Expression of the Lignin Peroxidase H2 Gene fromPhanerochaete chrysosporiuminEscherichia coli

Abstract

The DNA sequence for the extracellular lignin peroxidase isozyme H2 fromPhanerochaete chrysosporium,obtained from cDNA clone λML-6, was synthesized by PCR and successfully expressed inEscherichia coliunder control of the T7 promoter. The portion of the cDNA encoding the signal peptide, not found in the mature native enzyme, was not included. Recombinated lignin peroxidase H2 (rLiPH2) was produced in inclusion bodies in an inactive form. Active enzyme was obtained by refolding with glutathione-mediated oxidation in a medium containing urea, Ca2+, and hemin. The recombinant enzyme had spectral characteristics and kinetic properties identical to that of native enzyme isolated fromP. chrysosporium.Surprisingly, rLiPH2, like the native enzyme, also exhibited some manganese peroxidase activity.