These enzymes are members of the larger class of aldehyde dehydrogenases.

Oxygen is used to remove an amine group from a molecule, resulting in the corresponding aldehyde and ammonia.

An aldol reaction, for example, is inherently diastereoselective if the aldehyde is enantiopure, the resulting aldol adduct is diastereomerically and enantiomerically pure.

When an α hydrogen is present (as is the case when the carbonyl is an aldehyde), it will tautomerize to the corresponding enone.