The role of the hydrophobic bonding in P-450 and the effect of organic compounds on the conversion of P-450 to P-420.
Abstract The conversion of cytochrome P-450 to P-420 by organic solvents was studied. The transition concentrations of ureas used for conversion of P-450 to P-420 were, in decreasing order: urea, N -methylurea, 1,1-dimethylurea, ethylurea, tetramethylurea, 1,3-diethylurea. Similar results were obtained with amides. The transition concentrations of anilines and phenols closely paralleled the π values of the organic compounds. To maintain the structure which gives P-450 its unusual properties in comparison with other known hemoproteins, the hydrophobic bonding in P-450 appears to play an important role in that it binds the heme plane to the apoprotein.