Identification of the central quorum sensing regulator of virulence in the enteric phytopathogen, Erwinia carotovora:: the VirR repressor
Identification of the central quorum sensing regulator of virulence in the enteric phytopathogen, Erwinia carotovora:: the VirR repressor
复制标题
DOI：
10.1111/j.1365-2958.2005.04939.x
复制
发表时间：
2006-01-01
影响因子：
3.6
通讯作者：
Salmond, GPC
中科院分区：
文献类型：
--
作者：
Burr, T;Barnard, AML;Salmond, GPC
在革兰氏阴性植物病原菌中，胡萝卜软腐欧文氏菌（Erwinia carotovora ssp.）黑胫病菌（Eca）的毒力取决于N-（3-氧代己酰基）-L-高丝氨酸内酯（OHHL）群体感应（QS）信号的产生。这项工作确定了欧文氏菌QS和毒力之间难以捉摸的“缺失环节”。我们已经确定并表征了一种新的调节剂的毒力，VirR，在Eca和显示，一个virR突变完全恢复毒力因子的生产Eca突变体无法合成OHHL。virR突变的这种作用转化为毒力恢复到野生型水平，从而提供了证据表明，VirR的作用，以防止在低细胞密度的毒力因子的生产。我们还表明，在Eca中，毒力基因的转录是由OHHL控制的，这种控制是通过VirR的作用来实现的。我们还表明，VirR的调节途径是存在的，并在黑脚和软腐欧文氏菌的物种的功能。
In the Gram-negative phytopathogen, Erwinia carotovora ssp. atroseptica (Eca) virulence depends on the production of a N-(3-oxohexanoyl)-L-homoserine lactone (OHHL) quorum sensing (QS) signal. This work identifies the elusive 'missing link' between QS and virulence in Erwinia. We have identified and characterized a novel regulator of virulence, VirR, in Eca and show that a virR mutation completely restores virulence factor production to an Eca mutant unable to synthesize OHHL. This effect of the virR mutation translates to a restoration of virulence to wild-type levels and thus provides evidence that VirR acts to prevent the production of virulence factors at low cell density. We also show that, in Eca, transcription of virulence genes is controlled by OHHL and that this control is effected through the action of VirR. We also demonstrate that the VirR regulatory pathway is present and functional in both blackleg and soft rotting species of Erwinia.