Submitted to: Meeting Abstract
Publication Type: Abstract only
Publication Acceptance Date: 11/4/2009
Publication Date: 11/4/2009
Citation: Schneiderman, D., Mccormick, S.P., Alexander, N.J., Johnston, A., Harris, L.J. 2009. Disruption of Genes Involved in Butenolide and Culmorin Synthesis in Fusarium graminearum [abstract]. Interpretive Summary:
Technical Abstract: Butenolide (4-acetamide-4-hydroxy-2-butenoic acid '-lactone) and culmorin (a tricyclic sesquiterpene diol) are two less-studied mycotoxins produced by several Fusarium species, including Fusarium graminearum. A putative butenolide biosynthetic eight-gene cluster in F. graminearum includes fg08080 which encodes a zinc-finger protein and may function as a regulatory gene for the cluster. Gene disruption of fg08080 resulted in loss of butenolide biosynthesis and the down-regulation of other genes within the cluster. Fusarium infection in wheat revealed no difference in virulence between the fg08080-disrupted and wild-type strains. fg08080 is required for butenolide biosynthesis in F. graminearum and may control butenolide biosynthesis through regulation of the gene cluster. A terpene synthase gene, fg10397, was observed to be induced under trichothecene-inducing conditions and during plant infection (based on EST library representation, Northern and microarray analysis). Transformed yeast cultures expressing FG10397 produced longiborneol, a terpene with the same tricyclic structure as culmorin, which was not produced by the progenitor yeast strain. The fg10397 gene was disrupted in F. graminearum strain 9F1, a wild-type strain that produces a significant amount of culmorin in vitro. No culmorin was produced by 9F1 strains with a disrupted fg10397 while wild-type and fg10397 add-back strains produced culmorin in liquid cultures. fg10397 encodes a longiborneol synthase that is required for culmorin synthesis.