Bhattacharyya S N, Lynn W S
J Biol Chem. 1979 Jun 25;254(12):5191-8.
A soluble glycoprotein of Mr = 80,000 has been isolated from lung lavage of patients with alveolar proteinosis and found to contain 5 residues of hydroxyproline, 91 residues of glycine, 3 residues of methionine, 3.8 molecules of sialic acid, 6 molecules of mannose, 5.9 molecules of galactose, 1 molecule of fucose, and 9.1 molecules of glucosamine. Cyanogen bromide (CNBr) treatment of the glycoprotein resulted in four peptides with molecular weights of 36,000, 27,000, 12,000, and 5,000. The chemical compositions of the CNBr peptides indicated the presence of hydroxyproline and high amounts of glycine in all but one of the peptides; two of the four CNBr peptides contained carbohydrate. Limited trypsin digestion of the glycoprotein of Mr = 80,000 resulted in four peptides with molecular weights of 62,000, 36,000, 26,000 and 18,000, the latter being the NH2-terminal peptide of the native glycoprotein molecule. The peptide of Mr = 26,000 was found to be the COOH-terminal peptide.
从肺泡蛋白沉积症患者的肺灌洗物中分离出一种分子量为80,000的可溶性糖蛋白，发现其含有5个羟脯氨酸残基、91个甘氨酸残基、3个甲硫氨酸残基、3.8个唾液酸分子、6个甘露糖分子、5.9个半乳糖分子、1个岩藻糖分子和9.1个葡糖胺分子。用溴化氰（CNBr）处理该糖蛋白产生了四种分子量分别为36,000、27,000、12,000和5,000的肽段。CNBr肽段的化学组成表明，除了其中一个肽段外，其他肽段都含有羟脯氨酸和大量的甘氨酸；四个CNBr肽段中有两个含有碳水化合物。对分子量为80,000的糖蛋白进行有限的胰蛋白酶消化，产生了四种分子量分别为62,000、36,000、26,000和18,000的肽段，后者是天然糖蛋白分子的NH2末端肽段。发现分子量为26,000的肽段是COOH末端肽段。
