Active on hydroxypyruvate and glyoxylate. (R)-glycerate + NAD(+) = 3-hydroxypyruvate + H(+) + NADH Optimum pH is 6.8. Optimum temperature is 45 degrees Celsius. One-carbon metabolism; formaldehyde assimilation via serine pathway. Homodimer. By methanol. Belongs to the D-isomer specific 2-hydroxyacid dehydrogenase family.