An activation domain of plasmid R1 TraI protein delineates stages of gene transfer initiation.
An activation domain of plasmid R1 TraI protein delineates stages of gene transfer initiation.
复制标题
DOI：
10.1111/j.1365-2958.2011.07872.x
复制
发表时间：
2011-12
影响因子：
3.6
通讯作者：
Zechner EL
中科院分区：
文献类型：
--
作者：
Lang S;Kirchberger PC;Gruber CJ;Redzej A;Raffl S;Zellnig G;Zangger K;Zechner EL
细菌接合是IV型分泌的一种形式，其将蛋白质和DNA转运到受体细胞。特定的噬菌体利用这些系统的接合性皮利和跨细胞被膜的蛋白质机制来入侵细菌细胞。被噬菌体R17感染需要F样皮利和偶联蛋白TraD，其门控分泌通道的胞质入口。在这里，我们调查的作用，TraD在R17核蛋白的摄取，并找到平行的分泌机制。需要IncFII质粒R1的松弛体。质粒oriT，TraD和TraI的N-末端992个残基内的新激活结构域的三元复合物有助于涉及TraI的松弛酶相关性质，蛋白质相互作用和TraD ATP酶的关键机制。TraI的解旋酶相关活性是不稳定的。这些研究结果区分第一次特定的蛋白质结构域和复合物的过程中的IV型起始途径的细胞外信号到不同的激活阶段。该研究还提供了对噬菌体及其利用的质粒的进化相互作用的见解。相关质粒F独立于TraI适应于R17。因此，噬菌体抗性的选择不仅驱动TraA菌毛蛋白的变异，而且以质粒特异性方式使TraD及其结合伴侣多样化。
Bacterial conjugation is a form of type IV secretion that transports protein and DNA to recipient cells. Specific bacteriophage exploit the conjugative pili and cell envelope spanning protein machinery of these systems to invade bacterial cells. Infection by phage R17 requires F-like pili and coupling protein TraD, which gates the cytoplasmic entrance of the secretion channel. Here we investigate the role of TraD in R17 nucleoprotein uptake and find parallels to secretion mechanisms. The relaxosome of IncFII plasmid R1 is required. A ternary complex of plasmid oriT, TraD and a novel activation domain within the N-terminal 992 residues of TraI contributes a key mechanism involving relaxase-associated properties of TraI, protein interaction and the TraD ATPase. Helicase-associated activities of TraI are dispensable. These findings distinguish for the first time specific protein domains and complexes that process extracellular signals into distinct activation stages in the type IV initiation pathway. The study also provided insights into the evolutionary interplay of phage and the plasmids they exploit. Related plasmid F adapted to R17 independently of TraI. It follows that selection for phage resistance drives not only variation in TraA pilins but diversifies TraD and its binding partners in a plasmid-specific manner.
登录
查看更多内容
影响因子：
3.2
作者：
Beranek, A;Zettl, M;Koraimann, G
通讯作者：
Koraimann, G
影响因子：
3.6
作者：
Maneewannakul, K;Kathir, P;IppenIhler, K
通讯作者：
IppenIhler, K
影响因子：
3.7
作者：
KRAHN, PM;PARANCHYCH, W;OCALLAGH.RJ
通讯作者：
OCALLAGH.RJ
影响因子：
3.2
作者：
Dostal, Lubomir;Schildbach, Joel F.
通讯作者：
Schildbach, Joel F.
影响因子：
3.2
作者：
BAYER, M;EFERL, R;HOGENAUER, G
通讯作者：
HOGENAUER, G