pH-Dependence of Manganese (II) Oxidation Reaction by Novel Wild-Type and Mutants Recombinant <i>Phlebia radiata</i> Manganese Peroxidase 3 (rPr-MnP3) Enzymes

The goal of this study was to determine whether mutation the Mn-binding site wild-type recombinant Phlebia radiata manganese peroxidase 3 affected pH-dependence kinetic parameters. pH range investigated 2.5 – 12.0. catalytic efficiency mutant enzymes at high and low in comparison using standard rPr-MnP3 protocol. Wild-type MnP3 enzyme showed optimal activity with Mn (II) as substrate 5.0 remained moderately active (approximately 40%) 6.0 - 9.0. mutants’ maximum ranged between 5.5 8.0. mutants exhibited a similar profile optimum 3.0 for ABTS oxidation. Mutation has severely decreased oxidation 5.0. enhanced affinity alkaline more catalysis than ever reported any Manganese Peroxidase. This reveals that higher pH, can function alternative ligands does not have an absolutely obligate requirement all carboxylate ligand set. These results further strongly confirm Mn2+ binding is only productive