Weise M J, Ingram V M
J Biol Chem. 1976 Nov 10;251(21):6667-73.
Membrane vesicles produced when chick erythroid cells are disrupted by nitrogen cavitation were isolated by centrifugation in a sucrose step gradient and purified on a linear sucrose gradient. Sodium dodecyl sulfate-polyacrylamide gel analysis of isolated membranes shows eight to ten proteins and four to five glycoproteins. Membranes must be prepared with protease inhibitors, otherwise an endogenous activity degrades high molecular weight polypeptide components. Red cells from several stages of development (5- and 17-day embryos and adult chickens) all appear to have the same major embrane proteins. However, primitive erythroid cells from 5-day embryos lack a Mr = 40,000 glycoprotein that is present in definitive erythrocytes from 17-day embryos and from adult chickens; erythrocytes from young chicks show a decrease in the amount of a glycoprotein of Mr = 50,000. Lactoperoxidase-catalyzed iodination of intact 5-day embryonic red cells detects three surface components which comigrate with the membrane glycoproteins on sodium dodecyl sulfate polyacrylamide gels.
当鸡红细胞通过氮空化作用被破坏时产生的膜泡，通过在蔗糖阶梯梯度中离心进行分离，并在线性蔗糖梯度上进行纯化。对分离出的膜进行十二烷基硫酸钠-聚丙烯酰胺凝胶分析，显示有八到十种蛋白质和四到五种糖蛋白。必须用蛋白酶抑制剂制备膜，否则内源性活性会降解高分子量多肽成分。来自几个发育阶段（5天和17天胚胎以及成年鸡）的红细胞似乎都具有相同的主要膜蛋白。然而，5天胚胎的原始红细胞缺乏一种分子量为40,000的糖蛋白，该糖蛋白存在于17天胚胎和成年鸡的成熟红细胞中；幼雏的红细胞显示分子量为50,000的糖蛋白数量减少。用乳过氧化物酶催化完整的5天胚胎红细胞碘化，可检测到三种表面成分，它们在十二烷基硫酸钠聚丙烯酰胺凝胶上与膜糖蛋白迁移率相同。
