Cation-sensitive ATPase from gills of the salt water mussel, Mytilus edulis

Abstract

1. 1. Membranes from gills of Mytilus edulis contain an ATPase which is stimulated by the univalent cations, Na +, K +, Rb +, Li +, and, to a lesser extent Cs +. 2. 2. Activity requires Mg 2+ and is insensitive to ouabain, vanadate, and SH inhibitors. 3. 3. Stimulation of activity by the uncouplers, FCCP, ∗ dinitrophenol and nonyldinitrophenol, suggests that the preparation is at least partially vesicular and that it is best described as a univalent cation-proton ATPase. 4. 4. It is likely that the ATPase plays a role in the ability of this organism to concentrate solutes, such as amino acids, from surrounding seawater.