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Vibrio Cholerae O1 (vibrio + cholerae_o1)
Selected AbstractsImmunogenicity of synthetic saccharide fragments of Vibrio cholerae O1 (Ogawa and Inaba) bound to Exotoxin AFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2006Terri K. Wade Abstract Recombinant exotoxin A (rEPA) from Pseudomonas aeruginosa conjugated to Vibrio cholerae O1 serotype-specific polysaccharides (mono-, di- and hexasaccharide) were immunogenic in mice. Monosaccharide conjugates boosted the humoral responses to the hexasaccharide conjugates. Prior exposure to purified Ogawa lipopolysaccharide (LPS) enabled contra -serotype hexasaccharide conjugates to boost the vibriocidal response, but Inaba LPS did not prime for an enhanced vibriocidal response by a contra -serotype conjugate. Prior exposure to the carrier, and priming B cells with the LPS of either serotype, resulted in enhanced vibriocidal titers if the Ogawa hexasaccharides were used, but a diminished response to the Inaba LPS. These studies demonstrate that the ,functional' B cell epitopes on the LPS differ from those of the neoglycoconjugates and that the order of immunization and the serotype of the boosting conjugate can influence the epitope specificity and function of the antisera. [source] GAMMA IRRADIATION ON FROZEN AND PACKAGED HEADED SHRIMPJOURNAL OF FOOD QUALITY, Issue 4 2009V.K.G. ABREU ABSTRACT The objective of this work was to evaluate the effects of , irradiation (0, 2, 4 and 6 kGy doses), applied on frozen and packaged headed shrimps, on pathogenic Vibrio cholerae O1 and Salmonella enteritidis bacteria, as well as on some of the physical and sensory characteristics of this kind of food. The 6 kGy dose was highly efficient in inhibiting V. cholerae O1 and S. enteritidis and in decreasing lipid oxidation in shrimps compared with the nonirradiated product. Shrimp texture was not affected by any of the irradiation doses studied, but the lightness of the surface color increased in shrimps irradiated with 6 kGy compared with those irradiated with 2 kGy. Shrimps irradiated with 6 kGy showed lower overall acceptability than those irradiated with 2 kGy or were nonirradiated. The application of , irradiation in doses up to 6 kGy on frozen and packaged headed shrimps could improve the microbiological quality of this commodity. PRACTICAL APPLICATIONS The use of , irradiation has the potential to ensure safety effectively by inactivating bacteria, increasing shelf life and maintaining food quality without significant chemical changes in the food matrix. Besides, this process can be applied to frozen and packaged products. Thus, irradiation of frozen and packaged shrimps could benefit the local processing industry, which could offer the international market a high-quality product, with an additional safety treatment. [source] Survival and Growth of Vibrio cholerae O1, Salmonella typhi, and Escherichia coli O157:H7 in Alfalfa SproutsJOURNAL OF FOOD SCIENCE, Issue 1 2000J. Castro-Rosas ABSTRACT: The survival and growth of Vibrio cholerae O1, Salmonella typhi, and Escherichia coli O157:H7 during germination and sprouting of disinfected alfalfa seeds and alfalfa sprouts was determined. All pathogens showed ability to grow during germination and sprouting, reaching counts of approximately 6.0 log10 CFU/g after 24 h. No growth was observed for any pathogen when the sprouts were inoculated after 24 h of seed germination. At this time, the background microflora was abundant. Numbers of pathogens inoculated on alfalfa sprouts decreased less than 1 log10 CFU/g over 15 d of refrigeration. Alfalfa sprouts can be an important factor contributing to the endemicity for typhoid fever and cholera in México. [source] Delineation of pilin domains required for bacterial association into microcolonies and intestinal colonization by Vibrio choleraeMOLECULAR MICROBIOLOGY, Issue 4 2000Thomas J. Kirn The toxin-co-regulated pilus (TCP), a type 4 pilus that is expressed by epidemic strains of Vibrio cholerae O1 and O139, is required for colonization of the human intestine. The TCP structure is assembled as a polymer of repeating subunits of TcpA pilin that form long fibres, which laterally associate into bundles. Previous passive immunization studies have suggested that the C-terminal region of TcpA is exposed on the surface of the pilus fibre and has a critical role in mediating the colonization functions of TCP. In the present study, we have used site-directed mutagenesis to delineate two domains within the C-terminal region that contribute to TCP structure and function. Alterations in the first domain, termed the structural domain, result in altered pilus stability or morphology. Alterations in the second domain, termed the interaction domain, affect colonization and/or infection by CTX-bacteriophage without affecting pilus morphology. In vitro and in vivo analyses of the tcpA mutants revealed that a major function of TCP is to mediate bacterial interaction through direct pilus,pilus contact required for microcolony formation and productive intestinal colonization. The importance of this function is supported by the finding that intragenic suppressor mutations that restore colonization ability to colonization-deficient mutants simultaneously restore pilus-mediated bacterial interactions. The alterations resulting from the suppressor mutations also provide insight into the molecular interactions between pilin subunits within and between pilus fibres. [source] | ||||||||||