STUDEIS OF OXIDATION STATE OF PARTIALLY PURIFIED ADRENAL CORTEX MITOCHONDRIAL CYTOCHROME P-450 AND DIFFERENCE SPECTRA INDUCED BY DEOXYCORTICOSTERONE AND METOPIRONE

Cytochrome P-450 prepared from extracts of adrenal gland cortex mitochondrial acetone powder exists in the oxidized state as it will not complex with carbon monoxide. Both deoxycorticosterone and Metopirone will induce spectra in the preparation in the absence of oxygen and reductase components. Metopirone displaces the deoxycorticosterone-induced difference spectrum of the cytochrome P-450 preparation, but excess deoxycorticosterone does not influence the Metopirone-induced spectrum suggesting different complexing mechanisms for the two compounds. The observations are consistent with the concept that the steroid-induced spectrum is the result of a direct complexing with ferric cytochrome P-450, or a closely associated companion pigment dependent upon the ferric state of cytochrome P-450. Current observations indicate experimentally separable reaction steps in the overall system of 11β-hydroxylation. © 1969.