Fo-F1 particles are mainly formed of
polypeptides. The F1-particle contains 5 types of polypeptides, with the composition-ratio—3α:3β:1δ:1γ:1ε. The Fo has the 1a:2b:12c composition. Together they form a rotary motor. As the protons bind to the subunits of the Fo domains, they cause parts of it to rotate. This rotation is propagated by a 'camshaft' to the F1 domain. ADP and Pi (inorganic phosphate) bind spontaneously to the three β subunits of the F1 domain, so that every time it goes through a 120° rotation ATP is released (rotational catalysis). The Fo domains sits within the membrane, spanning the phospholipid bilayer, while the F1 domain extends into the cytosol of the cell to facilitate the use of newly synthesized ATP. The Bovine Mitochondrial F1-ATPase Complexed with the
inhibitor protein If1 is commonly cited in the relevant literature. Examples of its use may be found in many cellular fundamental metabolic activities such as
acidosis and
alkalosis and respiratory gas exchange. The o in the Fo stands for
oligomycin, because oligomycin is able to inhibit its function. == N-ATPase ==