Trichothecene 3-O-acetyltransferase protects both the producing organism and transformed yeast from related mycotoxins. Cloning and characterization of Tri101

• Published in: The Journal of biological chemistry Vol. 273; no. 3; pp. 1654 - 1661
• Main Authors: Kimura, M, Kaneko, I, Komiyama, M, Takatsuki, A, Koshino, H, Yoneyama, K, Yamaguchi, I
• Format: Journal Article
• Language: English
• Published: United States 16.01.1998
• Subjects: ACETILACION; ACETYLATION; Acetyltransferases - chemistry; Acetyltransferases - genetics; Acetyltransferases - metabolism; ACILTRANSFERASA; ACTIVIDAD ENZIMATICA; ACTIVITE ENZYMATIQUE; ACYLTRANSFERASE; ACYLTRANSFERASES; ADN; Amino Acid Sequence; AMINO ACID SEQUENCES; Animals; Base Sequence; Cell Line; CHEMICAL COMPOSITION; CLONACION; CLONAGE; CLONING; Cloning, Molecular; COMPLEMENTARY DNA; COMPOSICION QUIMICA; COMPOSITION CHIMIQUE; Cricetinae; CYTOTOXICITY; DNA; ENZYMIC ACTIVITY; EXPRESION GENICA; EXPRESSION DES GENES; GENBANK/AB000874; GENE; GENE EXPRESSION; GENE TRANSFER; GENES; GENETIC TRANSFORMATION; GENETICA; GENETICS; GENETIQUE; GIBBERELLA ZEAE; Models, Chemical; MOLECULAR MAPPING; MOLECULAR SEQUENCE DATA; Mycotoxins - pharmacology; NUCLEOTIDE SEQUENCE; OPEN READING FRAMES; Plasmids - drug effects; PROTECTION; Rabbits; RESTRICTION MAPPING; SCHIZOSACCHAROMYCES POMBE; SECUENCIA NUCLEOTIDICA; SEQUENCE NUCLEOTIDIQUE; STRUCTURAL GENES; T-2 Toxin - pharmacology; TOXICIDAD; TOXICITE; TOXICITY; TRANSFERENCIA DE GENES; TRANSFERT DE GENE; TRANSFORMACION GENETICA; TRANSFORMATION GENETIQUE; TRI101 GENE; TRICHOTHECENE; TRICHOTHECENES; Trichothecenes - biosynthesis
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.273.3.1654

Trichothecene mycotoxins such as deoxynivalenol, 4,15-diacetoxyscirpenol, and T-2 toxin, are potent protein synthesis inhibitors for eukaryotic organisms. The 3-O-acetyl derivatives of these toxins were shown to reduce their in vitro activity significantly as assessed by assays using a rabbit reticulocyte translation system. The results suggested that the introduction of an O-acetyl group at the C-3 position in the biosynthetic pathway works as a resistance mechanism for Fusarium species that produce t-type trichothecenes (trichothecenes synthesized via the precursor trichotriol). A gene responsible for the 3-O-acetylation reaction, Tri101, has been successfully cloned from a Fusarium graminearum cDNA library that was designed to be expressed in Schizosaccharomyces pombe. Fission yeast transformants were selected for their ability to grow in the presence of T-2 toxin, and this strategy allowed isolation of 25 resistant clones, all of which contained a cDNA for Tri101. This is the first drug-inactivating O-acetyltransferase gene derived from antibiotic-producing organisms. The open reading frame of Tri101 codes for a polypeptide of 451 amino acid residues, which shows no similarity to any other proteins reported so far. TRI101 from recombinant Escherichia coli catalyzes O-acetylation of the trichothecene ring specifically at the C-3 position in an acetyl-CoA-dependent manner. By using the Tri101 cDNA as a probe, two least overlapping cosmid clones that cover a region of 70 kilobase pairs have been isolated from the genome of F. graminearum. Other trichothecene biosynthetic genes, Tri4, Tri5, and Tri6, were not clustered in the region covered by these cosmid clones. These new cosmid clones are considered to be located in other parts of the large biosynthetic gene cluster and might be useful for the study of trichothecene biosynthesis.