Electrochemical generation of a high-valent state of cytochrome P450.
Cyclic voltammetry performed at rapid scan rates on cytochrome P450 from Pseudomonas putida (P450CAM) in didodecyldimethylammonium bromide (DDAB) films on graphite electrodes revealed a couple (E) at 830mV (vs Ag/AgCl). E was not significantly observed at scan rates less than 30V/s at room temperature, suggesting that the oxidized species is unstable. The lifetime of E could be prolonged at 4 degrees C, which allowed reversible access to E at scan rates as low as 1V/s. E was found to be sensitive to imidazole in solution and to variations in pH, suggesting that the redox reaction is occurring at the metal center (i.e., Fe(IV/III)). Electrolysis reactions with different P450 substrates revealed that the electrochemically generated high-valent species is able to convert thioanisole to methyl phenyl sulfoxide.
Udit
Andrew K
AK
Department of Chemistry, Occidental College, 1600 Campus Road, Los Angeles, CA 91030, USA. udit@oxy.edu
Hill
Michael G
MG
Gray
Harry B
HB
D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry*; D004563:Electrochemistry; D005290:Ferric Compounds / Q000737:chemistry* / Q000378:metabolism; D007501:Iron / Q000737:chemistry* / Q000378:metabolism; D010084:Oxidation-Reduction; D016958:Pseudomonas putida / Q000201:enzymology / Q000378:metabolism; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D013440:Sulfides / Q000737:chemistry; D013454:Sulfoxides / Q000737:chemistry
D005290:Ferric Compounds; D000644:Quaternary Ammonium Compounds; D013440:Sulfides; D013454:Sulfoxides; C417240:methyl phenyl sulfoxide; C046112:didodecyldimethylammonium; C066317:ferryl iron; D003577:Cytochrome P-450 Enzyme System; C093850:methylphenylsulfide; D007501:Iron