Membrane systems in which foreign proton pumps are incorporated.

Detailed information about the role of the proton-motive force in solute transport has often been obtained from studies in model systems such as membrane vesicles. For many bacteria, such studies have been hampered by the lack of a good proton-motive force generating system in these model systems. Recently this problem has been solved by the development of procedures to incorporate foreign proton pumps in membrane vesicles derived from bacteria. This improved model system has been used for studies on the role of the proton-motive force in solute transport in fermentative bacteria and yeasts. Important applications can be found in studies of many energy-transducing systems in membranes which lack a suitable proton pump.