Deibel C, Dersch P, Ebel F
Institut für Medizinische Mikrobiologie, Justus-Liebig-Universität, Giessen, Germany.
Int J Med Microbiol. 2001 Mar;290(8):683-91. doi: 10.1016/S1438-4221(01)80007-2.
The outer membrane protein intimin plays a crucial role in the attaching and effacing process employed by different enteropathogens to colonize the epithelial surface of their hosts. In this study we have characterized the C-terminal binding domain of intimin from the Shiga toxin-producing Escherichia coli strain 413/89-1, that belongs to the beta-subtype of intimins. We found that a fusion of this domain to the maltose-binding protein binds efficiently to both the translocated intimin receptor (Tir) and the surface of uninfected eukaryotic host cells. In contrast, no such binding was observed with the full-length protein localized on the bacterial surface. As the C-terminal domain of intimin and the full-length protein differ in their binding activity, we suggest that the intimin-binding domain might be controlled by the N-terminal portion of the molecule to prevent unproductive interactions with molecules in the lumen of the gut.
外膜蛋白紧密素在不同肠道病原体用于定殖于宿主上皮表面的黏附和损伤过程中起着关键作用。在本研究中，我们对产志贺毒素大肠杆菌菌株413/89 - 1的紧密素C端结合结构域进行了表征，该菌株属于紧密素的β亚型。我们发现，该结构域与麦芽糖结合蛋白的融合体可有效结合转位紧密素受体（Tir）和未感染的真核宿主细胞表面。相比之下，位于细菌表面的全长蛋白未观察到这种结合。由于紧密素的C端结构域和全长蛋白在结合活性上存在差异，我们认为紧密素结合结构域可能受分子N端部分的调控，以防止与肠腔内分子发生无效相互作用。
