Effect of Mn(II) on reactions catalyzed by lignin peroxidase from Phanerochaete chrysosporium

The effect of manganese on lignin peroxidase activity was studied. The enzyme was produced with a new process using an air-lift-type reactor. The experiments were performed with veratryl alcohol and a dimeric lignin model compound. It was shown that when Mn(II).lactate complex was present the amount of veratraldehyde formed and the uptake of oxygen were significantly enhanced during the aerobic oxidation of veratryl alcohol. A similar effect can be obtained with superoxide dismutase. These results strongly suggest that the superoxide anion can occur during the reaction; its scavenging by Mn(II) or superoxide dismutase generates H2O2. In contrast, no evidence for the formation of superoxide anion was found during oxidation of the lignin model, compound veratrylglycerol-beta-guaiacyl ether.