Bacterial pathogens

Fri, 02/05/2016 - 11:01
The synergistic antimicrobial effects of phytic acid (PA), a natural extract from rice bran, plus sodium chloride against Escherichia coli O157:H7 were examined. Exposure to NaCl alone at concentrations up to 36% (wt/wt) for 5 min did not reduce bacterial populations. The bactericidal effects of PA alone were much greater than those of other organic acids (acetic, citric, lactic, and malic acids...
Fri, 02/05/2016 - 11:01
Shiga toxin-producing Escherichia coli (STEC) serotype O145 is one of the major non-O157 serotypes associated with severe human disease. Here we examined the genetic diversity, population structure, virulence potential, and antimicrobial resistance profiles of environmental O145 strains recovered from a major produce production region in California. Multilocus sequence typing analyses revealed...
Fri, 02/05/2016 - 11:01
Vibrio parahaemolyticus is a bacterial pathogen that can cause illness after the consumption or handling of contaminated seafood. The primary virulence factors associated with V. parahaemolyticus illness are thermostable direct hemolysin (TDH) and Tdh-related hemolysin (TRH). However, clinical strains lacking tdh and trh have recently been isolated, and these clinical isolates are poorly...
Fri, 02/05/2016 - 11:01
Listeria monocytogenes is a saprophytic bacterium that thrives in diverse environments and causes listeriosis via ingestion of contaminated food. RsbX, a putative sigma B (B) regulator, is thought to maintain the ready state in the absence of stress and reset the bacterium to the initial state in the poststress stage in Bacillus subtilis. We wondered whether RsbX is functional in L. monocytogenes...
Fri, 02/05/2016 - 11:01
Increasing evidence indicates that despite exposure to harsh environmental stresses, Salmonella enterica successfully persists on plants, utilizing fresh produce as a vector to animal hosts. Among the important S. enterica plant colonization factors are those involved in biofilm formation. S. enterica biofilm formation is controlled by the signaling molecule cyclic di-GMP and represents a sessile...
Fri, 02/05/2016 - 04:09
Publication date: Available online 4 February 2016 Author(s): Bongkot Ngamsom, Maria J. Lopez-Martinez, Jean-Claude Raymond, Patrick Broyer, Pradip Patel, Nicole Pamme Pathogen analysis in food samples routinely involves lengthy growth-based pre-enrichment and selective enrichment of food matrices to increase the ratio of pathogen to background flora. Similarly, for blood culture...
Fri, 02/05/2016 - 04:09
Publication date: Available online 4 February 2016 Author(s): Judit K. Kovács, Györgyi Horváth, Monika Kerényi, Béla Kocsis, Levente Emődy, György Schneider Direct bioautography is a useful method to identify antimicrobial compounds with potential therapeutic importance. Because of technical limitations till now, it has been applied only for aerobic bacteria. In this work we...
Thu, 02/04/2016 - 17:46
Abstract Two-component systems (TCSs) play important roles in the adaptation of bacteria to stress. Despite their increasingly well understood mechanistic features, it remains poorly understood how TCSs transduce signals across membranes. Here, we use the E. coli Cu/Ag-responsive CusSR TCS as a model to investigate the roles of CusS transmembrane (TM) residues. Proline scanning of TM1 domain led...
Thu, 02/04/2016 - 10:36
Publication date: 2 April 2016 , Volume 222 Author(s): Yinqiang Cai, Jing Tao, Yang Jiao, Xiao Fei, Le Zhou, Yan Wang, Huijuan Zheng, Zhiming Pan, Xinan Jiao An epidemiological investigation of Salmonella spp. in pig and pork samples from one slaughterhouse and its downstream retail markets in Yangzhou, Jiangsu Province, China, was conducted from October 2013 to March 2014....
Thu, 02/04/2016 - 07:58
Publication date: Available online 3 February 2016 Author(s): S. Gutiérrez, H. Martínez-Blanco, L.B. Rodríguez-Aparicio, M.A. Ferrero In this study, the effect that 5 fermented broths of lactic acid bacteria (LAB) strains have on the viability or proliferation and adhesion of 7 potentially pathogenic microorganisms was tested. The fermented broth from Lactococcus lactis C660 had a...
Thu, 02/04/2016 - 07:58
Publication date: Available online 3 February 2016 Author(s): R. Wolf, K. Orsel, J. De Buck, U. Kanevets, H.W. Barkema Mycobacterium avium ssp. paratuberculosis (MAP) causes Johne's disease, a production-limiting disease in cattle. Detection of infected herds is often done using environmental samples (ES) of manure, which are collected in cattle pens and manure storage areas....
Thu, 02/04/2016 - 07:58
Publication date: Available online 3 February 2016 Author(s): Conrado Carrascosa, Rafael Millán, Pedro Saavedra, José Raduán Jaber, António Raposo, Esther Sanjuán The purpose of this paper was to evaluate, by statistical analyses, risk factors on cheese farms that can influence the microbial contamination of their products. Various assessment tools, such as cheese production...
Thu, 02/04/2016 - 04:04
Publication date: Available online 3 February 2016 Author(s): Mingxing Tian, Jing Qu, Yanqing Bao, Jianpeng Gao, Jiameng Liu, Shaohui Wang, Yingjie Sun, Chan Ding, Shengqing Yu Brucellosis, the most common widespread zoonotic disease, is caused by Brucella spp., which are facultative, intracellular, Gram-negative bacteria. With the development of molecular biology...
Wed, 02/03/2016 - 11:48
A study was conducted examining the effects of prebiotics and probiotics separately and in combination on growth parameters, fecal and cecal microbiota. Six dietary treatments consisted of: 1) control, 2) control + 0.2 lb/ton calculated to contain 1 x 1010 Pediococcus acidilactici/kg, 3) control + 0.2 lb/ton calculated to contain 2 x 1010 live Saccharomyces cerevisiae boulardii/kg, 4) control + 2...
Wed, 02/03/2016 - 11:48
Acid injury could prevent detection of Salmonella in feed and feed-type samples. A previous study showed that after incubation in commonly used pre-enrichment media, mixed feeds and feed ingredients reached a pH (4.0 to 5.0), capable of injuring or killing Salmonella. Approximately 105 colony forming units (CFU) of S. Enteritidis (SE), S. Heidelberg (SH), S. Kentucky (SK), or S. Typhimurium (ST)...
Tue, 02/02/2016 - 13:35
Abstract AimsThis study observed the behavior of probiotics and selected bacterial pathogens co-inoculated into peanut butter during gastrointestinal simulation. Methods and ResultsPeanut butter homogenates co-inoculated with Salmonella/Listeria strains (5 log CFU ml−1) and lyophilized or cultured probiotics (9 log CFU ml−1) were exposed to simulated gastrointestinal conditions for 24 h at 37°C....
Tue, 02/02/2016 - 11:41
Publication date: August 2016 , Volume 66 Author(s): Haiying Cui, Cuixia Ma, Lin Lin This study aims to evaluate the antimicrobial effects of cold nitrogen plasma (CNP) and clove oil against Escherichia coli O157:H7 (E. coli O157:H7) biofilm on lettuce. Both clove oil (1 mg/mL, 2 mg/mL and 4 mg/mL) and CNP (400–600 W) displayed significant eradication effect on E. coli O157:H7 biofilms...
Tue, 02/02/2016 - 06:47
Publication date: February 2016 , Volume 99, Issue 2 Author(s): R. Li, P. Fei, C.X. Man, B.B. Lou, J.T. Niu, J. Feng, L.H. Sun, M.Y. Li, Y.J. Jiang This study evaluated the antimicrobial activity of tea polyphenols (TP) against 4 Cronobacter sakazakii strains with different sequence types (ST) isolated from powdered infant formula (PIF). The results showed that in normal...
Tue, 02/02/2016 - 06:47
Publication date: February 2016 , Volume 99, Issue 2 Author(s): L.J. Levison, E.K. Miller-Cushon, A.L. Tucker, R. Bergeron, K.E. Leslie, H.W. Barkema, T.J. DeVries Mastitis is a common and costly production disease on dairy farms. In Canada, the incidence rate of clinical mastitis (IRCM) has been determined for conventionally managed dairy farms; however, no studies to date have...
Tue, 02/02/2016 - 06:47
Publication date: February 2016 , Volume 99, Issue 2 Author(s): L.B. da Costa, P.J. Rajala-Schultz, G.M. Schuenemann Staphylococcus aureus is the most common contagious mastitis pathogen affecting cows worldwide. Practices to control this organism have been advocated for decades, and identification of risk factors in individual herds is crucial in prevention and control of Staph....
Tue, 02/02/2016 - 06:47
Publication date: February 2016 , Volume 99, Issue 2 Author(s): Fernanda Fernandes dos Santos, Letícia Caldas Mendonça, Daniele Ribeiro de Lima Reis, Alessandro de Sá Guimarães, Carla Christine Lange, João Batista Ribeiro, Marco Antonio Machado, Maria Aparecida Vasconcelos Paiva Brito Bacteria of the genus Staphylococcus are one of the major pathogens causing bovine mastitis....
Mon, 02/01/2016 - 17:00
Mateusz Rawski, Bartosz Kierończyk, Jakub Długosz, Sylwester Świątkiewicz, Damian Józefiak Probiotics are widely used in nutrition, and their mode of action is intensively studied in mammals and birds; however, it is almost unknown in reptiles. In the present study, Trachemys scripta scripta and Sternotherus odoratus were used to assess the effects of dietary probiotics on chelonian...
Mon, 02/01/2016 - 14:30
Cryo-electron tomography (cryo-ET) has emerged as a leading technique for three-dimensional visualization of large macromolecular complexes and their conformational changes in their native cellular environment. However, the resolution and potential applications of cryo-ET are fundamentally limited by specimen thickness, preventing high-resolution in situ visualization of macromolecular structures...
Mon, 02/01/2016 - 14:30
The alternative sigma factor H has two functions in Gram-positive bacteria: it regulates sporulation or the development of genetic competence. Listeria monocytogenes is a non-sporulating species in which competence has not yet been detected. Nevertheless, the main competence regulators and a series of orthologous genes that form the competence machinery are present in its genome; some of the...
Mon, 02/01/2016 - 14:30
Feo is the major ferrous iron transport system in prokaryotes. Despite being discovered over 25 years ago and found to be widely distributed among bacteria, Feo is poorly understood, as its structure and mechanism of iron transport have not been determined. The feo operon in V. cholerae is made up of three genes, encoding the FeoA, FeoB, and FeoC proteins, which are all required for Feo system...
Mon, 02/01/2016 - 03:35
Abstract Aimsevaluation of the efficacy of marine LAB, Lactobacillus plantarum AH 78, on growth performance and immune response of Nile tilapia (Oreochromis niloticus) challenged with Aeromonas hydrophila. Methods and ResultsMarine probiotic, L. plantarum AH 78, was incorporated in Nile tilapia diets at 0.0, 0.5, 1.0 or 2.0% (w/w). The diets were fed to juvenile Nile tilapia for 40 days, after...
Fri, 01/29/2016 - 17:00
Carrie E. Schmidt, Smriti Shringi, Thomas E. Besser Escherichia coli O157:H7 is a food-borne bacterium that causes hemorrhagic diarrhea and hemolytic uremic syndrome in humans. While cattle are a known source of E. coli O157:H7 exposure resulting in human infection, environmental reservoirs may also be important sources of infection for both cattle and humans. Bacteriophage-encoded Shiga toxins...
Fri, 01/29/2016 - 17:00
Hattie E. Webb, Marie Bugarel, Henk C. den Bakker, Kendra K. Nightingale, Sophie A. Granier, H. Morgan Scott, Guy H. Loneragan Objective A study was conducted to recover carbapenem-resistant bacteria from the faeces of dairy cattle and identify the underlying genetic mechanisms associated with reduced phenotypic susceptibility to carbapenems. Methods One hundred and fifty-nine faecal samples from...
Fri, 01/29/2016 - 05:37
Publication date: Available online 29 January 2016 Author(s): L.A. Jimenez-Maroto, A. Lopez-Hernandez, D.L. Borneman, S.A. Rankin Anecdotal information suggests that some Hispanic consumers may consider US-made Hispanic cheeses as having a general lack of authenticity compared with those made in their countries of origin. To characterize the potential differences, samples of fresh,...
Fri, 01/29/2016 - 05:01
LWT
Publication date: June 2016 Source:LWT - Food Science and Technology, Volume 69 Author(s): Pei-jun Li, Jin-lan Xia, Zhen-yuan Nie, Yang Shan Orange peel wastes were enzymatically depolymerized into pectic oligosaccharides (POS) by multi-enzyme complexes from Aspergillus japonicus PJ01. The hydrolyzate was fractionated via membrane separation into three fractions: POS1 <1 kDa; 1...
Thu, 01/28/2016 - 17:00
Joshua D. Rouch, Andrew Scott, Nan Ye Lei, R. Sergio Solorzano-Vargas, Jiafang Wang, Elaine M. Hanson, Masae Kobayashi, Michael Lewis, Matthias G. Stelzner, James C. Y. Dunn, Lars Eckmann, Martín G. Martín Background & Aims Intestinal microfold (M) cells are specialized epithelial cells that act as gatekeepers of luminal antigens in the intestinal tract. They play a critical role in the...
Thu, 01/28/2016 - 11:01
We describe a simple protocol to inactivate the biosafety level 3 (BSL3) pathogens Brucella prior to their analysis by matrix-assisted laser desorption ionization–time of flight mass spectrometry. This method is also effective for several other bacterial pathogens and allows storage, and eventually shipping, of inactivated samples; therefore, it might be routinely applied to unidentified...
Thu, 01/28/2016 - 11:01
Recent outbreaks of carbapenem-resistant Enterobacteriaceae infections associated with duodenoscopes used for endoscopic retrograde cholangiopancreatography have highlighted the challenge of cleaning and high-level disinfection of these instruments. The Food and Drug Administration has suggested that duodenoscope surveillance by microbiological culturing, along with strict adherence to...
Thu, 01/28/2016 - 11:01
Whole-genome sequencing (WGS) has emerged as a powerful tool for comparing bacterial isolates in outbreak detection and investigation. Here we demonstrate that WGS performed prospectively for national epidemiologic surveillance of Listeria monocytogenes has the capacity to be superior to our current approaches using pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST),...
Thu, 01/28/2016 - 11:01
The potential to rapidly capture the entire microbial community structure and/or gene content makes metagenomic sequencing an attractive tool for pathogen identification and the detection of resistance/virulence genes in clinical settings. Here, we assessed the consistency between PCR from a diagnostic laboratory, quantitative PCR (qPCR) from a research laboratory, 16S rRNA gene sequencing, and...
Thu, 01/28/2016 - 11:01
Salmonella enterica serovar Heidelberg is the second most frequently occurring serovar in Quebec and the third-most prevalent in Canada. Given that conventional pulsed-field gel electrophoresis (PFGE) subtyping for common Salmonella serovars, such as S. Heidelberg, yields identical subtypes for the majority of isolates recovered, public health laboratories are desperate for new subtyping tools to...
Thu, 01/28/2016 - 09:46
Publication date: Available online 28 January 2016 Author(s): Jung-Whan Chon, Young-Ji Kim, Hong-Seok Kim, Dong-Hyeon Kim, Kwang-Young Song, Kidon Sung, Kun-Ho Seo Although cefoperazone is the most commonly used antibiotic in Campylobacter-selective media, the distribution of cefoperazone-resistant bacteria such as extended-spectrum beta-lactamase (ESBL)-producing Escherichia...

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