title: Absolute configuration of ceriporic acids, the iron redox-silencing metabolites produced by a selective lignin-degrading fungus, Ceriporiopsis subvermispora.
abstract: Ceriporic acids are a class of alk(en)ylitaconic acids produced by a selective lignin-degrading fungus, Ceriporiopsis subvermispora. The unique function of alkylitaconic acid is the redox silencing of the Fenton reaction system by inhibiting reduction of Fe(3+). Ceriporic acids have an asymmetric centre at carbon-3, but absolute configuration has not been determined. We have isolated a series of ceriporic acids from the cultures of C. subvermispora, and measured their NMR spectra using a chiral shift reagent. In comparison with NMR spectra of (R)-(-)- and (S)-(+)-methylsuccinic acid and those of natural and chemically synthesized racemic mixtures of ceriporic acids, we have determined the absolute configuration of ceriporic acids as (R)-3-tetradecylitaconic acid (ceriporic acid A), (R)-3-hexadecylitaconic acid (ceriporic acid B) and (R,Z)-2-(hexadec-7-enyl)-3-itaconic acid (ceriporic acid C). We herein discuss their stereoselective biosynthetic pathway and the structural diversity of fungal secondary metabolites.
authors.affiliation: Laboratory of Biomass Conversion, Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji, Kyoto, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nishimura
authors.forename: Kyoko
authors.initials: K
authors.lastname: Murayama
authors.forename: Takahito
authors.initials: T
authors.lastname: Watanabe
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Honda
authors.forename: Takashi
authors.initials: T
authors.lastname: Watanabe
mesh_terms: D000475:Alkenes / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D055453:Coriolaceae / Q000378:metabolism*; D003998:Dicarboxylic Acids / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D007501:Iron / Q000737:chemistry*; D008031:Lignin / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D010084:Oxidation-Reduction; D013237:Stereoisomerism
chemical_list: D000475:Alkenes; D003998:Dicarboxylic Acids; C506480:ceriporic acid B; C488844:ceriporic acid C; C534201:ceriporic acid D; D008031:Lignin; D007501:Iron