title: Electrochemistry of cytochrome P450 enzyme on nanoparticle-containing membrane-coated electrode and its applications for drug sensing.
abstract: In the current study, we describe an improved system to study the two-electron delivery reaction pathway of cytochrome P450, family 2, subfamily B, polypeptide 6 (CYP2B6) in vitro. In particular, a biocompatible film containing colloidal gold nanoparticles and chitosan was used to encapsulate CYP2B6 on an electrode. The electrocatalytic behaviors of CYP2B6 toward common drugs in the absence of NADHP-cytochrome P450 reductase as electron donor were studied. In an anaerobic solution, direct and reversible electron transfer between the electroactive heme center of CYP2B6 and the electrode was observed with a formal potential of -0.454 +/- 0.006 V at pH 7.4. In an air-saturated solution, an increase in the bioelectrocatalytic reduction current was observed after drug addition. The bioelectrocatalytic products were analyzed using high-performance liquid chromatography (HPLC) and electrospray ionization-mass spectrometry (ESI-MS). Both results confirmed that C-hydroxylation and heteroatom release were the main pathways for CYP2B6-mediated drug oxidation, similar to what occurred in vivo. The use of immobilized proteins in nanoparticle-containing films in drug biosensing was also demonstrated.
authors.affiliation: State Key Laboratory of Bioelectronics and Jiangsu Provincial Key Laboratory of Biomaterials and Biodevices, School of Chemistry and Chemical Engineering, Southeast University, Nanjing 210096, People's Republic of China. liusq@seu.edu.cn
authors.forename: Songqin
authors.initials: S
authors.lastname: Liu
authors.forename: Lei
authors.initials: L
authors.lastname: Peng
authors.forename: Xiaodi
authors.initials: X
authors.lastname: Yang
authors.forename: Yafeng
authors.initials: Y
authors.lastname: Wu
authors.forename: Lin
authors.initials: L
authors.lastname: He
mesh_terms: D001189:Aryl Hydrocarbon Hydroxylases / Q000737:chemistry* / Q000378:metabolism; D015374:Biosensing Techniques / Q000295:instrumentation*; D002244:Carbon / Q000737:chemistry; D002384:Catalysis; D048271:Chitosan / Q000737:chemistry; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D065702:Cytochrome P-450 CYP2B6; D004553:Electric Conductivity; D004563:Electrochemistry; D004566:Electrodes; D006046:Gold / Q000737:chemistry; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry*; D010089:Oxidoreductases, N-Demethylating / Q000737:chemistry* / Q000378:metabolism; D010100:Oxygen / Q000737:chemistry
chemical_list: D020099:Coated Materials, Biocompatible; D002244:Carbon; D006046:Gold; D048271:Chitosan; D001189:Aryl Hydrocarbon Hydroxylases; C585599:CYP2B6 protein, human; D065702:Cytochrome P-450 CYP2B6; D010089:Oxidoreductases, N-Demethylating; D010100:Oxygen