The dismutation of formaldehyde by liver alcohol dehydrogenase.

The results obtained led the authors to the suggestion that Reactions 2 and 4 are catalyzed by liver alcohol dehydrogenase but that Reaction 1 is due to an aldehyde dehydrogenase present in their liver preparation. Because of the inhomogeneity of the enzyme preparation employed, a reinvestigation of this problem with more highly purified enzyme was suggested. With the use of crystalline horse liver alcohol dehydrogenase which was approximately 200 times as active as the preparations previously used, we were able to carry out the reactions described by Kenda1 and Ramanathan. We confirmed their conclusions concerning the nature of the reaction products and the stoichiometry of the reaction. The results obtained with the crystalline enzyme were also in accord with the suggestion of Kendal and Ramanathan (1) that alcohol dehydrogenase itself probably catalyzes Reaction 4 as well as Reaction 2. We could not, however, confirm those observations which had led to the conclusion that different enzymes were required to catalyze Reactions 1 and 4. On the contrary, our findings are consistent with the view that alcohol dehydrogenase is the only enzyme necessary for catalysis of both dismutation reactions of formaldehyde, Reactions 3 and 5.