NADH, Succinate and Malate Oxidation in Corn Mitochondrial

state 4 and state 3 conditions was studied with corn shoot mitochondria. Comparisons were made.' usin malate and succinate as'-substrates. The inhibitors, rotenone, amvtal. antimycin A andcyanide, inhibited oxidation of NADH in state 3 but rotenone and amytal did not inhibit oxidation in state 4. The inhibition by antimycin A was partially overcome by the presence of cytochrome c. The results indicate the presence of alternative pathways available for NADH oxidation depending onthe metabolic condition of the mitochondria. Under state 4 conditions, NADH oxidation bypasses -the amytal -and rotenone sensitive sites but under state 3 conditions