EVALUATION OF EXPERIMENTALLY-INDUCED ENZYMATIC ALTERATIONS ON THE ERYTHROCYTE-MEMBRANE BY USE OF ALCIAN BLUE

The binding of the polycationic dye alcian blue to erythrocytes is investigated at pH 6 and pH 3 after treatment with neuraminidase and proteolytic enzymes. The portion of the dye bound by membrane-negative charge-carriers, as well as by hydrophobic interactions with mainly membrane protein compounds, is calculated. It is demonstrated that not only the sialic acid, as the main negative charge domain, but also proteins are interacting with the dyestuff. Proteolytically split membrane fragments contain a considerable amount of alcian blue that cannot be associated with the estimated sialic acid content.