Genetic diversity of VchintIA gene in super integron of O1 and O139 Vibrio cholerae isolates

Objective To understand the diversity of VchintIA gene of O1 and O139 V. cholerae and the relationship between the diversity of VchintIA and different lineages of V. cholerae. Methods Polymerase chain reaction, sequencing and bioinformatics analysis were conducted in this study. Results The VchintIA gene amplification was conducted for all tested strains. The sequences of VchintIA gene were identical in toxigenic O1 El Tor, toxgenic O139 and tcp-gene-cluster positive nontoxigenic O1 El Tor strains. The VchintIA gene in tcp-gene-cluster negative nontoxigenic O1 El Tor strains only showed variation at nucleotide level, however, nontoxigenic O139 strains showed the variation in both nucleotide acid level and amino acid level. Conclusion The diversity of VchintIA at both nucleotide acid le4vel and amino acid level were observed in O1 and O139 V. cholerae strains. This variation in the VchintIA of nontoxigenic O139 strains may play certain role in the structural variation of super integron in these strains.