Expression of Pleurotus eryngii aryl-alcohol oxidase in Aspergillus nidulans: Purification and characterization of the recombinant enzyme

Aryl-alcohol oxidase (AAO) is an extracellular flavoenzyme involved in lign in biodegradation by some white-rot fungi. The enzyme catalyzes the extrace llular oxidation of aromatic alcohols to the corresponding aldehydes. The e lectron acceptor is molecular oxygen yielding H2O2 as the product. Herein w e describe, for the first time, the expression of AAO from Pleurotus eryngi i in the ascomycete Aspergillus nidulans. The activity of the recombinant e nzyme in A. nidulans cultures is much higher than found in the extracellula r fluid of P. eryngii. The recombinant enzyme showed the same molecular mas s, pi and catalytic properties as that of the mature protein secreted by P. eryngii. The enzymic properties are also similar to those reported from ot her Pleurotus and Bjerkandera species. (C) 2001 Elsevier Science B.V. All r ights reserved.