Detection of a high-barrier conformational change in the active site of cytochrome P450cam upon binding of putidaredoxin.

ABSTRACT: The orientation of the substrate camphor in the active site of reduced CO-bound cytochrome P450cam (CYP101) as a function of reduced putidaredoxin (Pdxr) addition has been examined by NMR using perdeuterated CYP101 and perdeuterated Pdx as well as isotopically labeled d-camphor. This permits the 1H resonances of CYP101-bound camphor to be observed without interference from the signals of CYP101 or Pdx and confirms assignments of the methyl signals of camphor in the bound form. The Cys4Fe2S2 ferredoxin Pdx is the physiological redox partner and effector of CYP101. The addition of Pdx to the reduced CYP101-camphor-CO complex results in a conformational selection that is slow on the chemical shift time scale with spectral effects observed primarily at the 8-CH3 group of the camphor. The camph

SUBMITTER: Wei JY 

PROVIDER: S-EPMC1661779 | biostudies-literature | 2005 May

REPOSITORIES: biostudies-literature