A CheW homologue is required for Myxococcus xanthus fruiting body development, social gliding motility, and fibril biogenesis
A CheW homologue is required for Myxococcus xanthus fruiting body development, social gliding motility, and fibril biogenesis
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DOI：
10.1128/jb.184.20.5654-5660.2002
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发表时间：
2002-10-01
影响因子：
3.2
通讯作者：
Yang, ZM
中科院分区：
文献类型：
--
作者：
Bellenger, K;Ma, XY;Yang, ZM
在具有多组趋化基因的细菌中，同源基因甚至同一操纵子中不同基因的删除可能会导致不同的表型。黄色粘球菌是一种具有多组趋化基因和/或同源物的细菌。之前的研究表明，difA 和 difE 分别编码甲基接受化学感受器蛋白 (MCP) 和 CheA 激酶的同源物，是 M. xanthus 社会滑翔 (S) 运动和发育所必需的。 difA 和 difE 突变体在称为细胞外基质原纤维的细胞表面附属物的生物发生方面也存在缺陷。在这项研究中，我们研究了由 difC（与 difA 和 difE 位于同一基因座的基因）编码的 CheW 同源物的作用。我们发现 difC 突变导致 M. xanthus 发育聚集、孢子形成和 S 运动缺陷。我们证明difC对于野生型细胞凝聚和原纤维生物发生是不可或缺的，但对于菌毛产生却不是必不可少的。我们进一步说明了野生型difC对difC框内缺失的异位互补。 difA、difC 和 difE 突变体的相同表型是一致的，并支持以下假设：Dif 趋化同源物构成调节 M. xanthus 原纤维生物发生和 S 运动的趋化样信号转导途径。
In bacteria with multiple sets of chemotaxis genes, the deletion of homologous genes or even different genes in the same operon can result in disparate phenotypes. Myxococcus xanthus is a bacterium with multiple sets of chemotaxis genes and/or homologues. It was shown previously that difA and difE, encoding homologues of the methyl-accepting chemoreceptor protein (MCP) and the CheA kinase, respectively, are required for M. xanthus social gliding (S) motility and development. Both difA and difE mutants were also defective in the biogenesis of the cell surface appendages known as extracellular matrix fibrils. In this study, we investigated the roles of the CheW homologue encoded by difC, a gene at the same locus as difA and difE. We showed that difC mutations resulted in defects in M. xanthus developmental aggregation, sporulation, and S motility. We demonstrated that difC is indispensable for wild-type cellular cohesion and fibril biogenesis but not for pilus production. We further illustrated the ectopic complementation of a difC in-frame deletion by a wild-type difC. The identical phenotypes of difA, difC, and difE mutants are consistent and supportive of the hypothesis that the Dif chemotaxis homologues constitute a chemotaxis-like signal transduction pathway that regulates M. xanthus fibril biogenesis and S motility.