Schröder Gunnar, Dehio Christoph
Division of Molecular Microbiology, Biozentrum of the University of Basel, CH-4056 Basel, Switzerland.
Trends Microbiol. 2005 Jul;13(7):336-42. doi: 10.1016/j.tim.2005.05.008.
Type IV secretion systems (T4SSs) are transport machineries of Gram-negative bacteria that mediate interbacterial DNA-transfer, and secretion of virulence factors into eukaryotic target cells. A growing number of human pathogenic bacteria use T4SSs for intercellular delivery of effector molecules that modify host cellular functions in favour of the pathogen. Recent advances in studying the molecular mechanisms of Bartonella pathogenesis have provided evidence for the central roles of two distinct T4SSs, VirB/VirD4 and Trw, in the ability of the bacteria to colonize, invade and persist within either vascular endothelial cells or erythrocytes, respectively. The identification of VirB/VirD4-transported substrates and the delineation of their secretion signal have paved the way towards understanding the molecular mechanisms underlying Bartonella-host cell interaction and modulation, as well as the exploitation of this system for engineered substrate delivery into mammalian target cells.
IV型分泌系统（T4SSs）是革兰氏阴性菌的转运机制，介导细菌间DNA转移，并将毒力因子分泌到真核靶细胞中。越来越多的人类致病细菌利用T4SSs将效应分子进行细胞间传递，这些效应分子会改变宿主细胞功能以利于病原体。在研究巴尔通体发病机制的分子机制方面的最新进展为两种不同的T4SSs，即VirB/VirD4和Trw，分别在细菌定殖于血管内皮细胞或红细胞内、侵入并持续存在的能力中所起的核心作用提供了证据。VirB/VirD4转运底物的鉴定及其分泌信号的确定，为理解巴尔通体与宿主细胞相互作用和调节的分子机制，以及利用该系统将工程化底物递送至哺乳动物靶细胞铺平了道路。
