title: A new enzyme involved in the control of the stereochemistry in the decalin formation during equisetin biosynthesis.
abstract: Tetramic acid containing a decalin ring such as equisetin and phomasetin is one of the characteristic scaffolds found in fungal bioactive secondary metabolites. Polyketide (PKS)-nonribosomal peptide synthetase (NRPS) hybrid enzyme is responsible for the synthesis of the polyketide scaffold conjugated with an amino acid. PKS-NRPS hybrid complex programs to create structural diversity in the polyketide backbone have begun to be investigated, yet mechanism of control of the stereochemistry in a decalin formation via a Diels-Alder cycloaddition remains uncertain. Here, we demonstrate that fsa2, which showed no homology to genes encoding proteins of known function, in the fsa cluster responsible for equisetin and fusarisetin A biosynthesis in Fusarium sp. FN080326, is involved in the control of stereochemistry in decalin formation via a Diels-Alder reaction in the equisetin biosynthetic pathway.
authors.affiliation: Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Kato
authors.affiliation: Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Nogawa
authors.affiliation: Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan; RIKEN-KRIBB Joint Research Unit, Global Research Cluster, RIKEN, Wako, Saitama 351-0198, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hirota
authors.affiliation: Chemical Biology Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 30 Yeongudanji-ro, Ochang, Cheongwon, Chungbuk 363-883, Republic of Korea.
authors.forename: Jae-Hyuk
authors.initials: JH
authors.lastname: Jang
authors.affiliation: Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan; RIKEN-KRIBB Joint Research Unit, Global Research Cluster, RIKEN, Wako, Saitama 351-0198, Japan.
authors.forename: Shunji
authors.initials: S
authors.lastname: Takahashi
authors.affiliation: Chemical Biology Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 30 Yeongudanji-ro, Ochang, Cheongwon, Chungbuk 363-883, Republic of Korea.
authors.forename: Jong Seog
authors.initials: JS
authors.lastname: Ahn
authors.affiliation: Chemical Biology Research Group, RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan. Electronic address: hisyo@riken.jp.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Osada
mesh_terms: D005670:Fusarium / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D005800:Genes, Fungal; D005810:Multigene Family; D009281:Naphthalenes / Q000378:metabolism*; D048630:Polyketide Synthases / Q000378:metabolism*; D011760:Pyrrolidinones / Q000378:metabolism*; D013237:Stereoisomerism; D013764:Tetrahydronaphthalenes / Q000378:metabolism*
chemical_list: D009281:Naphthalenes; D011760:Pyrrolidinones; D013764:Tetrahydronaphthalenes; C024509:equisetin; D048630:Polyketide Synthases; C007229:decalin
keywords: Biosynthesis; Decalin; Diels-Alder cycloaddition; Fusarium PKS-NRPS hybrid; Secondary metabolite