INTERACTION OF RED CELL MEMBRANE ATPASE WITH CALCIUM

The recent demonstration (Schatzmann, 1966 and 1967), that an (ATP + Mg)-dependent mechanism of Ca-extrusion exists in red cells raises the question of how the splitting of ATP by the membrane may lead to the translocation of the calcium ions. The first step to solve the problem may be the characterization of a Ca-dependent membrane ATPase. Such an enzyme system has already been described in red cell ghosts (Dunham and Glynn, 1961; Wins and Schoffeniels, 1966); although there was some uncertainty about the number of ATPases present in the ghost as well as about their exact role (Wins and Schoffeniels, 1966 and 1967; Laris and Letchworth, 1967), there is little doubt that at least part of the Ca-dependent activity is related to active calcium transport (Schatzmann, 1966). © 1969 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.