大鲵致病性嗜水气单胞菌主要毒力基因的生物信息学分析

Cloning and bioinformatics analysis on main virulence gene of pathogenic Aeromonas hydrophila from Andrias davidianus

根据嗜水气单胞菌的溶血素(Hly A)、外膜蛋白(Omps)及丝氨酸蛋白酶(Ahp A)基因,分别设计3对特异性引物。通过3重PCR法对三对基因进行克隆与生物信息学分析。溶血素、外膜蛋白及丝氨酸蛋白酶基因的开放阅读框分别为1 863 bp、1 071 bp及894 bp,分别编码621、357及298个氨基酸。同时,对其氨基酸序列进行系统进化树构建、蛋白理化性质分析、蛋白信号区域和结构区域分析、蛋白二级结构预测、蛋白三级结构预测及蛋白免疫原性分析。本研究对大鲵源致病性嗜水气单胞菌主要毒力基因进行生物信息学分析,为进一步研究嗜水气单胞菌保护性抗原多样性而提供理论基础。

Three pairs of specific primers were designed based on the sequence of hemolysin, outer membrane protein and ex- tracellular serine protease genes of Aeromonas hydrophila published in GenBank.by a multiplex polymerase chain reaction, patho- genic Aeromonas hydrophila from Andrias davidianus were tested for the presence of three virulence genes including the genes en- coding hemolysin, outer membrane protein and extracellular serine protease. Sequence analysis revealed that the hemolysin, outer membrane protein and extracellular serine protease genes were 1 863 bp, 1 071 bp, 894 bp and encoded three putative protein of 621,357,298 amino acids. The gene homology among this strain and others was analyzed by BlastN. We conducted a phylogenetic analysis using the neighbor joining （N J） method： Meanwhile, the related biological information of three coding protein were ana- lyzed, including physical and chemical properties of the protein analysis, protein signal area and structural regional analysis, pro- tein structure prediction, protein immunogenicity analysis and protein tertiary structure prediction. In this assay, the bioinformatic analysis of the major virulence gene of pathogenic Aeromonas hydrophila from Andrias davidianus provided a reference and theoret- ical basis for further study of Aeromonas hydrophila protective antigen diversity and provide a theoretical basis.