Resonance Raman Detection of the Hydroperoxo Intermediate in the Cytochrome P450 Enzymatic Cycle
Format of Original
American Chemical Society
Journal of the American Chemical Society
Original Item ID
The resonance Raman spectra of the hydroperoxo complex of camphor-bound CYP101 have been obtained by cryoradiolytic reduction of the oxygenated ferrous form that had been rapidly frozen in water/glycerol frozen solution; EPR spectroscopy was employed to confirm the identity of the trapped intermediate. The ν(O−O) mode, appearing at 799 cm-1, is observed for the first time in a peroxo-heme adduct. It is assigned unambiguously by employing isotopomeric mixtures of oxygen gas containing 50% 16O18O, confirming the presence of an intact O−O fragment. The ν(Fe−O) mode is observed at 559 cm-1 (H2O). Furthermore, both modes shift down by 3 cm-1, documenting the formulation as a hydroperoxo complex, in agreement with EPR data.
Mak, Piotr J.; Denisov, Ilia G.; Victoria, Doreen; Makris, Thomas M.; Deng, Tianjing; Sligar, Stephen G.; and Kincaid, James R., "Resonance Raman Detection of the Hydroperoxo Intermediate in the Cytochrome P450 Enzymatic Cycle" (2007). Chemistry Faculty Research and Publications. 405.