Biosynthesis of photodynamically active rubellins and structure elucidation of new anthraquinone derivatives produced by Ramularia collo-cygni.
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.
Miethbauer
Sebastian
S
Friedrich-Schiller-Universität Jena, Institut für Pharmazie, Neugasse 23, D-07743 Jena, Germany.
Haase
Susann
S
Schmidtke
Kai-Uwe
KU
Günther
Wolfgang
W
Heiser
Ingrid
I
Liebermann
Bernd
B
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
D000880:Anthraquinones; D002247:Carbon Isotopes; D018942:Macrolides; C514655:rubellin A