<p>Fumarate reductase catalyses the reduction of fumarate to succinate, coupling the reaction to the oxidation of quinol to quinine [<cite idref="PUB00007431"/>]. This reaction is opposite to that catalysed by succinate dehydrogenase. This entry represents the C-terminal domain of fumarate reductase, which is structurally related to the N-terminal domain of dihydropyrimidine dehydrogenase, an enzyme that catalyses the NADPH-dependent conversion of pyrimidines to 5,6-dihydro compounds [<cite idref="PUB00013185"/>].</p>