Back to Search
Start Over
P450 versus P420: correlation between cyclic voltammetry and visible absorption spectroscopy of the immobilized heme domain of the cytochrome P450 BM3
- Publication Year :
- 2008
-
Abstract
- Cyclic voltabsorptometry is used for the first time to distinguish and characterize electrochemically the active (P450) and inactive (P420) forms of cytochromes P450 immobilized on an electrode during voltammetry experiments. This was achieved by using the heme domain (BMP) of the bacterial cytochrome P450 BM3 from Bacillus megaterium (CYP102A1) immobilized on mesopouros tin-oxide (SnO2) electrodes. We demonstrate that the formation of either the P450 form or the P420 one can be obtained by modifying the mesoporous electrode surface with polycations with different properties such as polyethylenimmine (PEI) and polydiallyldimethylammonium chloride (PDDA). Potential step spectroelectrochemistry allowed measurement of reduction potentials of the active P450 form. Values of -0.39+/-0.01 V and -0.58+/-0.01 V (both versus Ag/AgCl) were calculated for the active P450 form immobilized on the BMP/PDDA-SnO2 and BMP/PEI-SnO2 electrodes, respectively. The cyclic voltabsorptometric experiments showed how, when both the active and inactive forms are present on the PEI film, the inactive P420 species tends to dominate the cyclic voltammetric signal.
- Subjects :
- Absorption spectroscopy
Inorganic chemistry
Cytochrome P450
Heme
Chloride
chemistry.chemical_compound
Cytochrome P-450 Enzyme System
Materials Chemistry
medicine
Electrochemistry
Physical and Theoretical Chemistry
Electrodes
Voltammetry
Bacillus megaterium
biology
Spectrum Analysis
Titrimetry
Tin Compounds
biology.organism_classification
Surfaces, Coatings and Films
Oxygen
Quaternary Ammonium Compounds
chemistry
Electrode
Cytochromes
Imines
Polyethylenes
Cyclic voltammetry
Mesoporous material
medicine.drug
Subjects
Details
- Language :
- English
- Database :
- OpenAIRE
- Accession number :
- edsair.doi.dedup.....823dc06a9feb8ba62a62f5f9dff2446b