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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 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.

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 .

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]

Several attempts have been made to obtain a vaccine candidate against Vibrio cholerae O139, but the efficacy of those prototypes remains to be confirmed by studies in volunteers. The present work describes the construction of two new atoxigenic mutants derived from a recently isolated wild type Vibrio cholerae O139, strain which shows a good colonization index of the suckling mice intestine and a better antibiotic susceptibility pattern compared with other vaccine candidates. Genetic manipulations allowing CTXF genome deletion in these mutants were made using the suicide plasmid methodology. The constructed plasmid allows effective manipulations of the genome of V. cholerae strains irrespective of the CTXF prophage genetic array on the chromosome. Both mutants, here obtained, as well as their parental strain show normal phenotypes in traits as motility, expression of MSHA, ToxR and OmpU, although they produce no hemagglutinin protease in vitro. The atoxigenic mutants were highly attenuated as judge by the level of surviving in the infant mice cholera model compared with their parental strain which resulted very virulent in the same model. Besides, they also retained the capacity to colonize the mice bowel, however one of them shows better colonization index and it was chosen to be further modified in order to improve its biosafety properties. [ABSTRACT FROM AUTHOR]

Ribotyping has been widely used to characterise the seventh pandemic clone including South American and O139 variants which appeared in 1991 and 1992 respectively. To reveal the molecular basis of ribotype variation we analysed the rrn operons and their flanking regions. All but one variation detected by BglI, the most discriminatory enzyme, was found to be due to changes within the rrn operons, resulting from recombination between operons. The recombinants are detected because of the presence of a BglI site in the 16S gene in three of the nine rrn operons and/or changes of intergenic spacer types of which four variants were identified. As the frequency of rrn recombination is high, ribotyping becomes a less useful tool for evolutionary studies and long term monitoring of the pathogenic clones of Vibrio cholerae as variation could undergo precise reversion by the same recombination event.

The growth of Vibrio cholerae O139 inoculated into cendol (a mixture of coconut milk, brown sugar, and green jelly from rice flour), rojak (prawn paste, sugar, soy sauce, spices, garlic, and peanut gravy), gravy, tofu, fried tofu, and wheat-flour noodles (all except rojak gravy containing the natural microbial flora) was examined at four incubation temperatures (7, 15,25, and 35°C). V. cholerae O139 grew well in cendol incubated at 25 and 35°C but not at 15°C or below. No growth of V. cholerae O139 in rojak gravy was detected at any temperature except for very slow growth at 35°C. V. cholerae O139 inoculated into tofu exhibited slow growth at 25 and 35°C and growth was not detected at 7 and 15°C. However, in fried tofu, the organism entered the growth phase after 12 h of incubation at 25 and 35°C. Growth of V. cholerae O139 was not demonstrated in noodles at any incubation temperatures. Nutrient broth with 1% NaCl added supported the growth of V. cholerae O139 at 25 and 35°C. At both of these incubation temperatures mean generation time was longer at pH 5 than at pH 8. The high variation in growth of V. cholerae O139 in the distinct foods examined might have been due to differences in pH, fat content, and a w . Proper sanitary practices and storage of foods at refrigeration temperatures will help to reduce the possibility of growth by Vibrio cholerae O139 in foods to levels which do not imply a risk for food-poisoning.