A NOVEL TYPE OF PEROXIDASE GENE FROM THE WHITE-ROT FUNGUS TRAMETES-VERSICOLOR

The wood-decaying fungus Trametes versicolor secretes a large number of peroxidase isozymes, presumed to partake in the degradation of lignin. From enzymic studies, two types of peroxidases have been distinguished: lignin peroxidases and manganese peroxidases. We here report the finding of a T. versicolor peroxidase gene, PG V, which displays several features not observed in previously studied peroxidase genes from white-rot fungi, such as a high number of introns (12). Eight of the 12 introns have positions equivalent to introns of peroxidase genes from another white-rot fungus, Phanerochaete chrysosporium. The gene structure of PG V appears to be primarily related to known lignin peroxidase genes, white the encoded mature 339-residue protein has several characteristics in common with manganese peroxidases. Analyses further indicate that PG V encodes a Ser instead of an Asn at a position regarded as invariant within the enzyme superfamily, with the side chain involved in hydrogen bonding with the distal His.