소 적혈구 막을 DL-palmitoyl carnitine으로 완전 용해한 뒤 calcium phosphate gel 처리후 hydroxyapatite 및 DEAE-cellulose column chromatography로 major sialoglycoprotein을 분리 정제하였으며 정제된 major sialoglycoprotein은 SDS-polyacrylamide gel electrophoresis 에서 순수한 monomer의 형태로 분리되었다. 정제된 major sialoglycoprotein은 glycolipoprotein으로 소량의 인지질과 cholesterol을 함유하고 있었고, sialic acid의 함량이 높았으며 (43%) 아미노산 조성으로 미루어 산성 단백질이었다. 다음 소적혈구 막에 대한 항혈청 및 소적혈구로 흡수된 각각의 항혈청과 정제된 major sialoglycoprotein을 항원으로 하여 crossed-immunoelectrophoresis를 한 결과 상기 glycoprotein은 당 잔기의 일부가 적혈구막 밖으로 노출되어 있었음을 알 수 있었다.
The major glycoprotein of bovine erythrocyte membrane was isolated after the membrane was solubilized with synthetic fatty acyl ester of palmitoyl-DL-carnitine. The major glycoprotein was purified by calcium phosphate gel treatment, hydroxyapatite, and finally DEAE-cellulose column chromatography. The purified major glycoprotein which was completely water-soluble was a glycolipoprotein. It appeared to be homogeneous and monomeric form. There was not any detectable subunit formation when subjected to polyacrylamide gel electrophoresis in the presence of reducing agents or detergents. This major glycoprotein contains high proportion of sialic acid (43%) and acidic amino acids. The results of crossed-immunoelectrophoresis with rabbit antibody to bovine erythrocyte membrane or intact bovine RBC-depleted antibody clearly indicated that the major glycoprotein was located at the outer surface of the membrane.
