Biosynthesis of 3-Acetyldeoxynivalenol and Sambucinol

• Published in: The Journal of biological chemistry 1999-04, Vol.274 (18), p.12269-12277
• Main Authors: Zamir, Lolita O., Nikolakakis, Anastasia, Huang, Liren, St-Pierre, Patrick, Sauriol, Françoise, Sparace, Salvatore, Mamer, Orval
• Format: Article
• Language: English
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.274.18.12269

The first two oxygenation steps post-trichodiene in the biosyntheses of the trichothecenes 3-acetyldeoxynivalenol and sambucinol were investigated. The plausible intermediates 2-hydroxytrichodiene (2α- and 2β-) and 12,13-epoxytrichodiene and the dioxygenated compounds 12,13-epoxy-9,10-trichoene-2-ol (2α- and 2β-) were prepared specifically labeled with stable isotopes. They were then fed separately and/or together to Fusarium culmorum cultures, and the derived trichothecenes were isolated, purified, and analyzed. The stable isotopes enable easy localization of the labels in the products by 2 H NMR, 13 C NMR, and mass spectrometry. We found that 2α-hydroxytrichodiene is the first oxygenated step in the biosynthesis of both 3-acetyldeoxynivalenol and sambucinol. The stereoisomer 2β-hydroxytrichodiene and 12,13-epoxytrichodiene are not biosynthetic intermediates and have not been isolated as metabolites. We also demonstrated that the dioxygenated 12,13-epoxy-9,10-trichoene-2α-ol is a biosynthetic precursor to trichothecenes as had been suggested in a preliminary work. Its stereoisomer was not found in the pathway. A further confirmation of our results was the isolation of both oxygenated trichodiene derivatives 2α-hydroxytrichodiene and 12,13-epoxy-9,10-trichoene-2α-ol as natural metabolites in F. culmorum cultures.