title: Menaquinone (vitamin K2)-6 production by mutants of Flavobacterium meningosepticum.
abstract: Flavobacterium meningosepticum IFO 12535, a menaquinone (MK) producer, was mutagenized to improve productivity. A mutant, which was resistant to 1-hydroxy-2-naphthoate (HNA), was found to produce MK more abundantly: 34 mg/liter of culture broth and 5.5 mg/g of dry cells. The mutant was less sensitive to inhibition by HNA on MK biosynthesis than the wild-type strain. MK was isolated from cells of the mutant and identified as MK-6 based on its physicochemical characteristics. Mutants, which were given each KCN resistance, aromatic amino acid auxotrophy and no carotenoid productivity, did not show further increase of productivity.
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D002338:Carotenoids / Q000096:biosynthesis; D004352:Drug Resistance, Microbial; D005417:Flavobacterium / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D009284:Naphthols / Q000494:pharmacology; D011190:Potassium Cyanide / Q000494:pharmacology; D014812:Vitamin K / Q000096:biosynthesis*
chemical_list: D000596:Amino Acids; D009284:Naphthols; D014812:Vitamin K; D002338:Carotenoids; D011190:Potassium Cyanide; C050175:1-hydroxy-2-naphthoic acid