aguA基因缺失对嗜水气单胞菌致病性的影响  

Deletion of the aguA gene affects pathogenicity of Aeromonas hydrophila

作　　者：赵东康 Rachit PENGLEE 车金远 易欣鑫 邱超达 鲍宝龙[1,2] ZHAO Dongkang;Rachit PENGLEE;CHE Jinyuan;YI Xinxin;QIU Chaoda;BAO Baolong(Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources,Ministry of Education,Shanghai Ocean University,Shanghai 201306,China;National Demonstration Center for Experimental Fisheries Science Education,Shanghai Ocean University,Shanghai 201306,China)

机构地区：[1]上海海洋大学水产种质资源发掘与利用教育部重点实验室,上海201306 [2]上海海洋大学水产科学国家级实验教学示范中心,上海201306

出　　处：《上海海洋大学学报》2023年第3期449-459,共11页Journal of Shanghai Ocean University

基　　金：福建省科委区域重点项目(2020R1022009)。

摘　　要：嗜水气单胞菌(Aeromonas hydrophila)是水环境常见的病原体,具有较强致病性。在本研究中,首次敲除了嗜水气单胞菌aguA基因,通过转录组分析发现aguA基因敲除后细菌的黏附、致病、胺代谢等生物过程下降。通过qRT-PCR进一步验证发现10个黏附基因、9个发病基因和8个胺代谢基因的mRNA表达水平明显下降;此外,转录组水平分析结合qRT-PCR验证发现Ⅵ型分泌系统基因、Ⅱ型分泌系统基因、鞭毛合成相关基因、菌毛合成相关基因、溶血基因、Ⅰ型分泌系统基因、肠毒素基因、RTX基因等毒力基因的RNA表达水平也出现下调。与野生菌株(WT)相比,aguA敲除株(ΔaguA)感染金鱼的致病力降低了86.6%,且aguA敲除株生物膜形成能力降低了16.6%。以上结果显示,aguA基因与嗜水气单胞菌的致病性密切相关。Aeromonas hydrophila is a common pathogen in water environment and has strong pathogenicity.In this study,the gene aguA of A.hydrophila was knocked out for the first time.Transcriptome analysis and qRT-PCR indicated that the knockout of aguA down-regulated the bacterial adhesion process,pathogenic process,amine metabolism process and etc.In addition,typeⅥsecretion system genes,typeⅡsecretion system genes,flagella synthesis-related genes,fimbriae synthesis-related genes,hemolysis genes,typeⅠsecretion system genes,enterotoxin genes,and RTX genes were also down-regulated at the transcriptome level.qRT-PCR showed that most of these genes were significantly down-regulated.Compared with the wild strain,the pathogenicity of A.hydrophila aguA-knocked-out strain infected grass goldfish was reduced by 86.6%through infection experiment in vivo,and it was found that the biofilm formation ability of the aguA-knocked-out strain was reduced by 16.6%.The above results show that aguA gene is closely related to the pathogenicity of A.hydrophila.

关 键 词：嗜水气单胞菌 胍丁胺脱亚胺酶 毒性 致病性 

分 类 号：S917[农业科学—水产科学]