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Abstract
ATP synthase can be thought of as a complex of two motors — the ATP-driven F1 motor and the proton-driven Fo motor — that rotate in opposite directions. The mechanisms by which rotation and catalysis are coupled in the working enzyme are now being unravelled on a molecular scale.
“All enzymes are beautiful, but ATP synthase is one of the most beautiful as well as one of the most unusual and important” said Paul Boyer1 . ATP synthase — also called the Fo F1 -ATP synthase or Fo F1 -ATPase — synthesizes cellular ATP from ADP and inorganic phosphate (Pi ). The energy for ATP synthesis is provided from downhill H+ (proton) transport along the gradient of ELECTROCHEMICAL POTENTIAL of protons across membranes2 (∆µH+). This potential is built by the electron-transfer chains of respiration or photosynthesis, which pump protons against a gradient (FIG. 1).
ATP Synthase: Structure, Function and Inhibition
Abstract
Oxidative phosphorylation is carried out by five complexes, which are the sites for electron transport and ATP synthesis. Among those, Complex V (also known as the F1F0 ATP Synthase or ATPase) is responsible for the generation of ATP through phosphorylation of ADP by using electrochemical energy generated by proton gradient across the inner membrane of mitochondria. A multi subunit structure that works like a pump functions along the proton gradient across the membranes which not only results in ATP synthesis and breakdown, but also facilitates electron transport. Since ATP is the major energy currency in all living cells, its synthesis and function have widely been studied over the last few decades uncovering several aspects of ATP synthase. This review intends to summarize the structure, function and inhibition of the ATP synthase.