Reactive lysine residues in horse liver alcohol dehydrogenase

Horse liver alcohol dehydrogenase was modified under various conditions with ¹⁴C-labelled formaldehyde in the presence of sodium borohydride. Changes in the enzymatic activity were correlated with incorporated label and modified residues were characterized. It is shown that most of the lysine residues react and that many are affected by the binding of coenzymes and inhibitors to the protein. Reactive residues are reported and possible structural and functional interpretations given.