Imam A, Laurence D J, Neville A M
Biochem J. 1982 Oct 1;207(1):37-41. doi: 10.1042/bj2070037.
Two individual glycoprotein components from human milk-fat-globule membranes (MFGM) has been purified by selectively extracting the membrane glycoproteins followed by lectin affinity chromatography and gel filtration on Sephadex G-200 in the presence of protein-disaggregating agents. The purified glycoprotein components, termed 'epithelial-membrane glycoprotein' (EMGP-155 and EMGP-39) have estimated molecular weights of 155 000 and 39 000 respectively, and yield a single band under reducing conditions on sodium dodecyl sulphate/polyacrylamide gel. EMGP-155 and EMGP-39 contain 21.0% and 7.0% carbohydrate by weight, with fucose (13.5%, 12.4%), mannose (3.7%, 6.2%), galactose (28.5%, 22.6%), N-acetylglucosamine (17.8%, 7.4%) and sialic acid (36.4%, 51.4%) of the carbohydrate moiety respectively. For both the glycoprotein components, aspartic and glutamic acid and serine are the major amino acid residues.
通过选择性提取人乳脂肪球膜（MFGM）中的膜糖蛋白，然后进行凝集素亲和层析，并在蛋白质解离剂存在的情况下在Sephadex G - 200上进行凝胶过滤，从人乳脂肪球膜中纯化出两种单独的糖蛋白成分。纯化后的糖蛋白成分，称为“上皮膜糖蛋白”（EMGP - 155和EMGP - 39），估计分子量分别为155000和39000，在十二烷基硫酸钠/聚丙烯酰胺凝胶上的还原条件下呈现单一条带。EMGP - 155和EMGP - 39的碳水化合物重量含量分别为21.0%和7.0%，碳水化合物部分中岩藻糖分别占（13.5%，12.4%）、甘露糖分别占（3.7%，6.2%）、半乳糖分别占（28.5%，22.6%）、N - 乙酰葡糖胺分别占（17.8%，7.4%）和唾液酸分别占（36.4%，51.4%）。对于这两种糖蛋白成分，天冬氨酸、谷氨酸和丝氨酸是主要的氨基酸残基。
