On the life of Ralstonia solanacearum, a destructive bacterial plant pathogen
On the life of Ralstonia solanacearum, a destructive bacterial plant pathogen
复制标题
DOI：
--
复制
发表时间：
2010
期刊：
影响因子：
--
通讯作者：
B. Álvarez;E. Biosca;M. López
中科院分区：
文献类型：
--
作者：
B. Álvarez;E. Biosca;M. López
青枯雷尔氏菌（Ralstonia solanacearum）是一种广泛分布的植物病原细菌，其引起的枯萎病对许多重要的经济作物和农作物具有致命的影响。它属于β-变形菌，被认为是一个“物种复合体”。这种土壤和水传播的细菌进入植物根部，通过木质部繁殖，破坏宿主并返回环境。它具有入侵和定殖寄主植物的有效致病性决定因素，但也表现出在恶劣条件下生存的成功策略。因此，在宿主植物细胞的存在下，调节级联激活细胞壁降解酶的分泌和编码III型分泌系统的组分的过敏反应和致病性基因簇。一旦进入植物组织，高密度的病原体增加了毒力基因的表达和胞外多糖的产生，胞外多糖是主要的致病性决定因素。这些基因是由密度依赖性调控网络参与控制的群体感应系统。在破坏植物后，细菌可以通过不同的生存形式在环境中持续存在，直到与新的宿主接触。
Ralstonia solanacearum is a relevant and widespread phytopathogenic bacterium that causes a wilt disease with deadly effects on many economically important crops and ornamentals. It belongs to the β-proteobacteria and is considered a “species complex”. This soil and water borne bacterium enters the plant roots, multiplies through the xylem, collapses the host and returns to the environment. It has effective pathogenicity determinants to invade and colonize host plants but, also exhibits successful strategies for survival in harsh conditions. Thus, in the presence of host plant cells, a regulatory cascade activates secretion of cell wall-degrading enzymes and the cluster of hypersensitive reaction and pathogenicity genes encoding components of a type III secretion system. Once in the plant tissues, high densities of the pathogen increase expression of virulence genes and production of exopolysaccharide, the main pathogenicity determinant. These genes are controlled by a density-dependent regulatory network taking part in a quorum sensing system. After destroying the plant, the bacterium can persist in the environment through diverse survival forms until contact with a new host.