Effect of diamide on proton translocation by the mitochondrial H+-ATPase.

Treatment of sonic submitochondrial particles with the bifunctional thiol reagent, diamide, results in an enhancement of proton conductivity and ATPase activity, which is reversed by the reducing agent dithiothreitol, is suppressed by Fo inhibitors like oligomycin and is absent in particles that are deprived of peripheral Fo polypeptides. The effect of diamide is apparently due to oxidation of dithiols to disulfides in peripheral polypeptide(s) of Fo.