López-Goñi I, Guzmán-Verri C, Manterola L, Sola-Landa A, Moriyón I, Moreno E
Departamento de Microbiología, Universidad de Navarra, C/lrunlarrea no 1, Pamplona 31008, Spain.
Vet Microbiol. 2002 Dec 20;90(1-4):329-39. doi: 10.1016/s0378-1135(02)00218-3.
The Brucella BvrR/BvrS two-component regulatory system is highly similar to the regulatory and sensory proteins of Sinorhizobium and Agrobacterium necessary for endosymbiosis and pathogenicity in plants, and very similar to a putative system present in the animal pathogen Bartonella. Mutations in the bvrR or bvrS genes hamper the penetration of B. abortus in non-phagocytic cells and impairs intracellular trafficking and virulence. In contrast to virulent Brucella, BvrR/BvrS mutants do not recruit small GTPases of the Rho subfamily required for actin polymerization and penetration to cells. Dysfunction of the BvrR/BvrS system alters the outer membrane permeability, the expression of several group 3 outer membrane proteins and the pattern of lipid A acylation. Constructs of virulent B. abortus chimeras containing heterologous LPS from the bvrS(-) mutant demonstrated an altered permeability to cationic peptides similar to that of the BvrR/BvrS mutants. We hypothesize that the Brucella BvrR/BvrS is a system devoted to the homeostasis of the outer membrane and, therefore in the interface for cell invasion and mounting the required structures for intracellular parasitism.
布鲁氏菌的BvrR/BvrS双组分调节系统与根瘤菌和土壤杆菌中对植物内共生和致病性所必需的调节蛋白及传感蛋白高度相似，且与动物病原体巴尔通体中存在的一个假定系统非常相似。bvrR或bvrS基因的突变会阻碍流产布鲁氏菌在非吞噬细胞中的穿透，并损害细胞内运输和毒力。与有毒力的布鲁氏菌不同，BvrR/BvrS突变体不会募集肌动蛋白聚合和细胞穿透所需的Rho亚家族小GTP酶。BvrR/BvrS系统功能障碍会改变外膜通透性、几种3型外膜蛋白的表达以及脂多糖A酰化模式。含有来自bvrS(-)突变体的异源脂多糖的有毒力流产布鲁氏菌嵌合体构建体表现出与BvrR/BvrS突变体相似的对阳离子肽的通透性改变。我们推测布鲁氏菌的BvrR/BvrS是一个致力于外膜稳态的系统，因此处于细胞入侵界面并为细胞内寄生构建所需结构。
