band 3

glycoprotein

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Last updated

June 18, 2026

Quick Summary

Band 3 is an abundant glycoprotein that traverses the red cell membrane. It serves as a site for ABO(H) antigens, which are crucial for determining blood type. Glycoproteins are a type of conjugated protein, meaning they are formed by the combination of a protein molecule with a prosthetic group, in this case, oligosaccharides (short chains of sugar molecules). These carbohydrate chains are attached to a polypeptide backbone and are oriented towards the external surface of the red cell membrane, carrying various blood group antigens. The specific sugars and their arrangement determine the antigen's identity.12

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blood group
Chemistry of the blood group substances
An abundant glycoprotein, band 3, is a site of ABO(H) antigens. Another integral membrane glycoprotein, glycophorin A, contains large numbers of sialic acid molecules and MN blood group structures; another, glycophorin B, contains Ss and U antigens.
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An abundant glycoprotein, band 3, is a site of ABO(H) antigens. Another integral membrane glycoprotein, glycophorin A, contains large numbers of sialic acid molecules and MN blood group structures; another, glycophorin B, contains Ss and U antigens.
Read More