Different fungal manganese-oxidizing peroxidases: a comparison between Bjerkandera sp and Phanerochaete chrysosporium

Two manganese-oxidizing peroxidases differing in glycosylation degree were purified from fermenter cultures of Bjerkandera sp. They were characterized and compared with the three manganese-oxidizing peroxidase isoenzymes obta ined from the well-known ligninolytic fungus Phanerochaete chrysosporium. A ll the enzymes showed similar molecular masses but those from P. chrysospor ium had less acidic isoelectric point. Moreover, the latter strictly requir ed Mn2+ to oxidize phenolic substrates whereas the Bjerkandera peroxidases had both Mn-mediated and Mn-independent activity on phenolic and non-phenol ic aromatic substrates. Taking into account these results, and those report ed for Bjerkandera andusta and different Pleurotus species, we concluded th at two different types of Mn2+-oxidizing peroxidases are secreted by lignin olytic fungi. (C) 2000 Elsevier Science B.V. All rights reserved.