寡聚核苷酸外切酶Orn通过调控胞内cAMP含量影响铜绿假单胞菌Ⅲ型分泌系统  

Pseudomonas Aeruginosa Oligoribonuclease Affects the TypeⅢSecretion System by Regulating the Intracellular Level of cAMP

作　　者：杨宝鹏 张梦静 靳永新[1] 吴卫辉[1] 潘晓磊 Yang Baopeng;Zhang Mengjing;Jin Yongxin;Wu Weihui;Pan Xiaolei(College of Life Sciences,Key Laboratory of Molecular Microbiology and Technology of Ministry of Education,Nankai University,Tianjin 300071,China)

机构地区：[1]南开大学生命科学学院,分子微生物和技术教育部重点实验室,天津300071

出　　处：《南开大学学报（自然科学版）》2024年第4期107-112,共6页Journal of Nankai University(Natural Sience)

基　　金：国家自然科学基金青年项目(31900115);中国博士后基金资助项目(2020T130323)。

摘　　要：铜绿假单胞菌是重要的条件致病菌,该菌Ⅲ型分泌系统介导的细胞毒性在致病过程中起重要作用.敲除了铜绿假单胞菌的寡聚核苷酸外切酶orn基因,并通过结晶紫染色检测发现了orn敲除菌株(Δorn)对Hela细胞的毒性明显低于野生型.实时定量PCR和western blot实验结果表明,Δorn菌株中Ⅲ型分泌系统结构基因和效应因子的表达水平与野生型菌株相比显著降低.进一步研究发现,Δorn菌株胞内cAMP水平下降,而补加c AMP可以回复细菌的Ⅲ型分泌系统表达水平和细胞毒性.本研究阐明了寡聚核苷酸外切酶调控Ⅲ型分泌系统的机制.Pseudomonas aeruginosa is an opportunistic pathogenic bacterium.The type III secretion system(T3SS)plays an important role in the bacterial pathogenesis.The cytotoxic crystal violet staining method was used to detect the role of oligoribonuclease in regulating the T3SS in P.aeruginosa here.Our results dem-onstrated that mutation of the oligoribonuclease gene(orn)reduced the bacterial cytotoxicity to Hela cells.Quantitative real-time PCR(qRT-PCR)and western blot results revealed defective expression of the T3SS genes in the orn mutant.The intracellular cAMP level was reduced by the mutation of orn was found.Supplementation of cAMP restored the expression levels of the T3SS genes and cytotoxicity of the orn mutant.In combination,an oligoribonuclease-mediated regulatory pathway on the typeⅢsecretion system was elucidated.

关 键 词：铜绿假单胞菌 CAMP 寡聚核苷酸外切酶 Ⅲ型分泌系统 

分 类 号：Q935[生物学—微生物学]