Wilharm Gottfried, Lehmann Verena, Krauss Kristina, Lehnert Beatrix, Richter Susanna, Ruckdeschel Klaus, Heesemann Jürgen, Trülzsch Konrad
Bakteriologie, Max von Pettenkofer-Institut, Pettenkoferstrasse 9a, D-80336 Munich, Germany.
Infect Immun. 2004 Jul;72(7):4004-9. doi: 10.1128/IAI.72.7.4004-4009.2004.
The flagellum is believed to be the common ancestor of all type III secretion systems (TTSSs). In Yersinia enterocolitica, expression of the flagellar TTSS and the Ysc (Yop secretion) TTSS are inversely regulated. We therefore hypothesized that the Ysc TTSS may adopt flagellar motor components in order to use the pathogenicity-related translocon in a drill-like manner. As a prerequisite for this hypothesis, we first tested a requirement for the proton motive force by both systems using the protonophore carbonyl cyanide m-chlorophenylhydrazone (CCCP). Motility as well as type III-dependent secretion of Yop proteins was inhibited by CCCP. We deleted motAB, which resulted in an immotile phenotype. This mutant, however, secreted amounts of Yops to the supernatant comparable to those of the wild type. Translocation of Yops into host cells was also not affected by the motAB deletion. Virulence of the mutant was comparable to that of the wild type in the mouse oral infection model. Thus, the hypothesis that the Ysc TTSS might adopt flagellar motor components was not confirmed. The finding that, in addition to consumption of ATP, Ysc TTSS requires the proton motive force is discussed.
鞭毛被认为是所有III型分泌系统（TTSSs）的共同祖先。在小肠结肠炎耶尔森菌中，鞭毛TTSS和Ysc（Yop分泌）TTSS的表达受到反向调控。因此，我们推测Ysc TTSS可能采用鞭毛运动组件，以便以类似钻孔的方式使用与致病性相关的转位因子。作为该假设的前提，我们首先使用质子载体羰基氰化物间氯苯腙（CCCP）测试了这两种系统对质子动力的需求。CCCP抑制了运动性以及Yop蛋白的III型依赖性分泌。我们删除了motAB，这导致了无运动能力的表型。然而，该突变体向上清液中分泌的Yop量与野生型相当。Yop向宿主细胞的转位也不受motAB缺失的影响。在小鼠口服感染模型中，该突变体的毒力与野生型相当。因此，Ysc TTSS可能采用鞭毛运动组件这一假设未得到证实。此外，除了消耗ATP外，Ysc TTSS还需要质子动力这一发现也进行了讨论。
