5I97

Structural analysis and inhibition of TraE from the pKM101 type IV secretion system

5I97 の概要

• エントリーDOI: 10.2210/pdb5i97/pdb
• 分子名称: Conjugal transfer protein (2 entities in total)
• 機能のキーワード: bacterial secretion, type iv secretion, virb, protein transport
• 由来する生物種: Escherichia coli
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 75272.42

構造登録者

Casu, B.,Sygusch, J.,Baron, C. (登録日: 2016-02-19, 公開日: 2016-09-28, 最終更新日: 2023-09-27)

主引用文献

Casu, B.,Smart, J.,Hancock, M.A.,Smith, M.,Sygusch, J.,Baron, C.
Structural Analysis and Inhibition of TraE from the pKM101 Type IV Secretion System.
J.Biol.Chem., 291:23817-23829, 2016

PubMed Abstract: 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.

PubMed: 27634044
DOI: 10.1074/jbc.M116.753327

実験手法

X-RAY DIFFRACTION (2.441 Å)