Evolutionary diversification of the RomR protein of the invasive deltaproteobacterium, Bdellovibrio bacteriovorus.
Evolutionary diversification of the RomR protein of the invasive deltaproteobacterium, Bdellovibrio bacteriovorus.
复制标题
入侵性δ变形菌、噬菌蛭弧菌的 RomR 蛋白的进化多样化。
DOI：
10.1038/s41598-019-41263-5
复制
发表时间：
2019
影响因子：
4.6
通讯作者：
Lowry RC
中科院分区：
文献类型：
--
作者：
Lowry RC
弓形细菌弧菌是一种掠食性三角洲变形杆菌，它遇到具有滑行或游泳运动的革兰氏阴性猎物细菌，然后能够通过IVa型菌毛依赖机制入侵这些猎物细胞。其他三角洲变形菌的运动控制（毛或滑翔），如群体猎食黏液球菌，使用反应调节蛋白RomRMx（在细胞两极之间动态定位）和GTPase MglAMx（以前被假设为frzm化学感觉系统和滑动或毛运动装置之间的接口）来产生受调节的双向运动。相比之下,B。细菌捕食是孤独的捕食者和猎物之间更奇特的相遇；捕食者总是通过有毛的、无鞭毛的极点接触，包括MglABd，但没有Frz系统。在这项新的研究中，在捕食性生长过程中，显微镜下跟踪荧光romrbd表明，与它们相反，它不会动态地重新定位。xanthusprotein;而是在成长事件中扮演可能的角色。此外，转录起始分析、位点定向诱变和细菌双杂交相互作用研究表明，在这种单独狩猎的细菌中，romrbd激活（通过受体结构域磷酸化）的进化丧失，证明了其在群体狩猎中运动的双极性作用的差异。黄原和进一步的进化可能区分单独的和群体捕食者。
Bdellovibrio bacteriovorusis a predatory deltaproteobacterium that encounters individual Gram-negative prey bacteria with gliding or swimming motility, and then is able to invade such prey cells via type IVa pilus-dependent mechanisms. Movement control (pili or gliding) in other deltaproteobacteria, such as the pack huntingMyxococcus xanthus, uses a response regulator protein, RomRMx(which dynamically relocalises between the cell poles) and a GTPase, MglAMx, previously postulated as an interface between the FrzMxchemosensory system and gliding or pilus-motility apparatus, to produce regulated bidirectional motility. In contrast,B. bacteriovoruspredation is a more singular encounter between a lone predator and prey; contact is always via the piliated, non-flagellar pole of the predator, involving MglABd, but no Frz system. In this new study, tracking fluorescent RomRBdmicroscopically during predatory growth shows that it does not dynamically relocalise, in contrast to theM. xanthusprotein; instead having possible roles in growth events. Furthermore, transcriptional start analysis, site-directed mutagenesis and bacterial two-hybrid interaction studies, indicate an evolutionary loss of RomRBdactivation (via receiver domain phosphorylation) in this lone hunting bacterium, demonstrating divergence from its bipolar role in motility in pack-huntingM. xanthusand further evolution that may differentiate lone from pack predators.