Kinetic Properties of Laccase and Ascorbate Oxidase

Numerous studies concerning the catal5rtic and binding properties of the blue oxidases are well documented in the formerly mentioned reviews (see, for example, for laccase (10), for ascorbate oxidase (.19), and for ceruloplasmin (26)). Important data, concentrating on laccase and ascorbate oxidase only, are summarized here. 

Results from steady-state kinetics for laccase and ascorbate oxidase are given in Table VII. Listed are, and values at different pH values. The values indicate the low limit of the bimolecu- 

A ping-pong di Theorell-Chance mechanism has been deduced for tree laccase from steady-state kinetics (123). This mechanism is characterized by the sequential entry of the two substrates and the immediate 

Steady-State Kinetics of Laccase and Ascorbate Oxidase 

The anaerobic reduction of the trinuclear copper species monitored by the bleaching of the 330-nm band, the reappearance of the 600-nm band, and the disappearance of the type-2 EPR signal appear to be multiphasic processes in most cases. For fungal laccase, the process is monophasic with a unimolecular rate constant of 1.0 sec (225). Tree laccase with hydroquinone as a substrate (224) displays a pH depen- 

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