[Metabolism of ammonium compounds by Azotobacter chroococcum (author's transl)]

A study on the metabolism of ammonium sulphate, amino acids, peptides, and nutrient broth by Azotobacter chroococcum is presented in this paper. Some of the amino acids studied lowered the pH of the medium while others alkalinized it. After prolonged incubation desamination could be observed. Peptides were hydrolyzed in some cases, although glycyl-glycyl-glycin was not degraded. A certain amount of growth could be observed with peptone as a sole source of carbon. Both nitrogen fixation and growth were stimulated by nutrient broth, but the medium was alkalinized when a higher concentration of nutrient broth was used, due to the production of ammonia.