title: Biosynthesis of photodynamically active rubellins and structure elucidation of new anthraquinone derivatives produced by Ramularia collo-cygni.
abstract: Here we present the first isolation of the anthrachinone derivative rubellin A out of mycelium and culture filtrate of Ramularia collo-cygni. Furthermore, two compounds, rubellin E and 14-dehydro rubellin D were isolated and their structures elucidated. In comparison to the other rubellins, rubellin A shows increased photodynamic oxygen activation. By incorporating both [1-(13)C]-acetate and [2-(13)C]-acetate into the rubellins, we showed that such anthraquinone derivatives were biosynthesised via the polyketide pathway. The labelling pattern after being fed [U-(13)C(6)]-glucose proved the existence of fungal folding mode of the poly-beta-keto chain. The ability to produce rubellins is not limited to R. collo-cygni in the anamorph genus Ramularia.
authors.affiliation: Friedrich-Schiller-Universität Jena, Institut für Pharmazie, Neugasse 23, D-07743 Jena, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Miethbauer
authors.forename: Susann
authors.initials: S
authors.lastname: Haase
authors.forename: Kai-Uwe
authors.initials: KU
authors.lastname: Schmidtke
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Günther
authors.forename: Ingrid
authors.initials: I
authors.lastname: Heiser
authors.forename: Bernd
authors.initials: B
authors.lastname: Liebermann
mesh_terms: D000880:Anthraquinones / Q000737:chemistry* / Q000378:metabolism*; D001203:Ascomycota / Q000737:chemistry* / Q000378:metabolism*; D002247:Carbon Isotopes; D018942:Macrolides / Q000737:chemistry / Q000378:metabolism; D015394:Molecular Structure; D013045:Species Specificity
chemical_list: D000880:Anthraquinones; D002247:Carbon Isotopes; D018942:Macrolides; C514655:rubellin A