[Causes of degeneration of cultures of Thermoactinomyces vulgaris].

Passage of cultures of Thermoactinomyces vulgaris on a peptone-maize medium causes their degeneration which is manifested in an impaired formation of the sporulating aerial mycelium, and in an increase of the amount of non-germinating spores in populations. The process of degeneration depends on the following conditions: the location of the inoculated material (spores) on the surface of a solid growth medium, which is determined by the technique of inoculation; the state of the spores (degeneration is accelerated if the spores were not activated with low temperatures); the quality of the growth medium.