[Effect of storage conditions on population variability and activity of Streptomyces recifensis var. lyticus].

The results of the study on survival and variation of Streptomyces recifensis var. lyticus 2435 producing lytic enzymes are presented. The culture was maintained for 2.5 years under a layer of vaseline oil, at a temperature of -20 degrees C and in lyophilized state. It was shown that irrespective of the storage method strain 2435 preserved its viability. However, the most intensive growth was observed in the lyophilized cultures. During the storage the content of the productive colonies characteristic of the morphological type culture in the population decreased while the number of the low active variants increased. Lyophilization of the strain spores in the sucrose-gelatine medium provided insignificant morphological variation of the culture and preservation of the initial level of its lytic activity against a number of test-microbes except S. aureus and M. lysodeikticus. Storage of the culture under vaseline oil and at a temperature of -20 degrees C resulted in lowering of its lytic activity against all the test-microbes used. For long-term maintenance of Streptomyces recifensis var. lyticus 2435 the method of lyophilization in the sucrose-gelatine medium is recommended.