Mechanism and structure of the bacterial type IV secretion systems.
Mechanism and structure of the bacterial type IV secretion systems.
复制标题
DOI：
10.1016/j.bbamcr.2013.12.019
复制
发表时间：
2014-08
影响因子：
5.1
通讯作者：
Gonzalez-Rivera, Christian
中科院分区：
文献类型：
--
作者：
Christie, Peter J.;Whitaker, Neal;Gonzalez-Rivera, Christian
细菌IV型分泌系统(T4SS)通常通过一种依赖于细胞间直接接触的机制将DNA和蛋白质底物转移到细菌或真核细胞的靶细胞。T4SS包括两个大的亚家族，共轭系统和效应器移位器。接合系统介导细菌间DNA转移，并负责抗生素耐药性基因和毒力决定因素在临床环境中的快速传播。许多革兰氏阴性细菌利用效应器转运子将数百种毒力蛋白运送到真核细胞，以调节感染过程中的不同生理过程。最近，在定义T4SS机子单元和大机子组件的结构方面取得了相当大的进展。此外，底物转位序列的性质和辅助蛋白在底物与转位通道对接中的作用也得到了阐明。确定了一条通过农杆菌VIRB/VirD4系统的DNA易位途径，细胞内(DNA配体、ATP能量)和细胞外(噬菌体结合)信号都激活了依赖于IV型的易位。最后，系统发育研究揭示了T4SS的进化和分布，对不同系统的互补结构-功能研究已经确定了在致病环境中为新功能量身定做的适应。本文综述了我们对这些迷人机器的结构和作用机制的理解的最新进展，重点介绍了根癌农杆菌VIRB/VirD4 T4SS及其相关的接合系统。
The bacterial type IV secretion systems (T4SSs) translocate DNA and protein substrates to bacterial or eukaryotic target cells generally by a mechanism dependent on direct cell-to-cell contact. The T4SSs encompass two large subfamilies, the conjugation systems and the effector translocators. The conjugation systems mediate interbacterial DNA transfer and are responsible for the rapid dissemination of antibiotic resistance genes and virulence determinants in clinical settings. The effector translocators are used by many Gram-negative bacterial pathogens for delivery of potentially hundreds of virulence proteins to eukaryotic cells for modulation of different physiological processes during infection. Recently, there has been considerable progress in defining the structures of T4SS machine subunits and large machine subassemblies. Additionally, the nature of substrate translocation sequences and the contributions of accessory proteins to substrate docking with the translocation channel have been elucidated. A DNA translocation route through the Agrobacterium tumefaciens VirB/VirD4 system was defined, and both intracellular (DNA ligand, ATP energy) and extracellular (phage binding) signals were shown to activate type IV-dependent translocation. Finally, phylogenetic studies have shed light on the evolution and distribution of T4SSs, and complementary structure-function studies of diverse systems have identified adaptations tailored for novel functions in pathogenic settings. This review summarizes the recent progress in our understanding of the architecture and mechanism of action of these fascinating machines, with emphasis on the ‘archetypal’ A. tumefaciens VirB/VirD4 T4SS and related conjugation systems.
登录
查看更多内容
影响因子：
6.7
作者：
Carey KL;Newton HJ;Lührmann A;Roy CR
通讯作者：
Roy CR
影响因子：
3.2
作者：
Banta, Lois M.;Kerr, Jennifer E.;Christie, Peter J.
通讯作者：
Christie, Peter J.
影响因子：
2.9
作者：
Baron, Christian
通讯作者：
Baron, Christian
影响因子：
3.6
作者：
Atmakuri, K;Ding, ZY;Christie, PJ
通讯作者：
Christie, PJ
影响因子：
3.6
作者：
Atmakuri, K;Cascales, E;Christie, PJ
通讯作者：
Christie, PJ