INSERM-INRA, U310, Institut de Biologie Physico-Chimique, Paris, France.
Absorbance and fluorescence spectra of bacterial cytochrome P-450cam and cytochrome P-450lin have been studied as a function of pressure. These pressure-induced spectral perturbations fall into two categories, which are interpreted as resulting from denaturation domains and are discussed in terms of protein structural dynamics. The results presented herein support a view that these two bacterial cytochromes have large structural differences and suggest a picture in which the gellike cortex of each protein may play an essential role in stability and function.