Separation of two adenosine triphosphatases from erythrocyte membrane

Abstract

Post et al. (1960), Dunham and Glynn (1961), and Whittam (1962) have presented evidence that ouabain-sensitive adenosine triphosphatase (ATPase) in erythrocytes participates in the active transport of sodium and potassium ion in erythrocytes. In previous papers, our collaborators and some of the present authors ( M. Nakao et al., 1960a, 1960b, and 1961) reported on the reversible shape transformation of erythrocytes depending upon ATP level inside the cells. These results may indicate the presence of an ATPase which controls shape transformation of erythrocytes. Onishi (1962) suggested the presence of actin-like and myosin-like proteins in erythrocytes in his preliminary experiments. Furthermore, evidence that ouabain does inhibit the ATPase activity partially but not completely ( Dunham and Glynn 1961), strongly suggests the presence of a different ATPase (i.e. ouabain-insensitive ATPase) other than the ouabain-sensitive ATPase. However, it has not been proved whether the ouabain-sensitive and ouabain-insensitive components of the ATPase are two separate enzymes or not ( Dunham and Glynn 1961). In the present paper, separation of two ATPases from erythrocyte membranes and some of their properties will be presented.