111 Bioluminescence analysis and numerical evaluation of ATP-synthesis by native and reconstituted membranes containing bacterial ATP-synthase

Abstract

ATP-synthase is a large membrane protein complex, which plays a key role in the energy metabolism of most organisms. It consists of at least eight types of subunits and can be isolated and purified from several organisms, e.g. bacteria. The enzyme couples two reversible reactions: vectorial proton transport through a membrane and synthesis of the energy rich molecule ATP. Both can be investigated with vesicles from native membranes or with reconstituted liposomes from purified ATPsynthase. The analysis is complicated because ATP-synthase catalyzes ATP-synthesis as well as ATP-hydrolysis. Furthermore the ATP level of membrane samples is influenced by adenylate kinase activities of other enzymes.