Retrospective genomic analysis of Vibrio cholerae O1 El Tor strains from different places in India reveals the presence of ctxB-7 allele found in Haitian isolates
التفاصيل البيبلوغرافية
العنوان:
Retrospective genomic analysis of Vibrio cholerae O1 El Tor strains from different places in India reveals the presence of ctxB-7 allele found in Haitian isolates
SUMMARYA total of 45 strains ofVibrio choleraeO1 isolated from 10 different places in India where they were associated with cases of cholera between the years 2007 and 2008 were examined by molecular methods. With the help of phenotypic and genotypic tests the strains were confirmed to be O1 El Tor biotype strains with classicalctxBgene. Polymerase chain reaction (PCR) analysis by double – mismatch amplification mutation assay PCR showed 16 of these strains carried thectxB-7allele reported in Haitian strains. Sequencing of thectxBgene in all the 45 strains revealed that in 16 strains the histidine at the 20th amino acid position had been replaced by asparagine and this single nucleotide polymorphism did not affect cholera toxin production as revealed by beads enzyme-linked immunosorbent assay. This study shows that the newctxBgene sequence was circulating in different places in India. Seven representatives of these 45 strains analysed by pulsed – field gel electrophoresis showed four distinctNot Idigested profiles showing that multiple clones were causing cholera in 2007 and 2008.
