title: Isolation and Structure Elucidation of Fujikurins A-D: Products of the PKS19 Gene Cluster in Fusarium fujikuroi.
abstract: Fusarium fujikuroi is a member of the Gibberella fujikuroi species complex and well known for the production of gibberellins and mycotoxins including fusarins and fusaric acid. A recent genome sequencing study revealed that the fungus has the genetic potential to produce many more secondary metabolites than have been reported. This paper describes the structure elucidation of the products of the cryptic and silent PKS19 gene cluster that were recently identified (fujikurins A-D). We present the complete NMR data for the structure elucidation of the main compound fujikurin D, which shows tautomeric 1,3-diketo elements. The different tautomeric structures could be confirmed using quantum chemical calculations. Additionally, the structures of the minor compounds fujikurins A-C were elucidated by high-resolution mass spectrometric fragmentation experiments. It emerged that fujikurin A was identical to the bioactive compound CR377 of the taxonomically unclassified Fusarium strain CR377, while fujikurins B-D have not been reported from other fungi.
authors.affiliation: Institute of Food Chemistry, Westfälische Wilhelms-Universität Münster , Corrensstraße 45, 48149 Münster, Germany.
authors.forename: Katharina Walburga
authors.initials: KW
authors.lastname: von Bargen
authors.affiliation: Institute of Molecular Biology and Biotechnology of Fungi, Westfälische Wilhelms-Universität Münster , Schlossplatz 8, 48143 Münster, Germany.
authors.forename: Eva-Maria
authors.initials: EM
authors.lastname: Niehaus
authors.affiliation: Institute of Food Chemistry, Westfälische Wilhelms-Universität Münster , Corrensstraße 45, 48149 Münster, Germany.
authors.forename: Isabel
authors.initials: I
authors.lastname: Krug
authors.affiliation: Institute of Organic Chemistry, Westfälische Wilhelms-Universität Münster , Corrensstraße 40, 48149 Münster, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Bergander
authors.affiliation: Institute of Organic Chemistry, Westfälische Wilhelms-Universität Münster , Corrensstraße 40, 48149 Münster, Germany.
authors.forename: Ernst-Ulrich
authors.initials: EU
authors.lastname: Würthwein
authors.affiliation: Institute of Molecular Biology and Biotechnology of Fungi, Westfälische Wilhelms-Universität Münster , Schlossplatz 8, 48143 Münster, Germany.
authors.forename: Bettina
authors.initials: B
authors.lastname: Tudzynski
authors.affiliation: Institute of Food Chemistry, Westfälische Wilhelms-Universität Münster , Corrensstraße 45, 48149 Münster, Germany.
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Humpf
mesh_terms: D001483:Base Sequence; D005669:Fusaric Acid / Q000096:biosynthesis; D005670:Fusarium / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D005875:Gibberellins / Q000378:metabolism*; D015394:Molecular Structure; D005810:Multigene Family; D009183:Mycotoxins / Q000096:biosynthesis* / Q000378:metabolism; D011753:Pyrones / Q000737:chemistry; D014255:Trichothecenes / Q000737:chemistry
chemical_list: C416587:CR 377; D005875:Gibberellins; D009183:Mycotoxins; D011753:Pyrones; D014255:Trichothecenes; D005669:Fusaric Acid