Characterization of the gene encoding manganese peroxidase isozyme 3 from Phanerochaete chrysosporium.

The gene encoding manganese peroxidase isozyme 3 (MnP3) from the white-rot basidiomycete Phanerochaete chrysosporium was cloned and sequenced. The mnp3 gene encodes a mature protein of 357 amino acids with a 25 amino-acid signal peptide. The amino acids involved in peroxidase function, as well as those forming the MnII binding site and those involved in disulfide bond formation, are conserved in the MnP3 sequence. The mnp3 gene has six introns, indicating that the sequenced P. chrysosporium mnp genes can be divided into three subfamilies on the basis of intron-exon structure. The mnp3 gene promoter contains putative metal response elements and heat shock elements which may be involved in the regulation of mnp gene transcription by Mn, the substrate for the enzyme, and by heat shock.