期刊
JOURNAL OF BIOLOGICAL CHEMISTRY
卷 291, 期 45, 页码 23817-23829出版社
AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
DOI: 10.1074/jbc.M116.753327
关键词
bacterial conjugation; membrane protein; plasmid; protein secretion; protein-protein interaction; type IV secretion
资金
- Canadian Institutes of Health Research (CIHR) [MOP-84239]
- Natural Sciences and Engineering Research Council (NSERC)
- NSERC-CREATE program on the Cellular Dynamics of Macromolecular Complexes (CDMC)
- Bristol Myers Smith Research Chair in Molecular Biology at Universite de Montreal
- Groupe d'etudes des proteines membranaires (GEPROM)
- Canada Foundation for Innovation (CFI)
- Fonds de recherche du Quebec-Sante (FRQ-S)
Gram-negative bacteria use type IV secretion systems (T4SSs) for a variety of macromolecular transport processes that include the exchange of genetic material. The pKM101 plasmid encodes a T4SS similar to the well-studied model systems from Agrobacterium tumefaciens and Brucella suis. Here, we studied the structure and function of TraE, a homolog of VirB8 that is an essential component of all T4SSs. Analysis by X-ray crystallography revealed a structure that is similar to other VirB8 homologs but displayed an altered dimerization interface. The dimerization interface observed in the X-ray structure was corroborated using the bacterial two-hybrid assay, biochemical characterization of the purified protein, and in vivo complementation, demonstrating that there are different modes of dimerization among VirB8 homologs. Analysis of interactions using the bacterial two-hybrid and cross-linking assays showed that TraE and its homologs from Agrobacterium, Brucella, and Helicobacter pylori form heterodimers. They also interact with heterologous VirB10 proteins, indicating a significant degree of plasticity in the protein-protein interactions of VirB8-like proteins. To further assess common features of VirB8-like proteins, we tested a series of small molecules derived from inhibitors of Brucella VirB8 dimerization. These molecules bound to TraE in vitro, docking predicted that they bind to a structurally conserved surface groove of the protein, and some of them inhibited pKM101 plasmid transfer. VirB8-like proteins thus share functionally important sites, and these can be exploited for the design of specific inhibitors of T4SS function.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据