Popov V L, Yu X j, Walker D H
Department of Pathology, WHO Collaborating Center for Tropical Diseases, Galveston, Texas 77555-0609, USA.
Microb Pathog. 2000 Feb;28(2):71-80. doi: 10.1006/mpat.1999.0327.
The immunodominant 120 kDa protein (p120) of Ehrlichia chaffeensis was demonstrated to be exposed on the surface of purified whole ehrlichial cells examined by immunoelectron microscopy with a rabbit antibody against a portion of the domain containing tandem repeat units. In the intracellular location, the 120 kDa protein was detected by immunoelectron microscopy in the outer membrane of the cell wall of dense-core forms of the ehrlichiae in infected canine macrophage-like cells and as a component of the intramorular fibrillary matrix. No 120 kDa protein was detected in the cell wall of ehrlichial reticulate cells. Recombinant Escherichia coli with a plasmid containing the entire 120 kDa protein gene, but no bacteria with non-recombinant plasmid, attached to the surface of HeLa cells as visualized by electron microscopy. Some of the recombinant 120 kDa protein expressing E. coli invaded the HeLa cells as determined by gentamicin protection assays and by intravacuolar localization ultrastructurally.
用针对含有串联重复单元的结构域部分的兔抗体，通过免疫电子显微镜检查发现，恰菲埃立克体的免疫显性120 kDa蛋白（p120）暴露于纯化的完整埃立克体细胞表面。在细胞内定位中，通过免疫电子显微镜在感染犬巨噬细胞样细胞中埃立克体致密核心形式的细胞壁外膜中检测到120 kDa蛋白，并且其作为细胞内纤维状基质的一个组成部分。在埃立克体网状细胞的细胞壁中未检测到120 kDa蛋白。电子显微镜观察显示，带有含有完整120 kDa蛋白基因质粒的重组大肠杆菌附着于HeLa细胞表面，而带有非重组质粒的细菌则未出现这种情况。通过庆大霉素保护试验和超微结构的液泡内定位确定，一些表达重组120 kDa蛋白的大肠杆菌侵入了HeLa细胞。
