ABSTRACT
ABSTRACT: Trichothecene-detoxifying enzyme, trichothecene-3-O-acetyltransferase (Tri101), and its reversible acetylation of DON suggested that Tri101 is a Fusarium self-defensive enzyme, and hence used to generate DON-resistant crops following Tri101-transformation. Bacterial isolates and their protein extracts showed deacetylation activity of 3-acetyldeoxynivalenol (3ADON), an intermediate in DON biosynthesis, similar to certain Fusarium species. Dot blot and Southern blot assays using Tri101 probe showed positive signals with 8 out of 16 tested bacterial isolates. Polymerase chain reaction (PCR) using normal and degenerate primers created from conserved Tri101 sequences showed amplified bands, none of them were Tri101 but some possessed transferase domain. The phylogenetic relationship indicated clustering of Fusarium Tri101 with somewhat closer relation to one of the bacterial isolates, Barpee. These results revealed a Tri101-like function from certain bacterial strains and a possible bacterial acetyltransferase targeting trichothecenes as its substrate.
