title: Characterization of a fusarium 2-gene cluster involved in trichothecene C-8 modification.
abstract: The Fusarium trichothecenes T-2 toxin and deoxynivalenol (DON) are potent inhibitors of eukaryotic protein synthesis and are a significant agricultural problem. Three coregulated loci are required for T-2 toxin synthesis by Fusarium sporotrichioides. The core-trichothecene gene cluster consists of 12 genes (Tri3-Tri14) while the second locus consists of a single gene (Tri101). The third locus was recently partially described and encodes 1-2 biosynthetic enzymes and a putative regulatory gene. Here, we describe a detailed characterization of this locus. Located adjacent to Tri1 is Tri16, which is required for esterification of the C-8 hydroxyl. A putative regulatory gene, also adjacent to Tri1, is not required for T-2 toxin synthesis. The genomic sequence of Fusarium graminearum (a DON producer) contains a putative functional Tri1 and a nonfunctional Tri16. The presence of the Tri16 pseudogene is consistent with the chemical structure of DON, which has a C-8 keto group rather than the C-8 ester of T-2 toxin.
authors.affiliation: USDA/ARS, National Center for Agricultural Utilization Research, Peoria, Illinois 61604, USA. browndw@ncaur.usda.gov
authors.forename: Daren W
authors.initials: DW
authors.lastname: Brown
authors.forename: Robert H
authors.initials: RH
authors.lastname: Proctor
authors.forename: Rex B
authors.initials: RB
authors.lastname: Dyer
authors.forename: Ronald D
authors.initials: RD
authors.lastname: Plattner
mesh_terms: D000217:Acyltransferases / Q000235:genetics; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics; D004951:Esterification; D020224:Expressed Sequence Tags; D005670:Fusarium / Q000201:enzymology / Q000235:genetics*; D017353:Gene Deletion; D008969:Molecular Sequence Data; D012045:Regulatory Sequences, Nucleic Acid; D014255:Trichothecenes / Q000378:metabolism*
chemical_list: D014255:Trichothecenes; D003577:Cytochrome P-450 Enzyme System; D000217:Acyltransferases