Nitrate-dependent activation of the Dif signaling pathway of Myxococcus xanthus mediated by a NarX-DifA interspecies chimera.
Nitrate-dependent activation of the Dif signaling pathway of Myxococcus xanthus mediated by a NarX-DifA interspecies chimera.
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NarX-DifA 种间嵌合体介导的黄色粘球菌 Dif 信号通路的硝酸盐依赖性激活。
DOI：
10.1128/jb.187.18.6410-6418.2005
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Yang,Zhaomin
中科院分区：
文献类型：
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作者：
Xu,Qian;Black,WesleyP;Ward,ScottM;Yang,Zhaomin
粘球菌黄原纤维胞外多糖(EPS)对细菌的社会滑动运动和发育是必不可少的，它受Dif趋化性途径的调节。DIFA是一种MCP同源基因，被认为是介导信号输入到Dif途径的。然而，DIFA缺乏一个重要的周质结构域，在经典的化学感受器中，该结构域负责信号感知和启动跨膜信号。为了研究DIFA的信号特性，我们利用大肠杆菌的感觉模块和Fm的信号模块构建了NarX-DIFA(NAFA)嵌合体。XanthusDifA.我们在这里报道了第一个使用来自两个不同系统发育亚群的生物体的基因构建的功能性嵌合信号传导器。当表达时，INM。在硝酸盐存在的情况下，黄花、NAFA恢复了子实体的形成、EPS的产生和S对不同突变体的运动能力。对各种双突变体的研究表明，NAFA需要下游的Dif蛋白才能发挥作用。我们认为，Dif途径的信号输入和DIFA的跨膜信号对于调节EPS产生INM是必不可少的。黄花草。尽管存在明显的结构差异，DIFA似乎与肠道感受器激酶和化学感受器具有相似的跨膜信号机制。
Myxococcus xanthusfibril exopolysaccharide (EPS), essential for the social gliding motility and development of this bacterium, is regulated by the Dif chemotaxis-like pathway. DifA, an MCP homolog, is proposed to mediate signal input to the Dif pathway. However, DifA lacks a prominent periplasmic domain, which in classical chemoreceptors is responsible for signal perception and for initiating transmembrane signaling. To investigate the signaling properties of DifA, we constructed a NarX-DifA (NafA) chimera from the sensory module ofEscherichia coliNarX and the signaling module ofM. xanthusDifA. We report here the first functional chimeric signal transducer constructed using genes from organisms in two different phylogenetic subdivisions. When expressed inM. xanthus, NafA restored fruiting body formation, EPS production, and S-motility todifAmutants in the presence of nitrate. Studies with various double mutants indicate that NafA requires the downstream Dif proteins to function. We propose that signal inputs to the Dif pathway and transmembrane signaling by DifA are essential for the regulation of EPS production inM. xanthus. Despite the apparent structural differences, DifA appears to share similar transmembrane signaling mechanisms with enteric sensor kinases and chemoreceptors.