最小弧菌热不稳定型溶血素基因克隆与序列分析

根据已发表的最小弧菌热不稳定型溶血素（heat-labile hemolysin）基因核苷酸序列，设计和合成一对特异性引物，以最小弧菌96-6-3的基因组DNA为模板，PCR扩增得到热不稳定型溶血素基因片段，克隆到质粒载体pMD-18T中进行测序和分析．其结果表明扩增的热不稳定型溶血素基因片段与已发表的最小弧菌热不稳定型溶血素的同源性高达98％，扩增片段编码由446个氨基酸组成的多肽，推测分子量为50200．软件分析表明编码的氨基酸有较高的抗原性，可作为基因工程疫苗的候选基因片段．

Cloning and sequence analysis of a heat-abile hemolysin of Vibrio mimicus

A pair of primers was designed according to the reported nucleotide labile hemolysin gene of Vibrio mimicus. With the specific primers, one target sequences of the heatfragment about 1 338 bp was amplified from Vibrio mimicus strain 96-6-3 DNA via PCR. The PCR products were cloned into pMD18-T vector and sequenced. The sequence was compared with the corresponding regions of the GenBank strains and the nucleotide sequence was predicted to encode a 446 aa protein with the molecular weight of 50 200 and with high antigenicity. It was suggested that the amplified sequence of heat-labile hemolysin gene can be used as a candidate fragment for genetic engineering vaccine. We hope it can boost the research and application of the genetic engineering vaccine, so will expedite the development of aquaculture in our country, and at the same time, provide some evidence for a profound study of the mechanism of fish vaccinology.