The role of Escherichia coli type III secretion system 2 chaperone protein ygeG in pathogenesis of avian pathogenic Escherichia coli
The role of Escherichia coli type III secretion system 2 chaperone protein ygeG in pathogenesis of avian pathogenic Escherichia coli
复制标题
大肠杆菌III型分泌系统2伴侣蛋白ygeG在禽致病性大肠杆菌发病机制中的作用。
DOI：
10.1016/j.rvsc.2021.09.011
复制
发表时间：
2021-09-14
影响因子：
2.4
通讯作者：
Qi, Kezong
中科院分区：
文献类型：
--
作者：
Yin, Lei;Li, Qianwen;Qi, Kezong
大肠杆菌III型分泌系统2（ETT 2）存在于大多数大肠杆菌中。大肠杆菌菌株，携带一个29.9-kb的ETT 2致病岛（派），并参与禽致病性大肠杆菌（APEC）的毒力。伴侣蛋白是细菌分泌系统所必需的，但ETT 2伴侣蛋白的功能尚未确定。结果表明，ygeG与已鉴定的细菌伴侣蛋白具有序列同源性，并含有四肽重复序列（TPR）。为了研究ygeG在APEC ETT 2中的作用，构建了ygeG突变株和互补株并进行了表征。灭活ygeG对APEC细胞生长无影响，但能显著促进DF-1细胞生物膜形成、粘附和侵袭，特别是在SPF鸡血清中的存活能力。对ygeG在鸡感染模型中的作用的分析表明，ygeG的缺失增加了细菌的毒力。比较APEC野生型和ygeG突变体的RNA测序（RNA-Seq）分析表明，编码生物膜形成、外膜蛋白、菌毛基因和毒力效应蛋白基因的多个基因受ygeG调控。这些结果揭示了ygeG作为伴侣蛋白影响APEC的毒力和致病性的作用。
The Escherichia coli type III secretion system 2 (ETT2) is present in most E. coli strains, carries a 29.9-kb ETT2 pathogenicity island (PAI) and is involved in the virulence of avian pathogenic Escherichia coli (APEC). A chaperone protein is essential for the bacterial secretion system, but the function of the ETT2 chaperone protein has not been determined. This study showed that ygeG had sequence homology with the identified bacterial chaperone protein and it possessed tetratri-copeptide repeats (TPR) containing protein. To investigate the role of ygeG in the ETT2 of APEC, ygeG mutant and complemented strains were constructed and characterized. Inactivation of ygeG had no effect on APEC growth, but significantly promoted biofilm formation, and the adherence to and invasion of DF-1 cells, especially the survival abilities in specific-pathogen-free (SPF) chicken sera serum. Analysis of the role of ygeG in chicken infection models revealed that the deletion of ygeG increased bacterial virulence. RNA Sequencing (RNA-Seq) analyses comparing the APEC wild type and the ygeG mutant indicated that multiple genes encoding biofilm formation, outer membrane proteins, fimbrial genes and virulence effector protein genes were regulated by ygeG. These results revealed the role of ygeG as a chaperone protein that affected the virulence and pathogenicity of APEC.