H-ATPASE OF YEAST VACUOLES IS INHIBITED BY HEPARIN()

Heparin at concentrations 20-40 mu g/ml inhibits Delta pH formation on the membrane and by 50% of ATPase activity in isolated vacuoles of th e yeast Saccharomyces cerevisiae. GTPase activity in vacuoles is insen sitive to heparin. The inhibitory effect of heparin is prevented by AT P added 5-10 min before introducing heparin. Heparin suppresses phosph orylation of vacuolar proteins. It is assumed that casein kinase I par ticipates in the regulation of vacuolar ATPase activity.