This family contains related reductases/dehydrogenases.

• 3-hydroxyisobutyrate dehydrogenase (EC: 1.1.1.31) catalyzes the NAD-dependent, reversible oxidation of 3-hydroxbutyrate to methylmalonate [PMID:2647728]. In eukaryotes, it is a homodimeric mitochondrial protein involved in valine catabolism. In Pseudomonas aeruginosa [PMID:1339433] (gene mmsB), it is involved in the distal valine metabolic pathway.
• 2-hydroxy-3-oxopropionate reductase (EC: 1.1.1.60) catalyses the NAP(P)H dependent reduction of 2-hydroxy-3-oxopropionate (tartronate semialdehyde) to D-glycerate.
• 6-phosphogluconate dehydrogenase (EC: 1.1.1.44) catalyzes the NADP-dependent decarboxylation of 6-phosphogluconate to D-ribulose 5-phosphate and CO₂.