A new combination of O- and K-antigens of a Vibrio parahaemolyticus strain isolated from a patient with diarrhea

Vibrio parahaemolyticus strain 10260 was isolated from a patient with diarrhea. Biochemical and serological characters of the strain were analyzed. This strain possessed a new combination of O- and K-antigens. From the results of this study, the serotype of V. parahaemolyticus strain 10260 was proposed as O1:K20.     

Genetic transformation of Vibrio parahaemolyticus, Vibrio alginolyticus, and Vibrio cholerae non O-1 with plasmid DNA by electroporation

An electroporation procedure for the plasmid-mediated transformation of the genus Vibrio was performed, as part of an effort to develop recombinant DNA techniques for genetic manipulation of the genus Vibrio. Vibrio parahaemolyticus, V. alginolyticus, and V. cholerae non O-1 (9 different strains) were transformed with 3 vector plasmids (pACYC184, pHSG398, and pBR325). The efficiency of transformation was highly dependent on three parameters: the concentration of plasmid DNA; the strength of the electric field; and the combination of plasmid DNA and recipient strain. The drug-resistance genes on the vector plasmid were expressed in the Vibrio strains.     

Occurrence and distribution of virulent strains of Vibrio parahaemolyticus in seafoods marketed from Cochin (India)

This study was aimed for the detection of Vibrio parahaemolyticus by biochemical and molecular methods in seafood samples collected from the markets of Cochin located at the southwest coast of India. A total of seventy-two V. parahaemolyticus cultures were isolated by selecting sucrose and cellobiose non-fermenting colonies. All the biochemically confirmed strains were found to have 368-bp toxR gene fragment, while an additional 24% of the samples were confirmed as V. parahaemolyticus by toxR based polymerase chain reaction (PCR) from enrichment broths. PCR based methods are used to detect tdh, trh, and orf8 genes for the identification of pathogenic and pandemic V. parahaemolyticus. Only one out of two urease positive isolates amplified the trh (500bp) gene. About 10% of the isolates showed weak haemolysis and none were found to amplify tdh (269 bp) and orf8 (746 bp) genes, thus indicating the meager incidence of pandemic strains from this area. The incidence of trh positive isolates from market samples signals towards the adoption of stringent seafood safety measures for the products meant for human consumption.