title: pks63787, a Polyketide Synthase Gene Responsible for the Biosynthesis of Benzenoids in the Medicinal Mushroom Antrodia cinnamomea.
abstract: Antrodia cinnamomea, a unique resupinate basidiomycete endemic to Taiwan, has potent medicinal activities. The reddish basidiocarps and mycelia generally exhibit abundant metabolites and higher biological activity. To investigate the pigments of A. cinnamomea, polyketide synthase (PKS) genes were characterized based on its partially deciphered genome and the construction of a fosmid library. Furthermore, a gene disruption platform was established via protoplast transformation and homologous recombination. Of four putative polyketide synthase genes, pks63787 was selected and disrupted in the monokaryotic wild-type (wt) strain f101. Transformant Δpks63787 was deficient in the synthesis of several aromatic metabolites, including five benzenoids and two benzoquinone derivatives. Based on these results, a biosynthetic pathway for benzenoid derivatives was proposed. The pks63787 deletion mutant not only displayed a reduced red phenotype compared to the wt strain but also displayed less 1,1-biphenyl-2-picrylhydrazyl free radical scavenging activity. This finding suggests that PKS63787 is responsible for the biosynthesis of pigments and metabolites related to the antioxidant activity of A. cinnamomea. The present study focuses on the functional characterization of the PKS gene, the fluctuations of its profile of secondary metabolites, and interpretation of the biosynthesis of benzenoids.
authors.forename: Po-Wei
authors.initials: PW
authors.lastname: Yu
authors.affiliation: College of Pharmacy, Taipei Medical University , Taipei, Taiwan 110.
authors.forename: Ya-Chih
authors.initials: YC
authors.lastname: Chang
authors.forename: Ruey-Fen
authors.initials: RF
authors.lastname: Liou
authors.forename: Tzong-Huei
authors.initials: TH
authors.lastname: Lee
authors.forename: Shean-Shong
authors.initials: SS
authors.lastname: Tzean
mesh_terms: D000363:Agaricales / Q000201:enzymology*; D055491:Antrodia / Q000737:chemistry / Q000201:enzymology / Q000235:genetics; D016227:Benzoquinones / Q000032:analysis / Q000737:chemistry; D001713:Biphenyl Compounds / Q000494:pharmacology; D004247:DNA / Q000032:analysis; D016166:Free Radical Scavengers / Q000494:pharmacology; D048690:Fruiting Bodies, Fungal; D015394:Molecular Structure; D025282:Mycelium / Q000378:metabolism; D019906:Nuclear Magnetic Resonance, Biomolecular; D010851:Picrates / Q000494:pharmacology; D048630:Polyketide Synthases / Q000235:genetics* / Q000378:metabolism*; D012313:RNA / Q000032:analysis; D013624:Taiwan
chemical_list: D016227:Benzoquinones; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D010851:Picrates; C004532:quinone; D012313:RNA; D048630:Polyketide Synthases; D004247:DNA; C004931:1,1-diphenyl-2-picrylhydrazyl