[Preparation and characteristics of protoplasts of Streptomyces kanamyceticus]. / Poluchenie i kharakteristika protoplastov shtamma Streptomyces kanamyceticus.

To prepare actively regenerating protoplasts of S. kanamyceticus, the influence of the conditions of the mycelium cultivation, the culture age, lytic conditions, composition of the regeneration medium, the procedure of the culture inoculation to the regeneration medium and other parameters were studied. The study resulted in development of optimal conditions for preparation of S. kanamyceticus protoplasts in a number of 1.10(9) protoplasts per ml. The cultivation on the ST medium with 10 to 15% sucrose and addition of glycine up to 1% for 30 hours (the stationary growth phase) followed by treatment of the culture with lysozyme in an amount of 2 mg/ml for 1 hour at 32 degrees C provided preparation of up to 100% of actively regenerating protoplasts free of mycelium fragments. The size of the protoplasts increased up to 1.5 micron against the usually observed size of 0.7 to 1.0 micron with using modified lyzing buffer with 20% of sucrose according to the method recommended for S. erythreus. However, 50 to 70% of the protoplasts had point of linear regions in the cell walls, which suggested that spheroplasts were mainly forming and the phenomenon was associated with the characteristic properties of the strain cell wall structure.

[Cytological study of early stages of regeneration of protoplasts of fungi and Streptomyces]. / Tsitologicheskoe izuchenie rannikh étapov regeneratsii protoplastov gribov i streptomitsetov.

Early stages of Penicillium chrysogenum 51 and Streptomyces lividans 66 protoplast regeneration on solid media were studied microscopically under conditions of microcompartments. It was shown that at the early regeneration stages there were both rapid reversion into the mycelial form and a retarded one. In P. chrysogenum retarded regeneration resulted in formation of hypha-like structures or protoplast breaking into fragments of various sizes. Some of the fragments restored the cell walls and mycelial organization whereas the others lysed. As a result of the breaking and compartmentalization of the viable areas one protoplasts formed several centers of P. chrysogenum colony reversion. Retarded regeneration of protoplasts in S. lividans 66 resulted in their growth and multiplication in the protoplast-like L-form. On media with penicillin, glycine and horse serum there were isolated colonies of S. lividans L-forms subject to passages or reversion depending on the medium composition.