Identification and properties of chlamydial polypeptides that bind eucaryotic cell surface components
Identification and properties of chlamydial polypeptides that bind eucaryotic cell surface components
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结合真核细胞表面成分的衣原体多肽的鉴定和特性
DOI：
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发表时间：
1986
影响因子：
3.2
通讯作者：
T. Hackstadt
中科院分区：
文献类型：
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作者：
T. Hackstadt
电印迹技术被用来识别蛋白质的衣原体结合表面放射性碘和Triton X-100溶解的HeLa细胞提取物。两种蛋白质，具有18和32千道尔顿（kDa）的表观分子量，结合HeLa细胞表面成分被确定为沙眼衣原体L2的基本体（EB）。放射性碘化肝素，破坏衣原体与培养细胞的联系，也被这些蛋白质结合。这两种蛋白质在EB上发现，但在非感染性网状体上不存在或存在量减少。全是C。测试的沙眼菌株显示出两种这样的蛋白质，尽管较大蛋白质的表观分子量随血清型而变化，与生物型及其引起的疾病相关。两个鹦鹉热衣原体菌株检查显示只有一个单一的结合蛋白的范围为17至19 kDa。所有的结合蛋白染色强烈，独特的银染十二烷基硫酸钠-聚丙烯酰胺凝胶，并显示出不寻常的敏感性还原剂。32-kDa的蛋白质没有看到，并没有结合125 I-标记的HeLa细胞成分，如果EB溶解在2-巯基乙醇的存在下。然而，32-kDa蛋白不受二硫苏糖醇的影响。与2-巯基乙醇的作用类似，用蛋白酶抑制剂甲苯磺酰基-苯丙氨酸氯甲基酮（TPCK）或甲苯磺酰基-赖氨酸氯甲基酮（TLCK）处理EB后，32 kDa蛋白质不可见。TPCK和TLCK也废除了感染性，如烷化剂N-乙基马来酰亚胺和碘乙酰胺，但后两种药物不影响32 kDa蛋白的外观。用兔抗C.沙眼衣原体L2 EB或来自性病性淋巴肉芽肿患者的血清。这些蛋白质在衣原体与宿主细胞相互作用中的作用尚不清楚，但真核细胞表面成分和肝素的结合，仅在生命周期的感染阶段存在，与疾病相关的血清型之间的变化，以及对还原剂或蛋白酶抑制剂的敏感性，共同表明这些蛋白质在寄生虫-宿主相互作用中的作用。
An electroblotting technique was used to identify proteins of Chlamydia that bound surface-radioiodinated and Triton X-100-solubilized HeLa cell extracts. Two proteins, with apparent molecular masses of 18 and 32 kilodaltons (kDa), that bound HeLa cell surface components were identified on Chlamydia trachomatis L2 elementary bodies (EBs). Radioiodinated heparin, which disrupts chlamydial association with cultured cells, was also bound by these proteins. These two proteins were found on EBs but were absent or were present in reduced amounts on the noninfectious reticulate bodies. All C. trachomatis strains tested displayed two such proteins, although the apparent molecular weight of the larger protein varied with serotype in correlation with biotype and the disease that it caused. Two Chlamydia psittaci strains examined displayed only a single binding protein in the range of 17 to 19 kDa. All of the binding proteins stained intensely and distinctively on silver-stained sodium dodecyl sulfate-polyacrylamide gels and displayed an unusual sensitivity to reducing agents. The 32-kDa protein was not seen and did not bind 125I-labeled HeLa cell components if the EBs were solubilized in the presence of 2-mercaptoethanol. The 32-kDa protein was not affected by dithiothreitol, however. Similar to the effect of 2-mercaptoethanol, the 32-kDa protein was not visualized after treatment of EBs with the protease inhibitors tosyl-phenylalanine chloromethyl ketone (TPCK) or tosyl-lysine chloromethyl ketone (TLCK). TPCK and TLCK also abolished infectivity as did the alkylating agents N-ethylmaleimide and iodoacetamide, yet the latter two agents did not affect the appearance of the 32-kDa protein. These proteins were not detected in immunoblots with either rabbit antisera to C. trachomatis L2 EBs or by serum from a patient with lymphogranuloma venereum. The role of these proteins in the interaction of chlamydiae with host cells is not clear, but the binding of eucaryotic cell surface components and heparin, presence only during the infectious stage of the life cycle, variation between serotypes in correlation with disease, and sensitivity to reducing agents or protease inhibitors, collectively, suggest a role for these proteins in parasite-host interactions.