Structural characteristics and intermolecular organization of human pulmonary-surfactant-associated proteins.
Structural characteristics and intermolecular organization of human pulmonary-surfactant-associated proteins.
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人肺表面活性剂相关蛋白的结构特征和分子间组织。
DOI：
10.1042/bj2400107
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
Sage,H
中科院分区：
文献类型：
--
作者：
Crawford,SW;Mecham,RP;Sage,H
与肺表面活性物质相关的蛋白质之间的结构关系和分子间组织在很大程度上是未知的。我们研究了肺表面活性物质相关蛋白的支气管肺泡灌洗液中获得的肺泡蛋白沉积症的临床综合征的患者。具有32，000 - 36，000和62，000的Mr值的主要蛋白质与存在于这些蛋白质的胶原酶敏感结构域中的分子间二硫键形成硫醇依赖性复合物（Mr大于400，000）。与此相反，其他蛋白质，这是胶原酶不敏感，形成硫醇依赖性低聚物，不共价连接的主要蛋白质。这些蛋白质在正常个体的表面活性剂中的关联是相似的。通过氨基酸分析、二维肽图和细菌-胶原酶消化，32，000 - 36，000-Mr和62，000-Mr的蛋白质几乎相同。CNBr裂解产物的差异表明，较大的蛋白质是由32，000 - 36，000-Mr蛋白质的胶原酶敏感结构域中的非二硫键、共价交联形成的。因此，有证据表明，Mr 32，000 -36，000的脂质相关蛋白质在蛋白质的胶原样N-末端区域中含有二硫键和非二硫键交联，并形成更高的Mr复合物。这种组织结构可能支持肺泡腔中表面活性剂的三维构象。
The structural relationships and intermolecular organization among the proteins associated with pulmonary surfactant are largely unknown. We studied the pulmonary-surfactant-associated proteins in the bronchoalveolar lavage fluid obtained from a patient with the clinical syndrome of alveolar proteinosis. The major proteins with Mr values of 32,000-36,000 and 62,000 formed thiol-dependent complexes (Mr greater than 400,000) with intermolecular disulphide bonds present in the collgenase-sensitive domains of these proteins. In contrast, other proteins, which were collagenase-insensitive, formed thiol-dependent oligomers that were not covalently linked to the major proteins. The associations of these proteins in the surfactant of a normal individual were similar. By amino acid analysis, two-dimensional peptide mapping and bacterial-collagenase digestion the 32,000-36,000-Mr and 62,000-Mr proteins were nearly identical. Differences in CNBr cleavage products suggested that the larger of the proteins was formed by non-disulphide, covalent, cross-links in the collagenase-sensitive domains of the 32,000-36,000-Mr proteins. Thus the evidence suggested that the lipid-associated proteins of Mr 32,000-36, 000 contained both disulphide and non-disulphide cross-links in the collagen-like N-terminal region of the proteins and form higher-Mr complexes. This organization may support the three-dimensional conformation of surfactant in the alveolar space.