摘要: EVIDENCE for the earlier suggested1 participation of a flavin compound in pyruvic acid oxidation by Bacterium Delbruckii has been obtained procedure similar to that used Warburg and Christian2 remove prosthetic group (flavin-adenin dinucleotide) from amino-acid oxidase. Phosphate extracts derived lactic bacteria were repeatedly precipitated with 50 per cent ammonium sulphate at pH. 3 1–2° C. By this treatment protein fraction was obtained, which on addition thiamin (vitamin B1) pyrophosphate only1, did not catalyse oxidation, but so together flavin-adenin dinucleotide, kindly supplied me Prof. O. Warburg.