Structure and Function of Transport Proteins That Form Solute Gradients

This chapter focuses on the transport ATPases in detail. Many of the known details of the structure and function of P- and F-type ATPases have been described. While the models developed for the thermodynamic coupling between ATP synthesis (or hydrolysis) and ion transport have conjectural components, they are in general founded on a large amount of experimental data and on the resultant ingenious hypotheses of several investigators. One needs to critically assess these impressive findings and insights in order to understand both what we do and what we do not know about how P- and F-type ATPases catalyze transport. While these general similarities in the structure and function of P- and F-type ATPases have undoubted importance, the differences in the details of their proposed structures and mechanisms of action are striking.