O139霍乱弧菌肠毒素核苷酸序列分析

Nucleotide sequence analysis of cholera toxin in Vibrio cholerae O139

目的 探讨O139霍乱弧菌肠毒素 (CTX)核苷酸与O1群霍乱CTX毒素核苷酸序列异同。方法 用聚合酶链反应、DNA序列分析测定 2株O139群、2株O1群古典型、2株O1群ElTor型霍乱弧菌CTXA2 B亚单位核苷酸。结果 2株O139群霍乱弧菌均含有CTXA2 B亚单位基因 ,O139群与O1群CTXA2 B核苷酸同源性为 97.1%～ 98.9%。结论 O139群与O1群霍乱弧菌CTXA2 B核苷酸基本同源。进一步证实两者CTX核苷酸序列一致。

Objective To investigate the difference of nucleotide sequence between cholera toxin (CTX) of O139 and O1 Vibrio cholerae.Methods Polymerase chain reaction and DNA sequence analysis were used to study 2 strains of O139, 2 strains of classical biotype and 2 strains of El Tor biotype.Results Both the 2 strains of cholerae O139 contained the fragment of CTX A 2 B gene, and the homology befween O1 and O139 serogroups was 98.9%～97.1%.Conclusion The nucleotide sequence of CTX A 2 B in Vibrio cholerae O139 was almost consistent with that in O1, which reconfirmed the consistence of the nucleotide sequence of CTX in the 2 serogroups of Vibrio cholorae .