Abstract

This is a review of recent progress in developing biocatalytic reactions involving two major groups of phenol oxidases, viz., laccases (benzenediol:oxygen oxidoreductase E.C. 1.10.13.2) and polyphenol oxidases (phenol: oxygen oxidoreductase, E.C. 1.14.18.1, also known as tyrosinase). Oxidases catalyse reactions involving direct activation of oxygen, and within this group, the multi-copper oxidases catalyse the four-electron reduction of oxygen to water with the concomitant one-electron oxidation of a substrate. Such reactions, applied in biocatalytic systems, provide effective methods to achieve oxyfunctionalisation, (particularly asymmetric oxyfunctionalisation reactions) and routes to controlled and predictable formation of oxy- and hydroxylated products, and polymers. The review includes discussion of the characteristics of these enzymes which are of relevance to their application as biocatalysts.

Keywords: Laccases, Phenol Oxidases, oxyfunctionalisation, hydroxylated products, biocatalysts