NADH dehydrogenase is the first enzyme within the mitochondrial electron transport chain. It is sited within the inner mitochondrial membrane and consists of 25 polypeptide chains with an FMN prosthetic group. It also contains iron ions which are used in the transfer of high energy electrons along the respiratory chain.
FMN reacts with NADH derived from metabolic redox reactions. FMN is reduced to FMNH2 while NADH is oxidized to NAD. Simultaneously, a proton is pumped across the inner mitochondrial membrane to the intermembranous space.
The proton movement is used to produce 1 molecule of ATP through oxidative phosphorylation.
Ultimately, NADH dehydrogenase transfers a high energy electron to ubiquinone.
Last reviewed 01/2018