热休克蛋白100家族ClpL对猪链球菌2型应激和致病性的影响  

Contributions of HSP100/ClpL to the stress tolerance and pathogenicity of Streptococcus suis type 2

作　　者：祝昊丹[1] 王锐 周俊明[1] 王丹丹[1] 胡屹屹[1] 倪艳秀[1] 李彬[1] ZHU Haodan;WANG Rui;ZHOU Junming;WANG Dandan;HU Yiyi;NI Yanxiu;LI Bin(Institute of Veterinary Medicine,Jiangsu Academy of Agricultural Sciences,Nanjing 210014,Jiangsu,China)

机构地区：[1]江苏省农业科学院兽医研究所,江苏南京210014

出　　处：《微生物学通报》2025年第2期668-678,共11页Microbiology China

基　　金：国家自然科学基金(31302114);河北省省级科技计划(21322401D)。

摘　　要：【背景】酪蛋白水解蛋白酶L(caseinolytic protease L,ClpL)是热休克蛋白100(heat shock protein 100,HSP100)家族成员,参与多种细胞内生物学过程包括应激耐受反应、长期存活、毒力和抗生素抗性等,在病原菌的致病过程中发挥重要作用。【目的】阐明HSP100/ClpL对猪链球菌2型(Streptococcus suis type 2)强毒株的应激耐受和毒力的影响。【方法】利用温敏自杀质粒pSET4s构建了SsClpL基因缺失株ΔclpL;利用大肠杆菌-猪链球菌穿梭质粒pSET2构建了互补株CΔclpL;比较亲本株SS2-1、ΔclpL和CΔclpL在各种应激环境(高温、氧化性应激和酸应激)和血液中的生存能力;利用小鼠感染模型和体内竞争试验评价clpL缺失前后细菌的毒力变化。【结果】clpL缺失后,SS2在各种应激环境中的生存能力明显减弱;同时在猪全血中的存活能力也显著降低;对BALB/c小鼠的致病力有所降低,在体内的定殖能力明显降低。【结论】SsClpL与猪链球菌的应激耐受和致病性密切相关。[Background]Caseinolytic protease L(ClpL),a member of the heat shock protein(HSP)100 family,is involved in various cellular processes,such as the stress tolerance response,long-term survival,virulence,and antibiotic resistance,playing important roles in the infection of pathogenic bacteria.[Objective]The present study aimed to elucidate the contributions of HSP100/ClpL to the stress tolerance and virulence of Streptococcus suis type 2.[Methods]We used the thermo-sensitive suicide vector pSET4s and the Escherichia coli-Streptococcus suis shuttle vector pSET2 to construct an isogenic clpL mutant strain(ΔclpL)and a complemented strain(CΔclpL),respectively.We then compared the growth characteristics of the wild-type strain SS2-1,ΔclpL,and CΔclpL under various stress conditions(including high temperature,acidic environment,and oxidative stress)in vitro and in pig whole blood.Furthermore,we employed a mouse model of infection and challenged mice with SS2-1+ΔclpL or SS2-1+CΔclpL to compare the virulence of SS2-1,ΔclpL,and CΔclpL.[Results]The mutant strainΔclpL showed reduced survival rates under stress conditions and in pig whole blood.In addition,it showed attenuated virulence in BalB/C mice.Furthermore,ΔclpL had significantly lower colonization ability than SS2-1 in mice.[Conclusion]The data indicate that the SsClpL is involved in the stress response and pathogenicity of SS2.

关 键 词：猪链球菌2型 热休克蛋白100家族ClpL 应激耐受 致病性 

分 类 号：S852.61[农业科学—基础兽医学]