title: [Selection of mutant branched-chain amino acid producers in the methylotrophic yeasts Hansenula polymorpha].
abstract: The object of the work was to test several methods for selection of the methylotrophic yeast Hansenula polymorpha mutants accumulating amino acids with a branched chain (valine, leucine, isoleucine). Selection of strains resistant to norvaline, an analogue of valine and leucine, was found to be the most effective method. The mutants were grown in a medium with methanol and accumulated mainly valine and, in lesser quantities, leucine, isoleucine, aspartate, asparagine and a cysteine derivative. The mutants accumulated up to 110 mg of amino acids per 1 L of the cultural broth, while the wild type strain accumulated only 5 mg/L.
mesh_terms: D000597:Amino Acids, Branched-Chain / Q000096:biosynthesis*; D001203:Ascomycota / Q000378:metabolism*; D003470:Culture Media / Q000378:metabolism; D004352:Drug Resistance, Microbial; D009154:Mutation; D010843:Pichia / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D012641:Selection, Genetic; D014466:Ultraviolet Rays; D014633:Valine / Q000494:pharmacology / Q000031:analogs & derivatives
chemical_list: D000597:Amino Acids, Branched-Chain; D003470:Culture Media; C005313:norvaline; D014633:Valine
vernacular_title: Selektsiia mutantov-produtsentov aminokislot s razvetvelennoĭ tsep'iu u metilotrofnykh drozhzheĭ Hansenula polymorpha.