On a revised mechanism of side product formation in the lignin peroxidase catalyzed oxidation of veratryl alcohol

The O-2-dependent formation of side products during the oxidation of veratr yl alcohol (VA) by lignin peroxidase has previously been proposed to start with the attack of H2O on the VA radical cation (VA(.+)). This initial reac tion is unlikely since it would also lead to side product formation in the absence of O-2, which is not the case. In the current mechanism VA(.+) reac ts first with O-2, whereafter H2O attacks. Furthermore, this paper describe s an alternative explanation for the inhibitory effect of Mn2+ on VA side p roduct formation. It is proposed that Mn2+ reduces reactive intermediates b ack to VA. (C) 2001 Federation of European Biochemical Societies, Published by Elsevier Science B.V. All rights reserved.