Marden M C, Hoa G H
Arch Biochem Biophys. 1987 Feb 15;253(1):100-7. doi: 10.1016/0003-9861(87)90642-4.
The spin equilibrium of two bacterial cytochrome P-450 enzymes are compared by their visible spectra versus temperature and pressure. P-450 from Pseudomonas linalool shows a much weaker dependence on pressure than P-450 from P. putida which has camphor as substrate. The linalool system denatures at a higher pressure (3 kbar) than the camphor system (1 kbar) and shows a weaker dependence on external solvent conditions. The camphor system shows evidence of the binding of a second substrate molecule which reverses the effect of the first on the spin equilibrium. A model involving two substrate molecules is an alternative explanation of the apparent saturation with camphor of the spin equilibrium.
