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Cholera caused by Vibrio cholerae O139 was first reported in Bangladesh and India in 1992. To determine the genomic epidemiology and origins of O139 in China, we sequenced 104 O139 isolates collected from Zhejiang Province, China, during 1994-2018 and compared them with 57 O139 genomes from other countries in Asia. Most Zhejiang isolates fell into 3 clusters (C1-C3), which probably originated in India (C1) and Thailand (C2 and C3) during the early 1990s. Different clusters harbored different antimicrobial resistance genes and IncA/C plasmids. The integrative and conjugative elements carried by Zhejiang isolates were of a new type, differing from ICEVchInd4 and SXT MO10 by single-nucleotide polymorphisms and presence of genes. Quinolone resistance-conferring mutations S85L in parC and S83I in gyrA occurred in 71.2% of the Zhejiang isolates. The ctxB copy number differed among the 3 clusters. Our findings provided new insights for prevention and control of O139 cholera .

Cholera caused by Vibrio cholerae O139 was first reported in Bangladesh and India in 1992. To determine the genomic epidemiology and origins of O139 in China, we sequenced 104 O139 isolates collected from Zhejiang Province, China, during 1994–2018 and compared them with 57 O139 genomes from other countries in Asia. Most Zhejiang isolates fell into 3 clusters (C1–C3), which probably originated in India (C1) and Thailand (C2 and C3) during the early 1990s. Different clusters harbored different antimicrobial resistance genes and IncA/C plasmids. The integrative and conjugative elements carried by Zhejiang isolates were of a new type, differing from ICEVchInd4 and SXTMO10 by single-nucleotide polymorphisms and presence of genes. Quinolone resistance–conferring mutations S85L in parC and S83I in gyrA occurred in 71.2% of the Zhejiang isolates. The ctxB copy number differed among the 3 clusters. Our findings provided new insights for prevention and control of O139 cholera .

In developing countries threat of cholera is a significant health concern whenever water purification and sewage disposal systems are inadequate. Vibrio cholerae is one of the responsible bacteria involved in cholera disease. The complete genome sequence of V. cholerae deciphers the presence of various genes and hypothetical proteins whose function are not yet understood. Hence analyzing and annotating the structure and function of hypothetical proteins is important for understanding the V. cholerae. V. cholerae O139 is the most common and pathogenic bacterial strain among various V. cholerae strains. In this study sequence of six hypothetical proteins of V. cholerae O139 has been annotated from NCBI. Various computational tools and databases have been used to determine domain family, protein-protein interaction, solubility of protein, ligand binding sites etc. The three dimensional structure of two proteins were modeled and their ligand binding sites were identified. We have found domains and families of only one protein. The analysis revealed that these proteins might have antibiotic resistance activity, DNA breaking-rejoining activity, integrase enzyme activity, restriction endonuclease, etc. Structural prediction of these proteins and detection of binding sites from this study would indicate a potential target aiding docking studies for therapeutic designing against cholera.

The emergence of Vibrio cholerae O139 Bengal during 1992-1993 was associated with large epidemics of cholera in India and Bangladesh, and initially, with a total displacement of the existing Vibrio cholerae O1 strains. However, the O1 strains reemerged in 1994 and initiated a series of disappearance and re-emergence of either of the two serogroups that were associated with temporal changes sustained by the strains. Molecular studies using restriction fragment polymorphism analysis of CTXΦ phage in toxigenic Vibrio cholerae O139 have been a useful tool used to study the above mentioned changes. Those studies have shown clonal diversity among the O139 strain and continues emergence of new epidemic clones, reflected by changes in the structure, organization and location of the CTXΦ prophages in the Vibrio cholerae O139 chromosome. Here it was reviewed the available information about this subject and it was reported the finding of two strains from India containing several copies of CTXΦ with and without cholera toxin coexisting in the same strain. The ctx-gene-negative copies could be considered putative CTXΦ precursors and they are both types Calcuta and El Tor. Comparative nucleotide sequence analysis revealed certain differences with other reported precursors, suggesting a different origin. The strains here examined, possess CTXΦ copies of different immunity groups. The implication of this finding in the concept of heteroimmunity and in the vaccine design is discussed. [ABSTRACT FROM AUTHOR]