An Introduction and Overview to the Section on Electrochemical Gradients Across Membranes

Abstract

Many if not most of the proteins associated with the cytoplasmic membranes of phototrophic bacteria are involved in the generation or the utilization of the proton electrochemical gradient (op). It is now widely recognized that op has a central role in the energy economy of the cell and while a number of unexplained observations remain, it is generally thought that it serves to couple the “energy-generating” reactions of electron transport with the “energy-consuming” reactions of ATP synthesis, nicotinamide nucleotide transhydrogenase and certain kinds of solute translocation. An outstanding problem in biochemistry is to try to understand the mechanisms by which some membrane proteins operate as proton translocators and thus use the energy of op to drive chemical conversions and other transport processes. This section is devoted to work in which this problem is being tackled. Many other contributions to the Symposium, notably the articles of F. Daldal, H.W. Trissl, A.Y. Semenov, and D.B. Knaff should also be consulted for relevant discussions.