Lactaldehyde is an intermediate in the methylglyoxal metabolic pathway. Methylglyoxal is converted to D-lactaldehyde by glycerol dehydrogenase (gldA). Lactaldehyde is then oxidized to lactic acid by aldehyde dehydrogenase. Lactaldehyde exists in several forms: in open-chain form and as cyclic hemiacetal; in solution and in crystal forms; as monome...