Investigation of the orientation of Myriococcum thermophilum Cellobiose Dehydrogenase (MtCDH) immobilized on graphite electrodes

Abstract: Orientation of Myriococcum thermophilum Cellobiose Dehydrogenase (MtCDH) immobilized on spectroscopic graphite electrodes has been investigated electrochemically through flow injection analysis in order to obtain more information about the DET efficiency of this enzyme. The effect of applied potential and the long term stability of the modified electrodes were determined, as well as the bioelectrocatalytic current response with lactose as substrate was investigated by amperometric flow injection measurements in both direct and mediated electron transfer mode, with 1,4-benzoquinone as mediator. The effect of immobilization method on enzyme orientation was tested, and the assumption regarding orientation of MtCDH was accomplished by involving papain as restriction enzyme for cutting CDH molecules both in solution and on graphite electrodes.