ATP-dependent active ion transport enables cells to regulate their pH value and to control their ion composition. The reverse process, transforming an ion imbalance into chemical energy, drives mitochondrial and chloroplast ATP synthesis. The mediators of these fundamental processes are ion-motive ATPases, highly conserved enzymes that play key roles in cell physiology from bacteria to man. As the first comprehensive overview of this important class of enzymes, this handbook summarizes recent...