Study on structures of new types of CTX~U and nct-CTX~U genomes

ObjectiveTo study on structures of new types of CTXU and nct-CTXU genomes of EI Tor biotype vibrio cholerae.MethodsPCR,sequencing and sequence analysis were conducted.ResultsOnly nct-CTX^classU,CTX^classU,or CTX^ETU genome type,nct-CTX^classU and CTX^ETU,nct-CTX^newETU and CTX^classU genomes coexisted types in EI Tor strains isolated from China were found.Different rates of last 60 bp of zot gene and Zot of CTXU and nct-CTXU were 40% and 60%.Identities of ig1,rstR,iggene and RstR of class、ET and newET types were 77.0%~97.4%,10.4%~17.9%, 9.6%~64.8%,and 9.2%~24.1% differentially.Different types of CTXU genome were found near TLC cluster.Identities of tcpA,TcpA,ctxA,ctxB,CtxA,and CtxB of strains in this study with others toxic EVC and O139 VC were over 99%, 99%,99%,98%,98%,and 96%.Conclusionnct-CTX^classU and CTX^ETU,nct-CTX^newETU and CTX^classU genomes coexisted types in EI Tor were found first.