Does sphingomyelin inhibit the erythrocyte anion transport system?
The anion transport protein of the human erythrocyte membrane, band 3, was incorporated into unilamellar sphingomyelin vesicles. The vesicles showed a rapid sulfate efflux which could be inhibited by specific inhibitors of the erythrocyte anion transport system. All band 3 molecules contributing to the inhibitor-sensitive flux component were arranged 'right-side-out'. The turnover number of the transport protein for sulfate transport was virtually identical to that in phosphatidylcholine bilayers and around 6 times larger than in human erythrocyte membranes. Thus, in contrast to other claims, sphingomyelin does not inhibit the erythrocyte anion transport system.
Scheuring
U
U
Max-Planck-Institut für Biophysik, Frankfurt am Main, FRG.
Haase
W
W
Schubert
D
D
D001457:Anion Exchange Protein 1, Erythrocyte / Q000187:drug effects*; D006801:Humans; D007700:Kinetics; D008081:Liposomes; D008854:Microscopy, Electron; D011510:Proteolipids; D013109:Sphingomyelins / Q000494:pharmacology*
D001457:Anion Exchange Protein 1, Erythrocyte; D008081:Liposomes; D011510:Proteolipids; D013109:Sphingomyelins; C020485:proteoliposomes