Kenneth A. Devor

Trichodiene is a precursor to trichothecenes

Trichodiene was rigorously proven to be a biosynthetic precursor to the major trichothecenes in Fusarium culmorum: 3-acetyldeoxynivalenol and sambucinol; bazzanene, an unnatural diastereoisomer of trichodiene (with a β-methyl at C-15), was not incorporated into trichothecenes.

Biosynthesis of trichothecenes: oxygenation steps post-trichodiene

Two dioxygenated derivatives of trichodiene 1 have been isolated from Fusarium culmorum cultures treated with the inhibitor ancymidol and characterized as 9,10-trichoene-12,13-diol 2 and 12, 13-epoxy-9, 10-trichoene-2-ol 3; radiolabelling experiments demonstrate that 2 is a dead-end metabolite whereas 3 is incorporated into both 3-acetyldeoxynivalenol 4 and sambucinol 7.

Biosynthesis of the trichothecene 3-acetyldeoxynivalenol: cell-free hydroxylations of isotrichodermin.

3-Acetyldeoxynivalenol is the major trichothecene produced by the fungus Fusarium culmorum. Studies in vivo with F. culmorum have established the following biosynthetic precursors of 3-acetyldeoxynivalenol: isotrichool → isotrichodiol → isotrichodermin → 15-deacetylcalonectrin, 7α-hydroxyisotrichodermin, 8α-hydroxyisotrichodermin → calonectrin → deoxynivalenol. In this paper, we describe in vitro investigations of one of these metabolic steps. The cell-free system of F. culmorum that converts isotrichodermin into 15-deacetylcalonectrin, 7α-hydroxyisotrichodermin, and 8α-hydroxyisotrichodermin is described here. This preparation requires NADPH but not NADH for activity and is not inhibited by carbon monoxide, cyanide, or known oxygenase inhibitors, such as SKF-525-A or ancymidol.Key words: trichothecene, Fusarium culmorum, cell-free system, isotrichodermin, 15-deacetylcalonectrin.

Structures of new metabolites from Fusarium species : an apotrichothecene and oxygenated trichodienes

Abstract Three new natural products were isolated from Fusarium spp , one apotrichothecene and two oxygenated derivatives of trichodiene. The apotrichothecene was a precursor to apotrichodiol and sambucinol.

Mechanism of 3-acetyldeoxynivalenol biosynthesis

The distribution of label of the trichothecene, 3-acetyldeoxynivalenol (3-ADN) derived from mevalonate and three of the major steps in its biosynthesis (the folding of farnesyl pyrophosphate, the methyl shifts, and the stereochemistry of oxygenation) were rigorously proven.