L-lactate dehydrogenase-like enzymesMembers of this subfamily are tetrameric NAD-dependent 2-hydroxycarboxylate dehydrogenases including LDHs, L-2-hydroxyisocaproate dehydrogenases (L-HicDH), and LDH-like malate dehydrogenases (MDH). Dehydrogenases catalyze the conversion of carbonyl compounds to alcohols or amino acids. LDHs catalyze the last step of glycolysis in which pyruvate is converted to L-lactate. Vertebrate LDHs are non-allosteric, but some bacterial LDHs are activated by an allosteric effector such as fructose-1,6-bisphosphate. L-HicDH catalyzes the conversion of a variety of 2-oxo carboxylic acids with medium-sized aliphatic or aromatic side chains. MDH is one of the key enzymes in the citric acid cycle, facilitating both the conversion of malate to oxaloacetate and replenishing levels of oxalacetate by reductive carboxylation of pyruvate. The LDH-like subfamily is part of the NAD(P)-binding Rossmann fold superfamily, which includes a wide variety of protein families including the NAD(P)-binding domains of alcohol dehydrogenases, tyrosine-dependent oxidoreductases, glyceraldehyde-3-phosphate dehydrogenases, formate/glycerate dehydrogenases, siroheme synthases, 6-phosphogluconate dehydrogenases, aminoacid dehydrogenases, repressor rex, and NAD-binding potassium channel domains, among others.