title: [Effect of rib83 mutation on riboflavin biosynthesis and iron assimilation in Pichia guilliermondii].
abstract: The monogenic rib83 mutation blocked riboflavin oversynthesis in the yeast Pichia guilliermondii and lowered iron acquisition by cells, their ferric reductase activity, and the growth rate in iron-deficient media. Mutants with the combined mutations of rib83 with rib80 and rib81 (the last two mutations impair the negative control of riboflavin synthesis and thus cause its oversynthesis) were unable to depress the enzymes of flavinogenesis (GTP cyclohydrolase and riboflavin synthase) and to overproduce riboflavin in both iron-deficient and iron-sufficient media. This suggests that the rib83 mutation is epistatic with respect to the rib80 and rib81 mutations. The RIB83 gene may positively control both riboflavin synthesis and iron acquisition in the yeast P. guilliermondii.
authors.affiliation: Institute of Cell Biology, National Academy of Sciences of Ukraine, Lviv, Ukraine.
authors.forename: N N
authors.initials: NN
authors.lastname: Stenchuk
authors.forename: V I
authors.initials: VI
authors.lastname: Kutsiaba
authors.forename: B V
authors.initials: BV
authors.lastname: Kshanovskaia
authors.forename: D V
authors.initials: DV
authors.lastname: Fedorovich
mesh_terms: D003470:Culture Media; D006136:GTP Cyclohydrolase / Q000378:metabolism; D007501:Iron / Q000378:metabolism*; D009154:Mutation; D010843:Pichia / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D012256:Riboflavin / Q000096:biosynthesis*; D012258:Riboflavin Synthase / Q000378:metabolism
chemical_list: D003470:Culture Media; D007501:Iron; D012258:Riboflavin Synthase; D006136:GTP Cyclohydrolase; D012256:Riboflavin
vernacular_title: Vliianie mutatsii rib83 na biosintez riboflavina i assimiliatsiiu zheleza u drozhzheĭ Pichia guilliermondii.