7株鳗鲡致病性气单胞菌毒力基因胞外产物及其活性比较  

Analysis of virulence genes,extracellular products and activities among seven Aeromonas strains isolated from eels

作　　者：熊静[1,2,3] 赖晓健[1,2,3] 余钦[1] 郭松林[1,2] 徐继松[1,2,3] 黄文树[1,4] 

机构地区：[1]集美大学水产学院,厦门361021 [2]鳗鲡现代产业技术教育部工程研究中心,厦门361021 [3]集美大学水域环境与渔业资源监测中心,厦门361021 [4]福建省海洋生物资源开发利用协同创新中心,厦门361021

出　　处：《华中农业大学学报》2017年第1期76-85,共10页Journal of Huazhong Agricultural University

基　　金：国家自然科学基金项目(31172438和U1205123);福建省科技厅重点项目(2013Y0089);福建省教育厅项目(JA12195;JA15260);厦门市科技局项目(3502Z20133015);鳗鲡现代产业技术教育部工程研究中心开放基金项目(ZK2013004;RE201304;RE201306;RE201307);校预研启动基金项目(ZQ2012007)

摘　　要：为探讨致病性气单胞菌的致病力与其胞外产物和毒力因子之间的关系,联合利用PCR、SDS-PAGE、平板扩散及分子进化等方法对7株鳗源气单胞菌的胞外毒力因子进行比较研究。结果显示,该7株致病菌所含有的胞外毒力基因(hly、aer、ast、act、alt、ahpA、epr和exu)在种类和数量上差异显著,其中hly可能是鳗源气单胞菌重要的致病因子;不同致病菌的胞外蛋白在种类和数量上都存在差异,其中分子质量约为50.7ku的蛋白,其分泌量高且在鳗源气单胞致病菌中较保守;该7株致病菌胞外产物均具有溶血、酪蛋白酶和卵磷脂酶活性,胞外产物活性与毒力基因的分布一致;胞外毒素基因hly和ahpA具有较高的属间保守性,而exu则具有较好的种间特异性。To clarify the roles of virulence genes and extracellular products played in the pathogenicity of Aeromonas,PCR amplification, SDS-PAGE electrophoresis, plate diffusion and phylogenetic analysis were used in this study to investigate into the differences of extracellular virulence factors from 7 trains of pathogenic Aeromonas isolated from diseased eels. The results showed that these 7 strains were significantly different in the amount and types of virulence genes （hly ,aer,ast, act ,alt, ahpA, epr and exu）,of which hly may be mainly responsible for the pathogenicity of Aeromonas. The extracellular products of the 7 Aeromonas strains were different in both the amount and types,but 5 strains contained an-50.7 ku protein which might be the product of aer gene. All the 7 Aeromonas strains exhibited hemolytic activity, protease activity of casein and lecithin in all the different growth phases tested, and their detectable activities were consistent with expression of virulence genes. Genes hly and ahp were highly conserved between genus,while exu was specific even within species.

关 键 词：气单胞菌 胞外产物 生物活性 毒力基因 

分 类 号：S917.1[农业科学—水产科学]