Molecular characterization of Vibrio cholerae non-O1/non-O139 isolated from coastal water of Arabian Gulf

摘要

The mechanism of pathogenic?Vibrio cholerae?to cause disease depends on the expression of virulence factors such as a potent cholera toxin (CT), and pilus colonization factor (toxin co-regulated pilus; TCP). The gene’s?molecular characterization provides?V. choleraeecology of the genes information about the ecology of?V. cholerae?which is an autochthonous inhabitant of aquatic environment as well as pathogenic for humans. ThectxAB?and?tcpA?genes are known to play a significant role in maintaining virulence in?V.cholerae, and these genes are believed to be exclusively associated with clinical strains of O1 and O139 serogroups. In this study, we examined the presence of virulence genes, including?ctxA?and?tcpA?(Classical and El Tor), as well as?toxR?and the genes responsible for O-antigen biosynthesis and for generation of serotype-specific determinants located in the?rfb?region in the?V. cholerae?chromosome. Out of 23 suspected?V. cholerae?isolated from Arabian Gulf coastal water of the eastern province of Saudi Arabia only one isolate was detected and harbored?tcpA (El Tor), O1rfb?and?toxR?genes. This study demonstrates the transfer of virulence genes among environmental strains of?V. cholerae?which appears to constitute an environmental reservoir of virulence genes, thereby providing new insights into the?V. cholerae?ecology. To the best of our knowledge, this is the first report of the isolation of?V. cholerae?from Arabian Gulf coastal water environment.