Direct electron transfer of cellobiose dehydrogenase from various biological origins at gold and graphite electrodes

Direct electron transfer was observed for cellobiose dehydrogenases (CDH) from three different fungi, viz. CDH from Phnerochaete chrysosporium, Sclerotium rolfsii and Humicola insolens, in the presence of cellobiose when the enzymes were adsorbed on graphite electrodes. The redox wave of the heme cofactor of CDH could be demonstrated on thiol modified gold electrodes using cyclic voltammetry for Phanerochaete CDH and Humicola CDH; however, the electrocatalytic current for cellobiose oxidation could only be registered for Phanerochaete CDH. (C) 2001 Elsevier Science B.V. All rights reserved.