杀鱼爱德华氏菌质膜蛋白酶HtpX致病作用与受调控研究  

The pathogenicity and regulation of the plasma membrane protease HtpX in Edwardsiella piscicida

作　　者：吴清娟 许嘉芮 方清建 黄惠琴[2,4] 胡永华 WU QingJuan;XU JiaRui;FANG QingJian;HUANG HuiQin;HU YongHua(Zhanjiang Experimental Station,Chinese Academy of Tropical Agricultural Sciences,Zhanjiang 524013,China;Institute of Tropical Bioscience and Biotechnology,Chinese Academy of Tropical Agricultural Sciences&Key Laboratory of Biology and Genetic Resources of Tropical Crops of Hainan Province,Hainan Institute for Tropical Agricultural Resources,Haikou 571101,China;College of Marine Biology and Aquatics,Hainan University,Haikou 570228,China;Hainan Provincial Key Laboratory for Functional Components Research and Utilization of Marine Bioresources,Haikou 571101,China)

机构地区：[1]中国热带农业科学院湛江实验站,湛江524013 [2]中国热带农业科学院热带生物技术研究所,海南热带农业资源研究院海南省热带农业生物资源保护与利用重点实验室,海口571101 [3]海南大学海洋生物与水产学院,海口570228 [4]海南省海洋生物资源功能性成分研究与利用重点实验室,海口571101

出　　处：《中国科学：生命科学》2024年第10期2003-2014,共12页Scientia Sinica(Vitae)

基　　金：国家自然科学基金(批准号:32273184);中央级公益性科研院所基本科研业务费项目(批准号:1630102024003)资助。

摘　　要：杀鱼爱德华氏菌是一种典型的胞内病原菌,能够感染鱼类等多种水产养殖动物,对全球水产养殖业构成巨大威胁.当前对该菌致病机制的认识仍不清晰.质膜蛋白酶HtpX被认为与蛋白酶FtsH一起参与膜蛋白的质量控制,受包膜应激感应调控因子CpxR调控.FtsH和CpxR在杀鱼爱德华氏菌致病过程中发挥重要作用,但HtpX的作用未知.本研究通过构建htpX敲除株发现,杀鱼爱德华氏菌HtpX与细菌耐高温和妥布霉素等环境压力密切相关,发现HtpX参与了细菌运动性和抗宿主血清作用;致病性实验表明,HtpX在细菌对上皮细胞黏附、巨噬细胞内的存活与增殖以及对宿主全局性毒力等方面发挥着重要作用.此外,发现htpX启动子的活性受CpxR的正调控,并可能依赖于CpxR磷酸化水平.本研究为杀鱼爱德华氏菌的生物学特性及致病机制提供了新的见解.Edwardsiella piscicida is a typical intracellular pathogen with the potential to infect a variety of fish species,posing a huge threat to the global aquaculture industry and causing substantial losses to the economy.The pathogenesis of this bacterium is still poorly understood.The plasma membrane protease HtpX is considered to be involved in the quality control of membrane proteins together with the protease FtsH,and the transcription of htpX is regulated by CpxR.FtsH and CpxR play an important role in the virulence of E.piscicida.However,the effect of HtpX in E.piscicida is still unknown.In this study,by constructing htpX knockout strains,we found that HtpX in E.piscicida was closely related to bacterial resistance to high temperature and tobramycin,and also found that HtpX was involved in the bacterial motility and host serum resistance.The pathogenicity experiments showed that HtpX played an important role in the adherence of bacteria to epithelial cells,survival and proliferation in macrophages,and global virulence to the host.In addition,htpX was positively regulated by CpxR and dependent on the level of CpxR phosphorylation.This study provides new insights into the biology and pathogenic mechanisms of E.piscicida.

关 键 词：杀鱼爱德华氏菌 质膜蛋白酶HtpX 致病性 调控机制 CpxR 

分 类 号：S941.42[农业科学—水产养殖]