Campylobacter jejuni is one of the leading causes of foodborne gastrointestinal illness worldwide. Here we performed ex vivo proteomic analysis of C. jejuni 81-176 in chicken, a main reservoir for human infection.
View Article and Find Full Text PDFPorcine edema disease (ED) is a communicable disease of shoats caused by infection with Shiga toxin (Stx)-producing Escherichia coli. Stx2e is classified as a 1A5B-type toxin and is a decisive virulence determinant of ED. The single A subunit of Stx2e possesses enzymatic activity and is accompanied by a pentamer of B subunits, which binds to the host receptor and delivers the A subunit into the cell.
View Article and Find Full Text PDFBiochem Biophys Res Commun
October 2012
Salmonella enterica serovar Typhimurium is a major cause of human gastrointestinal illness worldwide. This pathogen can persist in a wide range of environments, making it of great concern to public health. Here, we report that the salmonella pathogenicity island (SPI)-1 effector protein SipB exhibits a membrane topology that confers bacterial osmotolerance.
View Article and Find Full Text PDFListeria monocytogenes is a foodborne pathogen that causes gastroenteritis, maternofetal infections and meningoencephalitis in humans. Here we report that an intrahost genome mutation alters bacterial acid resistance and the abilities for replication/invasion in tissue cell culture. Among the L.
View Article and Find Full Text PDFTo evaluate disinfection methods for environments contaminated with bioterrorism-associated microorganism (Bacillus anthracis), we performed the following experiments. First, the sporicidal effects of sodium hypochlorite on spores of five bacterial species were evaluated. Bacillus atrophaeus was the most resistant to hypochlorite, followed in order by B.
View Article and Find Full Text PDFListeria monocytogenes causes listeriosis characterized by septicaemia, encephalitis, and abortion or stillbirth. Regular monitoring of its prevalence in food and characterization of its phenotypes and genotypes are necessary for disease surveillance and tracing the epidemic outbreaks. In this study, the prevalence of L.
View Article and Find Full Text PDFThe molecular epidemiology of 545 Salmonella enterica serovar Typhimurium isolates collected between 1977 and 2009 from cattle in Hokkaido, Japan, was investigated using pulsed-field gel electrophoresis (PFGE). Nine main clusters were identified from 116 PFGE patterns. Cluster I comprised 248 isolates, 243 of which possessed a sequence specific to definitive phage type 104 (DT104) or U302.
View Article and Find Full Text PDFPig edema disease is a bacterial disease caused by enterohemorrhagic Escherichia coli. E. coli produces Shiga toxin 2e (Stx2e), which is composed of one A subunit (Stx2eA) and five B subunits (Stx2eB).
View Article and Find Full Text PDFAsazuke is a ready-to-eat Japanese light pickle, mainly made of vegetables which are known to be one of the sources of Listeria monocytogenes contamination. Although asazuke is a popular side-dish in Japan, the hazard of bacterial contamination has not been evaluated yet. In this study, we investigated the prevalence of L.
View Article and Find Full Text PDFThe current treatment of botulism is to administer animal-derived antitoxin, which frequently causes severe adverse reactions in the recipients. In this study, a heavy chain antibody fragment (VH/V(H)H) phage display library was constructed by amplification of the immunoglobulin genes of a nonimmune camel, Camelus dromedarius, using primers specific to human VH gene segments. A recombinant light chain of type A botulinum toxin, BoTxA/LC, with zinc endoprotease activity was used in phage bio-panning to select phage clones displaying BoTxA/LC-bound VH/V(H)H.
View Article and Find Full Text PDFSalmonella enterica serotype Typhimurium (S. Typhimurium) definitive phage type (DT) 104 has become a widespread cause of human and other animal infections worldwide. The severity of clinical illness in S.
View Article and Find Full Text PDFFrom August 2007 until March 2008, we perfomed a detection and epidemiological analysis for Salmonella spp. in specimens collected from pork production chains to improve the quality of meat hygiene conditions in Hue, Vietnam. A total of 306 specimens were examined for Salmonella spp.
View Article and Find Full Text PDFHazard analysis of Listeria monocytogenes contamination during processing of salted walleye pollock (Theragra chalcogramma) roe was performed for a seafood plant in Japan from December 2005 to February 2006. As a result, L. monocytogenes number was detected on the pallet used for transport of barrels in the salting process and one of the rollers of the roller conveyor, which rotates while in contact with the bottoms of the barrels, but was not detected in any raw materials, interim products or final products.
View Article and Find Full Text PDFDuring an outbreak of enterohemorrhagic Escherichia coli (EHEC) O157, we showed previously that food isolates were resistant to oxidative stress, while patient isolates were sensitive to it. Because food isolates increased stress-sensitivity after mouse passage, this change most likely occurred during passage through patients. Here we demonstrate that the phenotypic change occurring during mouse passage correlates with the stress response of outer membrane protein W (OmpW) in EHEC O157 strains.
View Article and Find Full Text PDFEnterohemorrhagic Escherichia coli (EHEC) O157 strain F2, a food isolate of an outbreak, is resistant to oxidative stress, but has increased stress-sensitivity after passage through mice. The stress-sensitive variant of F2 (designated MP37) has decreased culturability, but retains membrane integrity under stress conditions, indicating that the cells enter a viable but non-culturable (VBNC) state. Proteomic analyses revealed that MP37 in the VBNC state had decreased levels of some oxidation-responsive factors (AhpCF, AceF), but it markedly increased levels of outer membrane protein W (OmpW).
View Article and Find Full Text PDFEpsilon-polylysine micro particles (SGEPL) and polyethyleneimine micro particles (SGPEI) were developed by the addition of a hydrophobic group and the immunological characterization of these micro particles and aluminum hydroxide (ALUM) was investigated. BALB/c mice were injected intraperitoneally with ovalbumin (OVA) as an antigen and SGEPL, SGPEI or ALUM as an adjuvant. The results showed that the mice injected with SGEPL produced a significant portion of anti-OVA antibody subclass IgG2a in the sera and suppressed interleukin (IL)-4 and IL-5, but enhanced IL-12 and interferon-gamma (IFN-gamma) from the spleen cells.
View Article and Find Full Text PDFAn indirect immunofluorescent assay to detect antibodies against the lipopolysaccharide (LPS) of Burkholderia pseudomallei and taxonomically closely related species was developed with the Luminex system. LPSs of Pseudomonas aeruginosa, Burkholderia cepacia, Burkholderia thailandensis, Burkholderia vietnamiensis, B. pseudomallei, and Burkholderia mallei were successfully conjugated to Luminex microspheres.
View Article and Find Full Text PDFVibrio cholerae is an aetiological agent of cholera that inhabits marine and estuarine environments. It can survive harsh environments by entering the viable but non-culturable (VBNC) state, but the related changes in gene expression have not been described. Here, we experimentally induced the VBNC state in V.
View Article and Find Full Text PDFThe protective-antigen (PA)-based cell-free vaccine is the only vaccine licensed for use against Bacillus anthracis infection in humans. Although the PA shows strong immunogenicity, the capsule or spore-associated somatic antigens may be important as additional vaccine targets for full protection against anthrax. In this study, the protective effect of spore-associated antigens against B.
View Article and Find Full Text PDFListeria monocytogenes is able to grow under conditions of high osmolarity. We constructed a deletion mutant of rpoN, encoding the alternative sigma factor RpoN, and analyzed its response to osmotic stress. In a minimal medium with 4% NaCl and 1 mM betaine, the mutant showed a similar growth to that of the parental strain, EGD.
View Article and Find Full Text PDFThe effect of morphine on the susceptibility of BALB/c mice to diarrheagenic Escherichia coli, Shigella flexneri, Listeria monocytogenes, Salmonella Enteritidis, Yersinia enterocolitica, was examined via the intraperitoneal inoculation. Morphine treatment increased the susceptibility to S. Enteritidis and L.
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