Fujita S, Cleve H
Biochim Biophys Acta. 1975 Mar 13;382(2):172-80. doi: 10.1016/0005-2736(75)90175-3.
Two minor glycoproteins GP-II and GP-III, were isolated from human erythrocyte membranes and characterized chemically and immunologically. The chemical composition of GP-II and GP-III was similar: GP-II consisted of 81% protein and 19% carbohydrate of which 4.9% was hexose, 5.4% hexosamine and 7.8% sialic acid. GP-III consisted of 76% protein and 24% carbohydrate of which 7.6% was hexose, 7.2% hexosamine and 8.1% sialic acid. The amino acid composition of GP-II and GP-III was also similar. GP-II and GP-III, however, differed in chemical composition from the MN glycoprotein. GP-II and GP-III were associated with the blood group activities Ss, I and A, but not with the MN antigens. GP-III had higher blood group activities per mug of protein than did GP-II. The specific activities for the Ss blood group antigens were increased 3-10-fold by purificantion of GP-III from the aqueous phase of chloroform methanol extracts.
从人红细胞膜中分离出两种次要糖蛋白GP-II和GP-III，并对其进行了化学和免疫学表征。GP-II和GP-III的化学组成相似：GP-II由81%的蛋白质和19%的碳水化合物组成，其中4.9%为己糖，5.4%为己糖胺，7.8%为唾液酸。GP-III由76%的蛋白质和24%的碳水化合物组成，其中7.6%为己糖，7.2%为己糖胺，8.1%为唾液酸。GP-II和GP-III的氨基酸组成也相似。然而，GP-II和GP-III在化学组成上与MN糖蛋白不同。GP-II和GP-III与血型活性Ss、I和A相关，但与MN抗原无关。每微克蛋白质中，GP-III的血型活性高于GP-II。通过从氯仿甲醇提取物的水相中纯化GP-III，Ss血型抗原的比活性提高了3至10倍。
