The trichothecene biosynthesis gene cluster of Fusarium graminearum F15 contains a limited number of essential pathway genes and expressed non-essential genes.
We report for the first time the complete structure and sequence of the trichothecene biosynthesis gene cluster (i.e. Tri5-cluster) from Fusarium graminearum F15, a strain that produces 3-acetyldeoxynivalenol (3-ADON). A putative tyrosinase and polysaccharide deacetylase gene flank the Tri5-cluster: the number of pathway genes between them is less than half the total number of steps necessary for 3-ADON biosynthesis. In comparison with partial Tri5-cluster sequences of strains with 15-acetyldeoxynivalenol and 4-acetylnivalenol chemotypes, the Tri5-cluster from strain F15 contains three genes that are apparently unnecessary for the biosynthesis of 3-ADON (i.e. Tri8 and Tri3, which are expressed, and pseudo-Tri13, which is not expressed). In addition, the Tri7 gene was missing from the cluster. Recombinant TRI3 protein showed limited trichothecene C-15 acetylase activity. In contrast, recombinant TRI8 protein displayed no C-3 deacetylase activity, suggesting that the loss or alteration of function contribute directly to the chemotype difference.
Kimura
Makoto
M
Laboratory for Remediation Research, Plant Science Center, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan. mikimura@postman.riken.go.jp
Tokai
Takeshi
T
O'Donnell
Kerry
K
Ward
Todd J
TJ
Fujimura
Makoto
M
Hamamoto
Hiroshi
H
Shibata
Takehiko
T
Yamaguchi
Isamu
I
D005670:Fusarium / Q000235:genetics*; D020043:Genes, Essential; D005800:Genes, Fungal; D005822:Genetic Vectors; D008969:Molecular Sequence Data; D005810:Multigene Family; D011994:Recombinant Proteins / Q000235:genetics; D014255:Trichothecenes / Q000235:genetics*
D011994:Recombinant Proteins; D014255:Trichothecenes