Human erythrocytes were treated with various hydrophobic arylisothiocyanates under conditions which favor modification of distinct proteinaceous nucleophiles. The morphological appearance of phenylisothiocyanate-treated cells was discoid and membrane-bound hydrolases (human acetylcholinesterase, sheep phospholipase A2) were fully active following membrane modification. Noncharged hydrophobic arylisothiocyanates, including phenylisothiocyanate, beta-naphthylisothiocyanate and heterobifunctional azidoarylisothiocyanates inhibited [35S]-sulfate efflux irreversibly. Protection against modification-induced inhibition of sulfate transport was attained by the simultaneous presence of the specific reversible anion transport inhibitor 4,4prime-dinitrostilbene-2,2prime-disulfonate. Selective protection of a functionally relevant domain of band 3 is concluded to occur based on the above-derived information.
Functional evidence for distinct interaction of hydrophobic arylisothiocyanates with the erythrocyte anion transport protein
CACCIOLA, Santa Olga;
1984-01-01
Abstract
Human erythrocytes were treated with various hydrophobic arylisothiocyanates under conditions which favor modification of distinct proteinaceous nucleophiles. The morphological appearance of phenylisothiocyanate-treated cells was discoid and membrane-bound hydrolases (human acetylcholinesterase, sheep phospholipase A2) were fully active following membrane modification. Noncharged hydrophobic arylisothiocyanates, including phenylisothiocyanate, beta-naphthylisothiocyanate and heterobifunctional azidoarylisothiocyanates inhibited [35S]-sulfate efflux irreversibly. Protection against modification-induced inhibition of sulfate transport was attained by the simultaneous presence of the specific reversible anion transport inhibitor 4,4prime-dinitrostilbene-2,2prime-disulfonate. Selective protection of a functionally relevant domain of band 3 is concluded to occur based on the above-derived information.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.