Seems to be involved in mannitol utilization. Complements an E. coli mtlD deletion mutant. D-mannitol 1-phosphate + NAD(+) = beta-D-fructose 6-phosphate + H(+) + NADH Induced by mannitol. Deletion mutant cannot grow in minimal medium. Mutant fails to persist in the squid. Belongs to the zinc-containing alcohol dehydrogenase family.