growth far more effectively. To identify targets for benzamidine‐de...
Source: Oral Microbiology and Immunology - December 26, 2012 Category: Microbiology Authors: E. Fröhlich, T. Kantyka, K. Plaza, K.‐H. Schmidt, W. Pfister, J. Potempa, S. Eick Tags: Original Article Source Type: research
Chest computed tomography predicts microbiological burden and symptoms in pulmonary Mycobacterium xenopi
Conclusions: Among immunocompetent patients with pulmonary M. xenopi isolation, cavitation and large nodules predict fulfilling microbiological disease criteria, while bronchiectasis and small nodules predict symptoms.
Source: Respirology - December 26, 2012 Category: Respiratory Medicine Authors: THEODORE K. MARRAS, UTE WAGNETZ, FRANCES B. JAMIESON, DEMETRIS A. PATSIOS Tags: ORIGINAL ARTICLE Source Type: research
The physicochemical and microbiological quality of the Sudanese yoghurt Mish produced by traditional and modernised methods
The traditional and modernised processing of Mish were assessed by comparing samples from modernised process with the traditional process: in each case, six batches were evaluated, with six samples per batch. The results indicated highly significant (P ≤ 0.001) differences in protein, ash and fat content, the viscosity and all microbiological parameters tested between the traditional and modern produced Mish. However, the storage period showed significant variations only for the microbiological parameters, as some contaminants were found for samples processed by the traditional procedure. Hence, the study recommended t...
Source: International Journal of Dairy Technology - December 26, 2012 Category: Nutrition Authors: Mustafa K H Abdel‐Gader, Jafar M El‐bakri, Ibtisam E M El Zubeir Tags: Original Research Source Type: research
Cloning and recombinant expression of a cellulase from the cellulolytic strain Streptomyces sp. G12 isolated from compost
Conclusions: In this manuscript we describe the isolation of a new cellulolytic strain, Streptomyces sp. G12, from industrial waste based compost, the identification of the enzymes putatively responsible for its cellulolytic activity, the cloning and the recombinant expression of the gene coding for the Streptomyces sp. G12 cellulase CelStrep, that was characterized showing to exhibit a relevant thermoresistance increasing its potential for cellulose conversion.
Source: Microbial Cell Factories - December 26, 2012 Category: Microbiology Authors: Antonella AmoreOlimpia PepeValeria VentorinoLeila BiroloChiara GiangrandeVincenza Faraco Source Type: research
Neisseria gonorrhoeae Breaches the Apical Junction of Polarized Epithelial Cells for Transmigration by activating EGFR
This study examines the interaction of gonococci (GC) with polarized epithelial cells. We show that viable GC preferentially localize at the apical side of the cell‐cell junction in polarized endometrial and colonic epithelial cells, HEC‐1‐B and T84. In GC infected cells, continuous apical junctional complexes are disrupted, and the junction‐associated protein β‐catenin is redistributed from the apical junction to the cytoplasm and to GC adherent sites, however overall cellular levels remain unchanged. This redistribution of junctional proteins is associated with a decrease in the ‘fence’ function of the api...
Source: Cellular Microbiology - December 26, 2012 Category: Microbiology Authors: Vonetta L. Edwards, Liang‐Chun Wang, Valerie Dawson, Daniel C. Stein, Wenxia Song Tags: Research Article Source Type: research
Type III secretion translocon assemblies that attenuate Yersinia virulence
Summary Type III secretion enables bacteria to intoxicate eukaryotic cells with anti‐host effectors. A class of secreted cargo are the two hydrophobic translocators that form a translocon pore in the host cell plasma membrane through which the translocated effectors may gain cellular entry. In pathogenic Yersinia, YopB and YopD shape this translocon pore. Here, four in cis yopD mutations were constructed to disrupt a predicted α‐helix motif at the C‐terminus. Mutants YopDI262P and YopDK267P poorly localised Yop effectors into target eukaryotic cells and failed to resist uptake and killing by immune cells. These defe...
Source: Cellular Microbiology - December 26, 2012 Category: Microbiology Authors: Tiago R. D. Costa, Ayad A. A. Amer, Salah I. Farag, Hans Wolf‐Watz, Maria Fällman, Anna Fahlgren, Tomas Edgren, Matthew S. Francis Tags: Research Article Source Type: research
Hemoglobin S and C affect the motion of Maurer's clefts in P. falciparum‐infected erythrocytes
Summary The hemoglobinopathies S and C protect carriers from severe Plasmodium falciparum malaria. We have recently shown that hemoglobin S and C interfere with host‐actin remodeling in parasitized erythrocytes and the generation of an actin network that seems to be required for vesicular protein trafficking from the Maurer's clefts (a parasite‐derived intermediary protein secretory organelle) to the erythrocyte surface. Here we show that the actin network exerts skeletal functions by anchoring the Maurer's clefts within the erythrocyte cytoplasm. Using a customized tracking tool to investigate the motion of single Mau...
Source: Cellular Microbiology - December 26, 2012 Category: Microbiology Authors: Nicole Kilian, Martin Dittmer, Marek Cyrklaff, Djeneba Ouermi, Cyrille Bisseye, Jacques Simpore, Friedrich Frischknecht, Cecilia P. Sanchez, Michael Lanzer Tags: Research Article Source Type: research
The Role of Galectin‐3 in Phagocytosis of Candida albicans and Candida parapsilosis by Human Neutrophils
This study investigates the human neutrophil phagocytic response to these species. Neutrophils underwent phagocytosis of C. parapsilosis yeast and C. albicans hyphae much more efficiently than C. albicans yeast. Treatment of neutrophils with a galectin‐3 (gal3) blocking antibody inhibited phagocytosis of C. parapsilosis yeast and C. albicans hyphae, but not C. albicans yeast. The majority of neutrophil gal3 was expressed intracellularly and was secreted from neutrophils after treatment with C. parapsilosis mannan. When neutrophils were treated with exogenous gal3, phagocytosis of both C. albicans and C. parapsilosis yeas...
Source: Cellular Microbiology - December 26, 2012 Category: Microbiology Authors: Jennifer R. Linden, Dennis Kunkel, Sonia S. Laforce‐Nesbitt, Joseph M. Bliss Tags: Research Article Source Type: research
The group A streptococcal collagen‐like protein‐1, Scl1, mediates biofilm formation by targeting the extra domain A‐containing variant of cellular fibronectin expressed in wounded tissue
Summary Wounds are known to serve as portals of entry for group A Streptococcus (GAS). Subsequent tissue colonization is mediated by interactions between GAS surface proteins and host extracellular matrix components. We recently reported that the streptococcal collagen‐like protein‐1, Scl1, selectively binds the cellular form of fibronectin (cFn) and also contributes to GAS biofilm formation on abiotic surfaces. One structural feature of cFn, which is predominantly expressed in response to tissue injury, is the presence of a spliced variant containing extra domain A (EDA/EIIIA). We now report that GAS biofilm formation...
Source: Molecular Microbiology - December 26, 2012 Category: Microbiology Authors: Heaven Oliver‐Kozup, Karen H. Martin, Diane Schwegler‐Berry, Brett J. Green, Courtney Betts, Arti V. Shinde, Livingston Van De Water, Slawomir Lukomski Tags: Research Article Source Type: research
Free radical scavenging capacity, anticandicidal effect of bioactive compounds from Sida Cordifolia L., in combination with nystatin and clotrimazole and their effect on specific immune response in rats
Conclusion: The results of this study showed that alkaloid compounds in combination with antifungal references (Nystatin and Clotrimazole) exhibited antimicrobial effects against candida strains tested.The results supported the utilization of these plants in infectious diseases particularly in treatment of candida infections.
Source: Annals of Clinical Microbiology and Antimicrobials - December 26, 2012 Category: Microbiology Authors: Maurice OuédraogoKiessoun KonatéAlexis LepenguéAlain SouzaBertrand M¿BatchiLaya Sawadogo Source Type: research
SPP inhibition as antiparasitic target [Microbiology]
Early secretory and endoplasmic reticulum (ER)-localized proteins that are terminally misfolded or misassembled are degraded by a ubiquitin- and proteasome-mediated process known as ER-associated degradation (ERAD). Protozoan pathogens, including the causative agents of malaria, toxoplasmosis, trypanosomiasis, and leishmaniasis, contain a minimal ERAD network relative to higher eukaryotic cells, and, because...
Source: Proceedings of the National Academy of Sciences - December 26, 2012 Category: Science Authors: Harbut, M. B., Patel, B. A., Yeung, B. K. S., McNamara, C. W., Bright, A. T., Ballard, J., Supek, F., Golde, T. E., Winzeler, E. A., Diagana, T. T., Greenbaum, D. C. Tags: Biological Sciences Source Type: research
Structural basis of toxicity and immunity in CDI [Microbiology]
We present crystal structures of CDI toxin/immunity complexes from Escherichia coli EC869 and Burkholderia pseudomallei 1026b. Despite sharing little sequence identity, the toxin domains are structurally similar and have homology to endonucleases. The EC869...
Source: Proceedings of the National Academy of Sciences - December 26, 2012 Category: Science Authors: Morse, R. P., Nikolakakis, K. C., Willett, J. L. E., Gerrick, E., Low, D. A., Hayes, C. S., Goulding, C. W. Tags: Biological Sciences Source Type: research
Receptor binding of influenza hemagglutinin [Microbiology]
The hemagglutinin (HA) of influenza A(H3N2) virus responsible for the 1968 influenza pandemic derived from an avian virus. On introduction into humans, its receptor binding properties had changed from a preference for avian receptors (α2,3-linked sialic acid) to a preference for human receptors (α2,6-linked sialic acid). By 2001, the avidity...
Source: Proceedings of the National Academy of Sciences - December 26, 2012 Category: Science Authors: Lin, Y. P., Xiong, X., Wharton, S. A., Martin, S. R., Coombs, P. J., Vachieri, S. G., Christodoulou, E., Walker, P. A., Liu, J., Skehel, J. J., Gamblin, S. J., Hay, A. J., Daniels, R. S., McCauley, J. W. Tags: Biological Sciences Source Type: research
Mutually exclusive expressions in P. falciparum [Microbiology]
Plasmodium falciparum causes the deadliest form of human malaria. Its virulence is attributed to its ability to modify the infected RBC and to evade human immune attack through antigenic variation. Antigenic variation is achieved through tight regulation of antigenic switches between variable surface antigens named “P. falciparum erythrocyte membrane protein-1”...
Source: Proceedings of the National Academy of Sciences - December 26, 2012 Category: Science Authors: Avraham, I., Schreier, J., Dzikowski, R. Tags: PNAS Plus Source Type: research
Additional risk factors for infection by multidrug-resistant pathogens in healthcare-associated infection: a large cohort study
Background: There is a lack of consensus regarding the definition of risk factors for healthcare-associated infection (HCAI). The purpose of this study was to identify additional risk factors for HCAI, which are not included in the current definition of HCAI, associated with infection by multidrug-resistant (MDR) pathogens, in all hospitalized infected patients from the community. Methods: This 1-year prospective cohort study included all patients with infection admitted to a large, tertiary care, university hospital. Risk factors not included in the HCAI definition, and independently associated with MDR pathogen infection...
Source: BMC Infectious Diseases - December 26, 2012 Category: Infectious Diseases Authors: Teresa CardosoOrquídea RibeiroIrene AragãoAltamiro Costa-PereiraAntónio Sarmento Source Type: research
Scientists sequence genome of pathogen responsible for pneumocystis pneumonia
(American Society for Microbiology) Scientists have sequenced the genome of the fungus Pneumocystis jirovecii, an advancement that could help identify new targets for drugs to treat and prevent Pneumocystis pneumonia, a common and often deadly infection in immunocompromised patients.
Source: EurekAlert! - Medicine and Health - December 26, 2012 Category: Global & Universal Source Type: news
Comparative lipidomics analysis of HIV‐1 particles and their producer cell membrane in different cell lines
Summary Human immunodeficiency virus type 1 (HIV‐1) is a retrovirus that obtains its lipid envelope by budding through the plasma membrane of infected host cells. Various studies indicated that the HIV‐1 membrane differs from the producer cell plasma membrane suggesting virus budding from pre‐existing subdomains or virus‐mediated induction of a specialised budding membrane. To perform a comparative lipidomics analysis by quantitative mass spectrometry, we first evaluated two independent methods to isolate the cellular plasma membrane. Subsequent lipid analysis of plasma membranes and HIV‐1 purified from two diffe...
Source: Cellular Microbiology - December 25, 2012 Category: Microbiology Authors: Maier Lorizate, Timo Sachsenheimer, Bärbel Glass, Anja Habermann, Mathias J. Gerl, Hans‐Georg Kräusslich, Britta Brügger Tags: Research Article Source Type: research
The 2‐methylcitrate cycle is implicated in the detoxification of propionate in Toxoplasma gondii
Summary Toxoplasma gondii belongs to the coccidian‐subgroup of the Apicomplexa phylum. The Coccidia are obligate intracellular pathogens that establish infection in their mammalian host via the enteric route. These parasites lack a mitochondrial pyruvate dehydrogenase complex but have preserved the degradation of branched‐chain amino acids (BCAA) as a possible pathway to generate acetyl‐CoA. Importantly, degradation of leucine, isoleucine and valine could lead to concomitant accumulation of propionyl‐CoA, a toxic metabolite that inhibits cell growth. Like fungi and bacteria, the Coccidia possess the complete set of...
Source: Molecular Microbiology - December 25, 2012 Category: Microbiology Authors: Julien Limenitakis, Rebecca D. Oppenheim, Darren J. Creek, Bernardo J. Foth, Michael P. Barrett, Dominique Soldati‐Favre Tags: Research Article Source Type: research
Holidaymakers at risk as doctors run out of typhoid vaccine
Supply crisis sparked by manufacturer's recall – 700,000 people already injected could be affectedTravellers jetting off to exotic climes this winter face a scramble to get immunised against typhoid, because of a UK shortage of vaccine against the potentially fatal disease.Immunisation against typhoid fever is usually provided free of charge on the NHS but many GP surgeries across the country say they have run out. A number of travel clinics, which charge for vaccinations, are in the same situation.The shortage is the knock-on effect of a recall in October by Sanofi Pasteur MSD of 16 batches of its injectable typhoid vac...
Source: Guardian Unlimited Science - December 25, 2012 Category: Science Authors: Haroon Siddique Tags: Infectious diseases Pharmaceuticals industry News guardian.co.uk Medical research Microbiology Travel UK news Medical advice for travellers Business Science Source Type: news
Pigs In Southern China Infected With Avian Flu
Researchers report for the first time the seroprevalence of three strains of avian influenza viruses in pigs in southern China, but not the H5N1 avian influenza virus. Their research, published online ahead of print in the Journal of Clinical Microbiology, has implications for efforts to protect the public health from pandemics. Influenza A virus is responsible both for pandemics that have killed millions worldwide, and for the much less severe annual outbreaks of influenza...
Source: Health News from Medical News Today - December 25, 2012 Category: Consumer Health News Tags: Bird Flu / Avian Flu Source Type: news
Host Cholesterol Secretion Likely To Influence Gut Microbiota
For more than half a century, researchers have known that the bacteria that colonize the gastrointestinal tract of mammals influence their host's cholesterol metabolism. Now, Jens Walter and colleagues of the University of Nebraska show that changes in cholesterol metabolism induced by diet can alter the gut flora. The research was published online ahead of print in the journal Applied and Environmental Microbiology. In the study, the researchers added plant sterol esters to the diets of hamsters...
Source: Health News from Medical News Today - December 25, 2012 Category: Consumer Health News Tags: Cholesterol Source Type: news
Influence of bacterial interactions on pneumococcal colonization of the nasopharynx.
Abstract Streptococcus pneumoniae (the pneumococcus) is a common commensal inhabitant of the nasopharynx and a frequent etiologic agent in serious diseases such as pneumonia, otitis media, bacteremia, and meningitis. Multiple pneumococcal strains can colonize the nasopharynx, which is also home to many other bacterial species. Intraspecies and interspecies interactions influence pneumococcal carriage in important ways. Co-colonization by two or more pneumococcal strains has implications for vaccine serotype replacement, carriage detection, and pneumonia diagnostics. Interactions between the pneumococcus and other b...
Source: Trends in Microbiology - December 25, 2012 Category: Microbiology Authors: Shak JR, Vidal JE, Klugman KP Tags: Trends Microbiol Source Type: research
AmpG is required for the BlaXc beta‐lactamase Expression in Xanthomonas campestris pv. campestris str.17
Abstract The chromosomal ampRXc‐blaXc module is essential for the β‐lactams resistance of Xanthomonas campestris pv. campestris. BlaXc β‐lactamase is expressed at a high basal level in the absence of an inducer and its expression can be further induced by β‐lactam. In enterobacteria, ampG encodes an inner membrane facilitator involved in the recycling of murein degradation compounds. Isogenic ampG mutant (XcampG) of X. campestris pv. campestris str.17 (Xc17) was constructed to investigate the link between murein recycling and blaXc expression. Our data demonstrated that 1) XcampG is susceptible to β‐lactam an...
Source: FEMS Microbiology Letters - December 24, 2012 Category: Microbiology Authors: Tsuey‐Ching Yang, Tzu‐Fan Chen, Jeffrey J. P. Tsai, Rouh‐Mei Hu Tags: Research Letter Source Type: research
Molecular mechanisms of Escherichia coli pathogenicity
Nature Reviews Microbiology 11, 141 (2013). doi:10.1038/nrmicro2953 Author: Matthew A. Croxen & B. Brett Finlay Nature Reviews Microbiology8, 26–38 (2010)On page 31 of this article, in the third paragraph of the section 'Enterotoxic Escherichia coli', the sentence “This leads to increased intracellular levels of cyclic GMP and activates the cystic
Source: Nature Reviews Microbiology - December 24, 2012 Category: Microbiology Authors: Matthew A. CroxenB. Brett Finlay Tags: Corrigendum Source Type: research
Bacteriocins — a viable alternative to antibiotics?
Nature Reviews Microbiology 11, 95 (2013). doi:10.1038/nrmicro2937 Authors: Paul D. Cotter, R. Paul Ross & Colin Hill Solutions are urgently required for the growing number of infections caused by antibiotic-resistant bacteria. Bacteriocins, which are antimicrobial peptides produced by certain bacteria, might warrant serious consideration as alternatives to traditional antibiotics. These molecules exhibit significant potency against other bacteria (including antibiotic-resistant strains), are stable
Source: Nature Reviews Microbiology - December 24, 2012 Category: Microbiology Authors: Paul D. CotterR. Paul RossColin Hill Tags: Review Source Type: research
The excludon: a new concept in bacterial antisense RNA-mediated gene regulation
Nature Reviews Microbiology 11, 75 (2013). doi:10.1038/nrmicro2934 Authors: Nina Sesto, Omri Wurtzel, Cristel Archambaud, Rotem Sorek & Pascale Cossart In recent years, non-coding RNAs have emerged as key regulators of gene expression. Among these RNAs, the antisense RNAs (asRNAs) are particularly abundant, but in most cases the function and mechanism of action for a particular asRNA remains elusive. Here, we highlight a recently discovered
Source: Nature Reviews Microbiology - December 24, 2012 Category: Microbiology Authors: Nina SestoOmri WurtzelCristel ArchambaudRotem SorekPascale Cossart Tags: Progress Source Type: research
Viral evolution: It takes two genomes
Nature Reviews Microbiology 11, 70 (2013). doi:10.1038/nrmicro2952 Author: Christina Tobin Kåhrström Experimental evolution of measles virus reveals that a new phenotype emerges through cooperation between two different viral genomes in a single virion.
Source: Nature Reviews Microbiology - December 24, 2012 Category: Microbiology Authors: Christina Tobin Kåhrström Tags: Research Highlight Source Type: research
Assessment of cagE and babA mRNA Expression During Morphological Conversion of Helicobacter pylori From Spiral to Coccoid.
Abstract Helicobacter pylori (H. Pylori) is an actively dividing spiral bacterium that changes to coccoid morphology under stressful environments. The infectivity of the coccoids is still controversial. The aim of this study was to determine the viability and expression of two important virulence genes (babA and cagE), in antibiotic-induced coccoid forms. Three strains of H. pylori, the standard 26695 and two clinical isolates (p1, p2) were converted to coccoid form by amoxicillin. Coccoids were identified according to Gram-staining and microscopic morphology. The viability of the cells was analyzed by flow cytomet...
Source: Current Microbiology - December 24, 2012 Category: Microbiology Authors: Poursina F, Faghri J, Moghim S, Zarkesh-Esfahani H, Nasr-Esfahani B, Fazeli H, Hasanzadeh A, Safaei HG Tags: Curr Microbiol Source Type: research
Fusobacterium nucleatum subsp. fusiforme Gharbia and Shah 1992 is a Later Synonym of Fusobacterium nucleatum subsp. vincentii Dzink et al. 1990.
Abstract On the basis of the DNA-DNA hybridization patterns and phenotypic characteristics, Fusobacterium nucleatum was classified into five subspecies. Previous studies have suggested that F. nucleatum subsp. vincentii is genetically similar to F. nucleatum subsp. fusiforme. The aim of this study was to investigate the possibility of classifying these two subspecies into a single subspecies by phylogenetic analysis using a single sequence (24,715 bp) concatenated 22 housekeeping genes of eight F. nucleatum strains including type strains of five F. nucleatum subspecies. The phylogenetic analysis indicated that F. ...
Source: Current Microbiology - December 24, 2012 Category: Microbiology Authors: Kook JK, Park SN, Lim YK, Choi MH, Cho E, Kong SW, Shin Y, Paek J, Chang YH Tags: Curr Microbiol Source Type: research
In Vitro Comparative Evaluation of the Impact of Lacto-N-Biose I, a Major Building Block of Human Milk Oligosaccharides, on the Fecal Microbiota of Infants.
In conclusion, LNB might have a beneficial effect on the fecal microbiota of infants and is a potential prebiotic for application in infant foods or supplements. PMID: 23270920 [PubMed - as supplied by publisher]
Source: Anaerobe - December 24, 2012 Category: Microbiology Authors: Satoh T, Odamaki T, Namura M, Shimizu T, Iwatsuki K, Nishimoto M, Kitaoka M, Xiao JZ Tags: Anaerobe Source Type: research
Intravital two‐photon microscopy of host–pathogen interactions in a mouse model of Staphylococcus aureus skin abscess formation
Summary Staphylococcus (S.) aureus is a frequent cause of severe skin infections. The ability to control the infection is largely dependent on the rapid recruitment of neutrophils (PMN). To gain more insight into the dynamics of PMN migration and host–pathogen interactions in vivo, we used intravital two‐photon (2‐P) microscopy to visualize S. aureus skin infections in the mouse. Reporter S. aureus strains expressing fluorescent proteins were developed, which allowed for detection of the bacteria in vivo. By employing LysM‐EGFP mice to visualize PMN, we observed the rapid appearance of PMN in the extravascular ...
Source: Cellular Microbiology - December 24, 2012 Category: Microbiology Authors: Jan Liese, Suzan H. M. Rooijakkers, Jos A. G. Strijp, Richard P. Novick, Michael L. Dustin Tags: Research Article Source Type: research
Virulent Coxiella burnetii Pathotypes Productively Infect Primary Human Alveolar Macrophages
Summary The intracellular bacterial pathogen Coxiella burnetii is a Tier 2 select agent that causes human Q fever. In vivo, C. burnetii targets alveolar macrophages wherein the pathogen replicates in a lysosome‐like parasitophorous vacuole (PV). In vitro, C. burnetii infects a variety of cultured cell lines that have collectively been used to model the pathogen's infectious cycle. However, differences in the cellular response to infection have been observed, and virulent C. burnetii isolate infection of host cells has not been well defined. Because alveolar macrophages are routinely implicated in disease, we established ...
Source: Cellular Microbiology - December 24, 2012 Category: Microbiology Authors: Joseph G. Graham, Laura J. MacDonald, S. Kauser Hussain, Uma M. Sharma, Richard C. Kurten, Daniel E. Voth Tags: Research Article Source Type: research
Iron regulated surface determinant B (IsdB) promotes Staphylococcus aureus adherence to and internalization by non‐phagocytic human cells.
Summary Staphylococcus aureus is a human pathogen that causes invasive and recurring infections. The ability to internalize into and persist within host cells is thought to contribute to infection. Here we report a novel role for the well characterized iron regulated surface determinant B (IsdB) protein which we have shown can promote adhesion of 293T, HeLa cells and platelets to immobilized bacteria independently of its ability to bind haemoglobin. IsdB bound to the active form of the platelet integrin αIIbβ3, both on platelets and when the integrin was expressed ectopically in CHO cells. IsdB also promoted bacterial in...
Source: Cellular Microbiology - December 24, 2012 Category: Microbiology Authors: Marta Zapotoczna, Zala Jevnikar‐Rojnik, Helen Miajlovic, Janko Kos, Timothy J. Foster Tags: Research Article Source Type: research
The microtubule motor protein KIF13A is involved in intracellular trafficking of the Lassa virus matrix protein Z
Summary The small matrix protein Z of arenaviruses has been identified as the main driving force to promote viral particle production at the plasma membrane. Although multiple functions of Z in the arenaviral life cycle have been uncovered, the mechanism of intracellular transport of Z to the site of virus budding is poorly understood and cellular motor proteins that mediate Z trafficking remain to be identified. In the present study, we report that the Z protein of the Old World arenavirus Lassa virus (LASV) interacts with the kinesin family member 13A (KIF13A), a plus end‐directed microtubule‐dependent motor protein....
Source: Cellular Microbiology - December 24, 2012 Category: Microbiology Authors: Sarah Katharina Fehling, Takeshi Noda, Andrea Maisner, Boris Lamp, Karl‐Klaus Conzelmann, Yoshihiro Kawaoka, Hans‐Dieter Klenk, Wolfgang Garten, Thomas Strecker Tags: Research Article Source Type: research
Amazon deforestation brings loss of microbial communities
(University of Massachusetts at Amherst) An international team of microbiologists led by Klaus Nüsslein of the University of Massachusetts Amherst has found that a troubling net loss in diversity among the microbial organisms responsible for a functioning ecosystem is accompanying deforestation in the Amazon rainforest. This is important because the combination of lost forest species and the homogenization of pasture communities together signal that this ecosystem is now a lot less capable of dealing with additional outside stress.
Source: EurekAlert! - Biology - December 24, 2012 Category: Biology Source Type: news
Deforestation in the Amazon equals net losses of diversity for microbial communities
(University of Texas at Arlington) Research from an international team of microbiologists has revealed a new concern about deforestation in the Amazon rainforest -- a troubling net loss in the diversity among the microbial organisms responsible for a functioning ecosystem. Scientists worry that the loss of genetic variation in bacteria across a converted forest could reduce ecosystem resilience.
Source: EurekAlert! - Biology - December 24, 2012 Category: Biology Source Type: news
Cloning and expression of synthetic genes encoding ACE inhibitory bioactive peptides in Bifidobacterium pseudocatenulatum
Abstract A wide range of biopeptides potentially able to lower blood pressure through inhibition of the Angiotensin‐I Converting Enzyme are produced in fermented foods by proteolytic starter cultures. This work applies a procedure based on recombinant DNA technologies for the synthesis and expression of three ACE‐inhibitory peptides using a probiotic cell factory. ACE‐inhibitory genes and their pro‐active precursors were designed, synthesized by PCR, and cloned in Escherichia coli; after which, they were cloned into the pAM1 E. coli‐bifidobacteria shuttle vector. After E. coli transformation, constructs carrying ...
Source: FEMS Microbiology Letters - December 24, 2012 Category: Microbiology Authors: Luca Losurdo, Laura Quintieri, Leonardo Caputo, Raffaele Gallerani, Baltasar Mayo, Francesca Leo Tags: Research Letter Source Type: research
Enzymatic and genetic characterization of the DasD protein possessing N‐acetyl‐β‐D‐glucosaminidase activity in Streptomyces coelicolor A3(2)
Abstract The dasD gene is located just downstream of the dasABC gene cluster, encoding components of an ABC transporter for uptake of a chitin‐degradation product N,N’‐diacetylchitobiose [(GlcNAc)2] in Streptomyces coelicolor A3(2). To clarify the roles of the DasD protein in the degradation and assimilation of chitin, we obtained and characterized a recombinant DasD protein and a dasD‐null mutant of S. coelicolor A3(2). The recombinant DasD protein produced in Escherichia coli showed N‐acetyl‐β‐D‐glucosaminidase (GlcNAcase) activity and its optimum temperature and pH were 40°C and 7, respectively. dasD t...
Source: FEMS Microbiology Letters - December 24, 2012 Category: Microbiology Authors: Akihiro Saito, Hiroki Ebise, Yukari Orihara, Satoshi Murakami, Yukari Sano, Akane Kimura, Yuuta Sugiyama, Akikazu Ando, Takeshi Fuj, Kiyotaka Miyashita Tags: Research Letter Source Type: research
Taguchi Optimization of Duplex PCR for Simultaneous Identification of Staphylococcus aureus and Clostridium perfringens Alpha Toxins
Abstract Staphylococcus aureus and Clostridium perfringens are two major bacteria that infect open wounds and delay the process of healing. The rapid and progressive deterioration of soft tissue during S. aureus and C. perfringens co‐infections is due to analogous necrotic alpha toxins produced by both the organisms. The aim of this study was to determine the alpha toxins of S. aureus and C. perfringens by duplex PCR. The PCR assay employed two sets of primers; hlaf/r to amplify staphylococcal alpha toxin gene hla (274 bp) and cpaf/r to amplify clostridial alpha toxin gene cpa (398 bp) along with a competitive internal a...
Source: FEMS Microbiology Letters - December 24, 2012 Category: Microbiology Authors: Siva Ramakrishna Uppalapati, Jeyabalaji Joseph Kingston, Harishchandra Sripathi Murali, Harsh Vardhan Batra Tags: Research Letter Source Type: research
Liquid egg white pasteurization using a centrifugal UV irradiator.
The objective of this study was to inactivate Escherichia coli using a UV irradiator that centrifugally formed a thin film of LEW on the inside of a rotating cylinder. The LEW was inoculated with E. coli K12 to approximately 8log cfu/ml and was processed at the following conditions: UV intensity 1.5 to 9.0mW/cm(2); cylinder rotational speed 450 to 750RPM, cylinder inclination angle 15° to 45°, and flow rate 300 to 900ml/min, and treatment time 1.1 to 3.2s. Appropriate dilutions of the samples were pourplated with tryptic soy agar (TSA). Sublethal injury was determined using TSA+4% NaCl. The regrowth of surviving E. coli ...
Source: International Journal of Food Microbiology - December 23, 2012 Category: Food Science Authors: Geveke DJ, Torres D Tags: Int J Food Microbiol Source Type: research
[Successful treatment of life-threatening, treatment resistant Clostridium difficile infection associated pseudomembranous colitis with faecal transplantation].
Abstract Due to world-wide spread of hypervirulent and antibiotic resistant Clostridium difficile strains, the incidence of these infections are dramatically increasing in Hungary with appalling mortality and recurrence rates. Authors present a case of a 59-year-old patient who developed a severe, relapsing pseudomembranous colitis after antibiotic treatment. Life-threatening symptoms of fulminant colitis were successfully treated with prolonged administration of metronidazole and vancomycin, careful supportive therapy and weeks of intensive care. However, a well-documented, severe relapse developed within a week a...
Source: Orvosi Hetilap - December 23, 2012 Category: Journals (General) Authors: Nagy GG, Várvölgyi C, Paragh G Tags: Orv Hetil Source Type: research
The Staphylococcus aureus Opp1 ABC transporter imports nickel and cobalt in zinc‐depleted conditions and contributes to virulence
This study identifies a novel S. aureus trace metal transporter and its restricted conditions of activity, and establishes its role in infection.
Source: Molecular Microbiology - December 23, 2012 Category: Microbiology Authors: Laetitia Remy, Marie Carrière, Aurélie Derré‐Bobillot, Cécilia Martini, Maurizio Sanguinetti, Elise Borezée‐Durant Tags: Research Article Source Type: research
Development of functionalised polyelectrolyte capsules using filamentous Escherichia coli cells
Conclusion: The thus constructed new material offers possibilities for diverse applications like novel catalysts or metal nanowires for electrical devices. The novelty of this work is the use of filamentous E. coli templates and the use of S-layer proteins in a new material construct.
Source: Microbial Cell Factories - December 23, 2012 Category: Microbiology Authors: Franziska LedererTobias GüntherUlrike WeinertJohannes RaffKatrin Pollmann Source Type: research
Defining bacterial species in the genomic era: insights from the genus Acinetobacter
Conclusion: We believe a combination of core genome phylogenetic analysis and ANI provides an appropriate method for bacterial species delineation, whereby bacterial species are defined as monophyletic groups of isolates with genomes that exhibit at least 95% pair-wise ANI. The proposed method is backwards compatible; it provides a scalable and uniform approach that works for both culturable and non-culturable species; is faster and cheaper than traditional taxonomic methods; is easily replicable and transferable among research institutions; and lastly, falls in line with Darwin's vision of classification becoming, as far ...
Source: BMC Microbiology - Latest articles - December 23, 2012 Category: Microbiology Authors: Jacqueline ChanMihail HalachevNicholas LomanChrystala ConstantinidouMark Pallen Source Type: research
Application of protein purification methods for the enrichment of a cytotoxin from Campylobacter jejuni
Conclusions: We report the enrichment and partial purification of C. jejuni cytotoxin by HPLC ion-exchange chromatography. Further purification may be achieved using additional complementary chromatographic techniques. A short-list of six candidate cytotoxin proteins was identified using an LCMS screen of pool B. Successful isolation of the cytotoxin will initiate steps for the determination of the role of this cytotoxin in the pathogenesis of C. jejuni diarrhoea.
Source: BMC Microbiology - Latest articles - December 23, 2012 Category: Microbiology Authors: Xenia GatsosDavid SteerThamradeen JunaidA SmithBen AdlerM Albert Source Type: research
Waterborne outbreaks of cryptosporidiosis.
This article documents how waterborne Cryptosporidium outbreaks are identified and reported, how such outbreaks have acted as drivers of regulatory change, and some of the recent developments in the detection and investigation of these outbreaks and their spread, especially the application of molecular typing assays. PMID: 23247139 [PubMed - as supplied by publisher]
Source: Annali dell'Istituto Superiore di Sanita - December 22, 2012 Category: Global & Universal Authors: Chalmers RM Tags: Ann Ist Super Sanita Source Type: research
Letters to the Editor
In the October 15, 2012 issue of Clinical Microbiology Newsletter (Vol. 34, No. 20), an article entitled, “Multiparametric technologies for the diagnosis of syndromic infections” by Drs. Luc Bissonnette and Michael G. Bergeron was published. Below is a letter from Les C. Stutzman, Senior Product Manager, bioMérieux Canada, Inc. followed by Dr. Bissonnette's response.
Source: Clinical Microbiology Newsletter - December 22, 2012 Category: Microbiology Source Type: news
Metagenomics and Community Profiling: Culture-Independent Techniques in the Clinical Laboratory
Abstract: Clinical diagnostics for microbial pathogens often rely on culture or performing targeted molecular assays for identification. High-throughput culture-independent techniques offer a method to characterize individual isolates, as well as total microbial communities, without the need for cultivation or a priori knowledge of the organisms that may be present. Community profiling exploits universal marker genes present in bacteria, archaea, and fungi to explore diversity. Using bulk DNA/RNA sequencing, metagenomics can be applied to microbial populations. Here, we review these methods and their use to describe m...
Source: Clinical Microbiology Newsletter - December 22, 2012 Category: Microbiology Authors: Dana Willner, Phil Hugenholtz Source Type: news
Comparative transcriptomics with a motility deficient mutant leads to identification of a novel polysaccharide secretion system in Nostoc punctiforme
Summary Many filamentous cyanobacteria are capable of gliding motility by an undefined mechanism. Within the heterocyst‐forming clades, some strains, such as the Nostoc spp. and Fisherella spp., are motile only as specialized filaments termed hormogonia. Here we report on the phenotype of inactivation of a methyl‐accepting chemotaxis‐like protein in Nostoc punctiforme, designated HmpD. The gene hmpD was found to be essential for hormogonium development, motility, and polysaccharide secretion. Comparative global transcriptional profiling of the ΔhmpD strain demonstrated that HmpD has a profound effect on the transcri...
Source: Molecular Microbiology - December 22, 2012 Category: Microbiology Authors: Douglas D. Risser, John C. Meeks Tags: Research Article Source Type: research