Isoenzyme multiplicity and characterization of recombinant manganese peroxidases from Ceriporiopsis subvermispora and Phanerochaete chrysosporium.

We expressed cDNAs coding for manganese peroxidases (MnPs) from the basidiomycetes Ceriporiopsis subvermispora (MnP1) and Phanerochaete chrysosporium (H4) under control of the alpha-amylase promoter from Aspergillus oryzae in Aspergillus nidulans. The recombinant proteins (rMnP1 and rH4) were expressed at similar levels and had molecular masses, both before and after deglycosylation, that were the same as those described for the MnPs isolated from the corresponding parental strains. Isoelectric focusing (IEF) analysis of rH4 revealed several isoforms with pIs between 4.83 and 4.06, and one of these pIs coincided with the pI described for H4 isolated from P. chrysosporium (pI 4.6). IEF of rMnP1 resolved four isoenzymes with pIs between 3.45 and 3.15, and the pattern closely resembled the pattern observed with MnPs isolated from C. subvermispora grown in solid-state cultures. We compared the abilities of recombinant MnPs to use various substrates and found that rH4 could oxidize o-dianisidine and p-anisidine without externally added manganese, a property not previously reported for this MnP isoenzyme from P. chrysosporium.