[Physiologo-biochemical features of the growth and development of Propionibacterium shermanii in egg albumin].

Propionibacterium shermanii was shown to be able of growing in such an unusual substrate as egg albumen. Incubation of the bacterium in egg albumen results in complete utilization of free carbohydrates in this substrate and accumulation in it of such bacterial metabolites as vitamins B2 and B12, free amino acids, bacterial protein, acetic and propionic acids which favour conservation of egg albumen. The bacterium does not possess proteolytic activity and does not utilize albumen; in the conditions of nitrogen deficiency, it can utilize free amino acids in the substrate. The growth of P. shermanii in egg albumen is stimulated by the addition of ammonium sulfate in combination with potassium phosphate or ammonium phosphate to the substrate. These substances change the direction of propionic fermentation toward the accumulation of propionic acid; at the same time, the content of glutamine, asparagine, alanine, methionine, cysteine and other free amino acids increases in the substrate.