[Preparation of an active strain of Bacillus licheniformis--producer of thermostable alpha-amylase].

A highly potent strain of Bacillus licheniformis 103 that synthesized thermostable alpha-amylase with temperature and pH optima of 90-95 degrees C and 6.0-8.5, respectively, was obtained by mutagenesis and selection.

[Isolation of peptide antibiotic virginiamycin components and selection of their producer Streptomyces virginiae].

A method for chromatographic separation and quantitative determination of individual components of the antibiotic virginiamycin, produced by microbiological synthesis (Streptomyces virginiae strain 147), is described. The components, M1-2 and S1-5, were isolated from fermentation broth and identified by HPTLC and HPLC (the results obtained using the two methods correlate well with each other). Conditions of culturing of the producer and compositions of nutritive media were optimized.

[Molecular genetic study of the strain Streptomyces virginiae-- the producer of virginiamycin].

The level and the character of the Streptomyces virginiae virginiamycin-producing strain's resistance to self-produced antibiotic and a number of antibiotics from different groups were determined. S. virginiae was shown to display constitutive and inducible resistance to self-produced antibiotic.

[Isolation and characteristics of a plasmid from the thermotolerant strain of Bacillus licheniformis].

A 8.3 kb cryptic plasmid was isolated from the thermotolerant strain of Bacillus licheniformis 28KA and designated pLT83. The replicative (rep) region was localized on the plasmid map.

[Fusion of Bacillus subtilis and Bacillus licheniformis protoplasts. The mapping of the mutations leading to the supersynthesis of riboflavin in interspecies hybrids].

As a result of fusion of the protoplasts of B. subtilis and B. licheniformis the majority of the prototrophic hybrids, as well as the auxotrophs with the Thi-Hom-phenotype or the Thi-phenotype acquired capacity for over-production of riboflavin lacking in the initial parent strains.