title: Different polyketide folding modes converge to an identical molecular architecture.
abstract: Metabolic diversity is being studied intensively by evolutionary biologists, but so far there has been no comparison of biosynthetic pathways leading to a particular secondary metabolite in both prokaryotes and eukaryotes. We have detected the bioactive anthraquinone chrysophanol, which serves as a chemical defense in diverse eukaryotic organisms, in a bacterial Nocardia strain, thereby permitting the first comparative biosynthetic study. Two basic modes of folding a polyketide chain to fused-ring aromatic structures have so far been described: mode F (referring to fungi) and mode S (from Streptomyces). We have demonstrated that in eukaryotes (fungi, higher plants and insects), chrysophanol is formed via folding mode F. In actinomycetes, by contrast, the cyclization follows mode S. Thus, chrysophanol is the first polyketide synthase product that is built up by more than one polyketide folding mode.
authors.affiliation: Institute of Organic Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany. bringman@chemie.uni-wuerzburg.de
authors.forename: Gerhard
authors.initials: G
authors.lastname: Bringmann
authors.forename: Torsten F
authors.initials: TF
authors.lastname: Noll
authors.forename: Tobias A M
authors.initials: TA
authors.lastname: Gulder
authors.forename: Matthias
authors.initials: M
authors.lastname: Grüne
authors.forename: Michael
authors.initials: M
authors.lastname: Dreyer
authors.forename: Christopher
authors.initials: C
authors.lastname: Wilde
authors.forename: Florian
authors.initials: F
authors.lastname: Pankewitz
authors.forename: Monika
authors.initials: M
authors.lastname: Hilker
authors.forename: Gail D
authors.initials: GD
authors.lastname: Payne
authors.forename: Amanda L
authors.initials: AL
authors.lastname: Jones
authors.forename: Michael
authors.initials: M
authors.lastname: Goodfellow
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Fiedler
mesh_terms: D000818:Animals; D000880:Anthraquinones / Q000737:chemistry / Q000378:metabolism*; D003500:Cyclization; D005057:Eukaryotic Cells / Q000737:chemistry / Q000378:metabolism; D005658:Fungi / Q000737:chemistry / Q000378:metabolism*; D007313:Insecta; D007814:Larva; D009682:Magnetic Resonance Spectroscopy / Q000379:methods / Q000592:standards; D015394:Molecular Structure; D009615:Nocardia / Q000235:genetics / Q000378:metabolism; D048630:Polyketide Synthases / Q000737:chemistry; D012015:Reference Standards; D013302:Streptomyces / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000880:Anthraquinones; D048630:Polyketide Synthases; C027113:chrysophanic acid