<p>This entry represents the NAD-dependent L-lactate dehydrogenases from bacteria and eukaryotes. This enzyme functions as the final step in anaerobic glycolysis. Although lactate dehydrogenases have in some cases been mistaken for malate dehydrogenases due to the similarity of these two substrates and the apparent ease with which evolution can toggle these activities, critical residues have been identified [<cite idref="PUB00013812"/>] which can discriminate between the two activities.</p><p>This entry represents an active site of the L-lactate dehydrogenase enzyme, and includes a conserved histidine which is essential to the catalytic mechanism.</p>