单核细胞增生李斯特菌SigB调控GadD3的抗酸应激作用  

SigB Regulated GadD3 in Acid Resistance of Listeria monocytogenes

作　　者：王宜 方小伟 刘慧娟 万娇红 郭骞 张钰 田棋 方春 WANG Yi;FANG Xiao-wei;LIU Hui-juan;WAN Jiao-hong;GUO Qian;ZHANG Yu;TIAN Qi;FANG Chun(School of Animal Science,Yangtze University,Jingzhou,Hubei,434025,China)

机构地区：[1]长江大学动物科学学院

出　　处：《动物医学进展》2020年第1期45-49,共5页Progress In Veterinary Medicine

基　　金：农业部畜禽细菌病防治制剂创制重点实验室开放课题(KLPCAAB-2018-05);长江大学大学生创新创业训练计划项目(2018056)

摘　　要：单核细胞增生李斯特菌(简称单增李斯特菌)是一种重要的食源性人兽共患病病原菌,其拥有一系列抗酸应激系统以抵抗酸应激的伤害作用。谷氨酸脱羧酶(GAD)系统是该菌抗酸应激系统重要成员之一,酸应激存活试验表明,GAD系统3个谷氨酸脱羧酶基因对单增李斯特菌抗酸应激能力的贡献依次为gadD2、gadD3和gadD1。为阐明GAD系统抗酸作用调控机制,通过荧光定量PCR、GFP报告基因和免疫印迹结合酸应激存活试验,证实了应激调控因子SigB参与正调控gadD3的转录与表达,但是不影响gadD1和gadD2的表达,进而通过gadD3参与单增李斯特菌的抗酸应激作用。研究结果丰富了单增李斯特菌抗酸应激系统的调控网络,并可为李斯特菌病的防控提供理论依据。Listeria monocytogenes(Lm) is an important foodborne zoonotic pathogen.To encounter the acid stress from environments,host gastrointestinal tract and even the endosome of host cells,Lm proposes a serial of acid resistant systems.The glutamate decarboxylase(GAD) system was one of the major acid resistant systems.Survival assay under pH 2.5 BHI broth showed that among the GAD system,gadD2 made the biggest contribution to Lm survival,followed by gadD3 and gadD1.This study tried to clarify the regulatory mechanisms of anti-acid stress of the GAD system.By conducting quantitative-PCR,GFP reporter gene,Western blot and survival assay under acidic conditions,this study demonstrated that the stress regulator SigB positively regulated the expression of gadD3 to involve in acid resistance of Lm,but had no effect on gadD1 or gadD2.These results enriched the regulatory network of acid resistance of Lm and might provide a little basis for prevention and control of listeriosis.

关 键 词：单核细胞增生李斯特菌 应激调控因子SigB 谷氨酸脱羧酶 抗酸应激 

分 类 号：S852.617[农业科学—基础兽医学] S852.33[农业科学—兽医学]