Dataset for: Trametes versicolor Glutathione Transferase Xi 3, a dual Cys-GST with catalytic specificities of both Xi and Omega classes

Glutathione transferases (GSTs) from the Xi and Omega classes have a catalytic cysteine residue which gives them reductase activities. Until now, they have been assigned distinct substrates. While Xi GSTs specifically reduce glutathionyl-(hydro)quinones, Omega GSTs are specialized in the reduction of glutathionyl-acetophenones. Here we present the study of TvGSTX1 and TvGSTX3 isoforms from the wood-degrading fungus Trametes versicolor. TvGSTX1 reduces GS-menadione as expected while TvGSTX3 reduces both Xi and Omega substrates. A structural analysis indicates a broader active site for TvGSTX3 due to specific differences in the nature of the residues situated in the C-terminal helix α9. This feature could explain the catalytic duality of TvGSTX3. Based on phylogenetic analysis we propose that this duality might exist in other fungi.