title: Screening of putative oxygenase genes in the Fusarium graminearum genome sequence database for their role in trichothecene biosynthesis.
abstract: In the biosynthesis of type B trichothecenes, four oxygenation steps remain to have genes functionally assigned to them. On the basis of the complete genome sequence of Fusarium graminearum, expression patterns of all oxygenase genes were investigated in Fusarium asiaticum (F. graminearum lineage 6). As a result, we identified five cytochrome P450 monooxygenase (CYP) genes that are specifically expressed under trichothecene-producing conditions and are unique to the toxin-producing strains. The entire coding regions of four of these genes were identified in F. asiaticum. When expressed in Saccharomyces cerevisiae, none of the oxygenases were able to transform trichodiene-11-one to expected products. However, one of the oxygenases catalyzed the 2beta-hydroxylation rather than the expected 2alpha-hydroxylation. Targeted disruption of the five CYP genes did not alter the trichothecene profiles of F. asiaticum. The results are discussed in relation to the presence of as-yet-unidentified oxygenation genes that are necessary for the biosynthesis of trichothecenes.
authors.affiliation: Laboratory for Remediation Research, and Plant and Microbial Metabolic Engineering Unit-Laboratory, Plant Science Center (PSC1) and Discovery Research Institute, RIKEN, Wako, Saitama 351-0198, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tokai
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Koshino
authors.forename: Tsuneomi
authors.initials: T
authors.lastname: Kawasaki
authors.forename: Tomoko
authors.initials: T
authors.lastname: Igawa
authors.forename: Yoshikatsu
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Masayuki
authors.initials: M
authors.lastname: Sato
authors.forename: Makoto
authors.initials: M
authors.lastname: Fujimura
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Eizuka
authors.forename: Hidenori
authors.initials: H
authors.lastname: Watanabe
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kitahara
authors.forename: Kunihiro
authors.initials: K
authors.lastname: Ohta
authors.forename: Takehiko
authors.initials: T
authors.lastname: Shibata
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Kudo
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Inoue
authors.forename: Isamu
authors.initials: I
authors.lastname: Yamaguchi
authors.forename: Makoto
authors.initials: M
authors.lastname: Kimura
mesh_terms: D004271:DNA, Fungal / Q000032:analysis / Q000235:genetics; D030541:Databases, Genetic; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005670:Fusarium / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D016681:Genome, Fungal; D010105:Oxygenases / Q000235:genetics* / Q000378:metabolism; D014255:Trichothecenes / Q000096:biosynthesis* / Q000737:chemistry / Q000378:metabolism
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; D014255:Trichothecenes; D010105:Oxygenases