ISOLATION OF AN EXTRACELLULAR MN-DEPENDENT ENZYME MINERALIZING MELANOIDINS FROM THE WHITE-ROT FUNGUS TRAMETES-VERSICOLOR

Culture filtrates of Trametes versicolor exhibits a mineralizing activity on melanoidins (i.e., Maillard polymers) used as model compounds for biorecalcitrant polymers and synthetic humic acids. This activity was strongly enhanced in the presence of Mn2+ (0.1 mM), and the major Mn2+-dependent enzyme system which catalyzes the mineralization was isolated. This enzyme system requires O2, has a molecular mass of 47 kDa estimated from SDS-PAGE, oxidizes NADH in the absence of H2O2, but mineralizes melanoidins in the absence of H2O2 or NADH.