The lactic acid oxidase of the mycobacteria

Abstract

Although most of the mycobacteria can oxidize lactate, the rate of oxidation varies considerably from one species to another (see An aerobic dehydrogenase catalysing the overall re- action (1) was originally extracted from Mycobacterium phlei The enzyme was specific for the oxidation of L-lactate and did not oxidize pyruvate or acetate. CH3. CH(OH) . C02H + 02 = CH3 . CO2H + C02 + H20. (1) Anaerobically, with methylene blue as hydrogen acceptor, the crude enzyme preparation oxidized lactate to pyruvate. Since partially purified enzyme preparations contained flavin-adenine dinucleotide (FAD), it seemed that the enzyme might be a flavoprotein (F) operating as follows: CHR3. CH(OH) . CO2H + F =CH3.CO.CO2H+FH2, (2) FH2+02=F+H202,