[H(+)-ATPase from yeast vacuoles is inhibited by heparin]

Heparin (20-40 micrograms/ml) inhibits by 50% both the ATP hydrolase and the delta pH formation in isolated yeast vacuoles. The GTPase activity is not inhibited under these conditions. ATP prevents this inhibition, being added 10 min before heparin. Heparin suppresses the phosphorylation of vacuolar proteins in vitro. It is supposed that the protein kinase, similar to casein kinase I, participates in the regulation of activity of the vacuolar ATPase.