茄科雷尔氏菌的蛋白分泌系统及其特征

Versatile and Features of Secretion Systems from Pathogenic Bacteria Ralstonia solanacearum

茄科雷尔氏菌利用自身的分泌系统能向胞外分泌上百种蛋白,其中Ⅱ型和Ⅲ型分泌系统通过不同机制将分泌蛋白靶定到胞外或宿主细胞,是决定茄科雷尔氏菌对宿主产生致病性的主要因素。其中Ⅲ型分泌系统不依赖Sec信号转导系统但必须依赖于宿主细胞的识别激活,并在病原菌对宿主细胞的特异性识别和细菌在宿主细胞的生长增殖中发挥功能。到目前为止,已经从茄科雷尔氏菌的GMI1000株系中鉴定出两类在宿主细胞中存在靶标,并由Ⅲ型分泌系统分泌的效应蛋白Pop2和Gala蛋白家族。主要就茄科雷尔氏菌Ⅲ型分泌系统的基本特征以及效应蛋白及其宿主靶标的相互作用进行综述。

Hundreds of proteins are secreted extracellularly in Ralstonia solanacearum through several specialized protein secretion systems.Key factors to pathogenicity are the type Ⅱ and type Ⅲ secretion systems,both of which are able to export large repertoires of pathogenicity effectors with distinct mechanism.The type Ⅲ secretion system play an important role in host plant recognition as well as in bacteria proliferation,the whole process depend on host microbe interaction and recognition,however,it is Sec signal transduction pathway independent.To date,two groups of type Ⅲ secretion system effectors with host plant targets,named Pop2 and Gala family proteins,have been identified in R.solanacearum strain GMI1000.This review mainly focus on the secretion systems of R.solanacearum and the interaction between host plant target and the type Ⅲ effectors proteins such as Pop2 and Gala family proteins.