Coriolus versicolor Laccase Catalyzes the Decarboxylation of 2-(4-Hydroxyphenyl)-glycine and 4-Hydroxymandelic Acid

Laccase (benzenediol: oxygen oxidoreductase, EC 1.10.3.2) has been found in some fungal strains belonging to various classes. The enzyme generally catalyzes the removal of hydrogen from phenolic hydroxyl groups or aromatic amino groups using molecular oxygen as a primary electron acceptor to give radicals, which undergo free-radical additions and related reactions to give various products. During the investigation on a laccase from the fungus Coriolus versicolor , we found that the enzyme catalyzed the conversion of 2-(4-hydroxyphenyl)glycine (HPG) or 4-hydroxymandelic acid (HMA) to 4-hydroxybenzaldehyde (HBA), which was a single product from either substrate and was not converted further. In this communication, we report a stoichiometric study on the new type of decarboxylation reactions catalyzed by laccase.