title: Elucidation of Pyranonigrin Biosynthetic Pathway Reveals a Mode of Tetramic Acid, Fused γ-Pyrone, and exo-Methylene Formation.
abstract: Successful activation of the pyranonigrin biosynthetic gene cluster and gene knockout in Aspergillus niger plus in vivo and in vitro assays led to isolation of six new products, including a spiro cyclobutane-containing dimeric compound, which served as the basis for the proposed comprehensive pyranonigrin biosynthetic pathway. Two redox enzymes are key to forming the characteristic fused γ-pyrone core, and a protease homologue performs the exo-methylene formation.
authors.affiliation: Department of Pharmaceutical Sciences, University of Shizuoka , Shizuoka 422-8526, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Department of Pharmaceutical Sciences, University of Shizuoka , Shizuoka 422-8526, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Tsunematsu
authors.affiliation: Department of Pharmaceutical Sciences, University of Shizuoka , Shizuoka 422-8526, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Noguchi
authors.affiliation: School of Biosciences, The University of Nottingham Malaysia Campus , Semenyih, Selangor Darul Ehsan 43500, Malaysia.
authors.forename: Kinya
authors.initials: K
authors.lastname: Hotta
authors.affiliation: Department of Pharmaceutical Sciences, University of Shizuoka , Shizuoka 422-8526, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Watanabe
mesh_terms: D000475:Alkenes / Q000737:chemistry*; D001234:Aspergillus niger / Q000737:chemistry / Q000235:genetics*; D053898:Biosynthetic Pathways / Q000235:genetics; D008697:Methane / Q000031:analogs & derivatives; D015394:Molecular Structure; D005810:Multigene Family; D011753:Pyrones / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D011758:Pyrroles / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D011760:Pyrrolidinones / Q000737:chemistry*
chemical_list: D000475:Alkenes; D011753:Pyrones; D011758:Pyrroles; D011760:Pyrrolidinones; C522144:pyranonigrin A; C030011:carbene; C009435:tetramic acid; D008697:Methane