Genome sequence of hybrid Vibrio cholerae O1 MJ-1236, B-33, and CIRS101 and comparative genomics with V. cholerae

Abstract

The genomes of Vibrio cholerae O1 Matlab variant MJ-1236, Mozambique O1 El Tor variant B33, and altered O1 El Tor CIRS101 were sequenced. All three strains were found to belong to the phylocore group 1 clade of V. cholerae, which includes the 7th-pandemic O1 El Tor and serogroup O139 isolates, despite displaying certain characteristics of the classical biotype. All three strains were found to harbor a hybrid variant of CTX Phi and an integrative conjugative element (ICE), leading to their establishment as successful clinical clones and the displacement of prototypical O1 El Tor. The absence of strain-and group-specific genomic islands, some of which appear to be prophages and phage-like elements, seems to be the most likely factor in the recent establishment of dominance of V. cholerae CIRS101 over the other two hybrid strains.