Alcohol dehydrogenase of animal tissues

Abstract

Various methods of prep. of the liver alcohol dehydrogenase and its properties were descr. By using suitable preparations it was shown that cozymase and cozymase factor were essential components of the system. According to the treatment, preps. were obtained which contained no cozymase but had enough coenzyme factor (precipitation with ammonium sulphate) and vice versa (precipitation with acetone). The alcohol dehydrogenase in the preps. remained unaltered over a period of mos. Under certain exptl. conditions acetaldehyde was obtained quantitatively as the reaction product of alc. oxidation. The probability of other courses of alc. oxidation was discussed. The alc. dehydrogenase in the preps. did not react directly with O; the presence of carriers (methylene blue, pyocyanine) being necessary. The reaction with O2 was markedly accelerated by the addition of cytochrome oxidase preps. Ethyl, propyl, methyl and amyl alcs. were oxidized by the liver alc. dehydrogenase preps. Negative results were obtained with glycerol, [alpha]-glycerophosphate and saligenin. Iodoacetate had little effect upon the animal alc. dehydrogenase. The enzyme was not sensitive to cyanide. Evidence was presented for the non-identity of the liver alc. dehydrogenase and aldehyde mutase.