Title: Myrothecium Roridum Tri4 Controls Three Oxygenation Steps in Macrocylic Trichothecene Biosynthesis. Authors
Submitted to: Phytochemical Society of North America Meeting and Newsletter
Publication Type: Abstract Only
Publication Acceptance Date: June 21, 2006
Publication Date: July 8, 2006
Citation: Mc Cormick, S.P., Alexander, N.J. 2006. Myrothecium roridum tri4 controls three oxygenation steps in macrocylic trichothecene biosynthesis [abstract]. Phytochemical Society of North America Meeting and Newsletter. Abstract 11. p. 25. Technical Abstract: Macrocyclic trichothecenes are toxic sesquiterpenoids that are produced by certain fungi and plants. The unique structural features of macrocyclic trichothecenes make them 10-fold more toxic than Fusarium trichothecenes. Myrothecium roridum has been previously reported to contain at least three trichothecene biosynthetic genes that are comparable to genes to in Fusarium sporotrichioides, Tri4, Tri5 and Tri6. MRTRI4 gene has 63% identity with FSTri4. We have recently shown that FsTri4 controls the first four oxygenations in Fusarium trichothecene biosynthesis. MrTri4 complemented a Tri4 mutant of F. sporotrichioides but did not result in a wild-type trichothecene profile, producing only minimal amounts of T-2 toxin. In this study we expressed MrTri4 in Fusarium verticillioides, a species that does not produce trichothecenes and found that exogenous trichodiene was converted to isotrichodiol. The results indicate that MrTri4 controls the first three oxygenation steps in Myrothecium macrocyclic trichothecene biosynthesis.