Prévost M C, Lesourd M, Arpin M, Vernel F, Mounier J, Hellio R, Sansonetti P J
Station Centrale de Microscopie Electronique, Institut Pasteur, Paris, France.
Infect Immun. 1992 Oct;60(10):4088-99. doi: 10.1128/iai.60.10.4088-4099.1992.
Shigella flexneri causes bacillary dysentery, an invasive disease of colonic epithelial cells in humans. The capacity of bacteria, once they have entered into a cell and escaped the phagocytic vacuole, to spread intracellularly and directly to adjacent cells without further extracellular passage is a key factor in invasion of the epithelial layer. Movement of intracellular bacteria is dependent upon the polymerization of actin; concentration of the formed filaments to one end of the bacterium is associated with initiation of movement. This movement may lead to the formation of a protrusion at the cell surface through which the bacterium passes to an adjacent cell. Development of these protrusions in infected HeLa cells is described, with emphasis on two critical observations. First, initiation of movement is coupled with bacterial division since elongation of the bacterial body is associated with relocalization of the previously uniformly distributed layer of actin to one pole of the bacterium. Second, the actin-bundling protein plastin appears to bundle the actin filaments just posterior to the bacterium, producing an ongoing contraction of the cylindrical actin tail that may be associated with forward movement of the bacterium within the protrusion.
福氏志贺菌可引起细菌性痢疾，这是一种人类结肠上皮细胞的侵袭性疾病。细菌一旦进入细胞并逃离吞噬泡，能够在细胞内扩散并直接传播到相邻细胞而无需进一步通过细胞外途径，这是侵袭上皮层的关键因素。细胞内细菌的移动依赖于肌动蛋白的聚合；形成的细丝集中在细菌的一端与移动的开始有关。这种移动可能导致细胞表面形成一个突起，细菌通过该突起传递到相邻细胞。本文描述了在感染的HeLa细胞中这些突起的形成，重点关注两个关键观察结果。首先，移动的开始与细菌分裂相关，因为菌体的伸长与先前均匀分布的肌动蛋白层重新定位到细菌的一极有关。其次，肌动蛋白束蛋白丝束蛋白似乎在细菌后方将肌动蛋白丝束在一起，产生圆柱形肌动蛋白尾巴的持续收缩，这可能与细菌在突起内的向前移动有关。
