Gabridge M G, Taylor-Robinson D
Infect Immun. 1979 Jul;25(1):455-9. doi: 10.1128/iai.25.1.455-459.1979.
The biochemical nature of the neuraminidase-sensitive Mycoplasma pneumoniae receptor site on human lung fibroblast cells was studied. Purified, mixed sialoglycolipid (ganglioside) preparations from human and bovine tissues did not bind to M. pneumoniae organisms and block their subsequent attachment to fibroblasts. Fibroblasts incubated for 24 h in sialoglycolipid solutions to increase the ganglioside content of their membranes did not show increased pathogen attachment when later incubated with mycoplasmas. HeLa cells grown in the presence of sodium butyrate to increase GM3 ganglioside levels likewise did not have significantly increased uptake of M. pneumoniae organisms. Treatment of fibroblasts with enzymes indicated that the mycoplasma receptor site is trypsin and papain resistant but Pronase sensitive. Pronase digests of fibroblast membranes contained a product(s) which combined with M. pneumoniae cellls and cosedimented with them during centrifugation. Glycoproteins, purified from fibroblast membranes by a lithium diiodosalicylate solubilization technique, similarly bound to M. pneumoniae organisms. Collectively, these data suggest that the major component of the M. pneumoniae receptor site is a sialoglycoprotein with little or no lipid.
对人肺成纤维细胞上神经氨酸酶敏感的肺炎支原体受体位点的生化性质进行了研究。从人和牛组织中纯化得到的混合唾液酸糖脂（神经节苷脂）制剂不会与肺炎支原体结合，也不会阻止其随后附着于成纤维细胞。在唾液酸糖脂溶液中孵育24小时以增加其细胞膜神经节苷脂含量的成纤维细胞，在随后与支原体孵育时，并未表现出病原体附着增加。在丁酸钠存在下生长以增加GM3神经节苷脂水平的HeLa细胞同样没有显著增加肺炎支原体的摄取。用酶处理成纤维细胞表明，支原体受体位点对胰蛋白酶和木瓜蛋白酶有抗性，但对链霉蛋白酶敏感。成纤维细胞膜的链霉蛋白酶消化产物中含有一种能与肺炎支原体细胞结合并在离心过程中与之共沉淀的物质。通过二碘水杨酸锂溶解技术从成纤维细胞膜中纯化得到的糖蛋白同样能与肺炎支原体结合。总体而言，这些数据表明，肺炎支原体受体位点的主要成分是一种唾液酸糖蛋白，几乎不含脂质或不含脂质。
