Inhibitor binding studies on ascorbate oxidase

The characteristic features of the plant multicopper enzyme ascorbate oxidase are described, together with the current knowledge about its catalytic mechanism and substrate specificity. A variety of small anionic inhibitors have been used as spectroscopic probes for the enzyme metal sites, but recently interest has arisen for a new type of phenolic inhibitors which act competitively against ascorbate. These simple phenolic compounds can bind to the enzyme in the same pocket near type 1 copper as the substrate ascorbate binds, as shown by docking and molecular mechanics computations. (C) 1999 Elsevier Science S.A. All rights reserved.