Purification and characterization of novel manganese peroxidase from Trichoderma parestonica and its bio-conversion study of toxic arylamine

Trichoderma parestonica is a novel source of manganese peroxidase (MnP), [E.C.1.11.1.13] enzyme. The following was the sequence in which T. parestonica induced the production of MnP in the liquid culture medium: rice husk, corncob, sawdust, coir-dust and dried luffa on days 3, 4, 5, 2 and 3, respectively. The molecular weight of the enzyme was found to be 45kDa, determined from SDS-PAGE analysis which was further confirmed by mass analysis and was found to be 51.9kDa. Enzyme characterization parameters like optimum pH, temperature, Km, K-cat and catalytic efficiency are 5, 20 degrees C, 0.014mM (for Mn2+) and 0.028mM (for H2O2), 23.9 S-1 and 1.7 mu M-1 S-1 respectively. Effect of various metal ions, such as bivalent Copper(Cu), Cobalt(Co), Mercury(Hg), Nickel(Ni), Cadmium(Cd), trivalent Chromium(Cr), Iron(Fe), Tetra-valent cerium(Ce), Penta-valent vanadium(V) and hexavalent molybdenum(Mo) the enzyme-catalyzed steady-state velocity was studied. The inhibition constant and nature of inhibition by these metal ions were determined. In the current investigation, MnP catalytic activities demonstrated that it could effectively catalyze the oxidation of phenols, aromatic amines and wastewater treatment. This communication suggested potential pathways for aromatic amine bioconversion mediated by MnP