[A new selection method for obtaining mutants of Streptomyces glaucoachromogenes producing lambdamycin using the thermophilic phage-host system Tal/Thermoactinomyces vulgaris].

In order to obtain high-producing mutants of the lambdamycin producer Streptomyces glaucoachromogenes IMET 31 118, a new selection technique using the thermophilic phage-host system Tal/Thermoactinomyces vulgaris, was developed. Lambdamycin is a yellow-green pigment antibiotic of the chromoglycoside type with antimicrobial, antiviral, cancerostatic, and ergotropic activity in vitro and in vivo. The physicochemical properties of lambdamycin resemble those of chartreusin. By means of the selection technique developed the determination of the concentration-dependent influence of lambdamycin on bacterial growth inhibition and Tal-phage development in the agar diffusion sphere of mutagen-treated colonies is possible without time and material-consuming pre-tests. A positive correlation exists between the biosynthetic capacity of mutants on solid media and in fermentation liquors. Using this new selection technique, the titres of lambdamycin in fermentation liquors of mutants could be increased by 10 to 20 fold in comparison to the wild type strain.