ATP-DEPENDENT H-PUMP ACTIVITY IN INVERTED VESICLES OF METHANOSARCINA-MAZEI GO1 AND CHARACTERIZATION OF MEMBRANE ATPASE()

ATP-dependent H+-pump activity was found in inverted vesicles of Metha nosarcina mazei Go1 by using acridine orange as a fluorescent probe. T he H+-pump activity specifically required both Mg and sulfite ions, bu t azide, an inhibitor of F0F1-ATPase, did not inhibit the activity. Th e membranes prepared from M. mazei also had an Mg-ATPase activity, and at least the presence of vacuolar-type ATPase was detected.