title: Electroactive multilayer assemblies of bilirubin oxidase and human cytochrome C mutants: insight in formation and kinetic behavior.
abstract: Here, we report on cytochrome c/bilirubin oxidase multilayer electrodes with different cytochrome c (cyt c) forms including mutant forms of human cyt c, which exhibit different reaction rates with bilirubin oxidase (BOD) in solution. The multilayer formation via the layer-by-layer technique and the kinetic behavior of the mono (only cyt c) and biprotein (cyt c and BOD) multilayer systems are studied by SPR and cyclic voltammetry. For the layer construction, sulfonated polyaniline is used. The only cyt c containing multilayer electrodes show that the quantity of deposited protein and the kinetic behavior depend on the cyt c form incorporated. In the case of the biprotein multilayer with BOD, it is demonstrated that the catalytic signal chain from the electrode via cyt c to BOD and oxygen can be established with all chosen cyt c forms. However, the magnitude of the catalytic current as well as the kinetic behavior differ significantly. We conclude that the different cytochrome c forms affect three parameters, identified here, to be important for the functionality of the multilayer system: the amount of molecules per layer, which can be immobilized on the electrodes, the cyt c self-exchange rate, and the rate constant for the reaction with BOD.
authors.affiliation: Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14424 Potsdam-Golm, Germany.
authors.forename: Franziska
authors.initials: F
authors.lastname: Wegerich
authors.forename: Paola
authors.initials: P
authors.lastname: Turano
authors.forename: Marco
authors.initials: M
authors.lastname: Allegrozzi
authors.forename: Helmuth
authors.initials: H
authors.lastname: Möhwald
authors.forename: Fred
authors.initials: F
authors.lastname: Lisdat
mesh_terms: D045304:Cytochromes c / Q000737:chemistry* / Q000235:genetics; D004563:Electrochemistry; D004566:Electrodes; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D009154:Mutation; D044925:Oxidoreductases Acting on CH-CH Group Donors / Q000737:chemistry*; D017433:Protein Structure, Secondary
chemical_list: D045304:Cytochromes c; D044925:Oxidoreductases Acting on CH-CH Group Donors; C042401:bilirubin oxidase