title: [Nature of the brown pigment and the composition of the phenol oxidases of Streptomyces galbus].
abstract: The culture of Streptomyces galbus ISP-5089 has a yellow-green colour caused by the accumulation of actinomycin X when it is grown in synthetic media at 28 degrees C; the colour turns dark-brown at 42 degrees C due to the synthesis of melanoid pigments. The population composition does not undergo any noticeable changes in that case, an no specific melanin-synthesizing mutants appear as a result of autoselection . The biosynthesis of actinomycin X (at 28 degrees C) and melanoid pigments (at 42 degrees C) is regulated by temperature. At 42 degrees C, L-DOPA oxidase is synthesized and laccase is activated; these two enzymes are involved in the synthesis of melanoid pigments. The organism does not has tyrosinase. The synthesis of melanoid pigments, when the mesophilic culture of S. galbus ISP-5089 is grown in the regime of superoptimal temperatures (42 to 47 degrees C), may be considered as a protective ecological reaction of the organism to unfavourable conditions of the environment.
mesh_terms: D004156:Catechol Oxidase / Q000378:metabolism*; D003470:Culture Media / Q000378:metabolism; D003609:Dactinomycin / Q000096:biosynthesis / Q000031:analogs & derivatives; D004578:Electron Spin Resonance Spectroscopy; D042845:Laccase; D014442:Monophenol Monooxygenase / Q000378:metabolism*; D010088:Oxidoreductases / Q000378:metabolism; D010860:Pigments, Biological / Q000032:analysis / Q000096:biosynthesis*; D013053:Spectrophotometry; D013302:Streptomyces / Q000145:classification / Q000378:metabolism*; D013696:Temperature; D014443:Tyrosine / Q000378:metabolism
chemical_list: D003470:Culture Media; D010860:Pigments, Biological; D003609:Dactinomycin; D014443:Tyrosine; C041783:actinomycin X; D010088:Oxidoreductases; D004156:Catechol Oxidase; D042845:Laccase; D014442:Monophenol Monooxygenase
vernacular_title: O prirode burogo pigmenta i sostave fenoloksidaz Streptomyces galbus.