title: Role of Quinones in Electron Transfer of PQQ-Glucose Dehydrogenase Anodes—Mediation or Orientation Effect.
abstract: In this study, the influence of two quinones (1,2- and 1,4-benzoquinone) on the operation and mechanism of electron transfer in PQQ-dependent glucose dehydrogenase (PQQ-sGDH) anodes has been determined. Benzoquinones were experimentally explored as mediators present in the electrolyte. The electrochemical performance of the PQQ-sGDH anodes with and without the mediators was examined and for the first time molecular docking simulations were used to gain a fundamental understanding to explain the role of the mediator molecules in the design and operation of the enzymatic electrodes. It was proposed that the higher performance of the PQQ-sGDH anodes in the presence of 1,2- and 1,4-benzoquinones introduced in the solution is due to the shorter distance between these molecules and PQQ in the enzymatic molecule. It was also hypothesized that when 1,4-benzoquinone is adsorbed on a carbon support, it would play the dual role of a mediator and an orienting agent. At the same time, when 1,2-benzoquinone and ubiquinone are adsorbed on the electrode surface, the enzyme would transfer the electrons directly to the support, and these molecules would primarily play the role of an orienting agent.
authors.affiliation: †Chemical and Biological Engineering Department, Center for Micro-engineering Materials, University of New Mexico, Albuquerque, New Mexico 87131, United States.
authors.forename: Sofia
authors.initials: S
authors.lastname: Babanova
authors.affiliation: †Chemical and Biological Engineering Department, Center for Micro-engineering Materials, University of New Mexico, Albuquerque, New Mexico 87131, United States.|‡Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States.
authors.forename: Ivana
authors.initials: I
authors.lastname: Matanovic
authors.affiliation: †Chemical and Biological Engineering Department, Center for Micro-engineering Materials, University of New Mexico, Albuquerque, New Mexico 87131, United States.
authors.forename: Madelaine Seow
authors.initials: MS
authors.lastname: Chavez
authors.affiliation: †Chemical and Biological Engineering Department, Center for Micro-engineering Materials, University of New Mexico, Albuquerque, New Mexico 87131, United States.
authors.forename: Plamen
authors.initials: P
authors.lastname: Atanassov
mesh_terms: D016954:Acinetobacter calcoaceticus / Q000201:enzymology* / Q000378:metabolism; D016227:Benzoquinones / Q000378:metabolism*; D015374:Biosensing Techniques; D004579:Electron Transport; D004800:Enzymes, Immobilized / Q000378:metabolism; D005948:Glucose Dehydrogenases / Q000378:metabolism*; D062105:Molecular Docking Simulation
chemical_list: D016227:Benzoquinones; D004800:Enzymes, Immobilized; D005948:Glucose Dehydrogenases; C033955:glucose dehydrogenase (pyrroloquinoline-quinone); C025225:2-benzoquinone