The photochemical action spectrum of the microsomal ethanol oxidizing system.

The inhibition of the microsomal ethanol oxidizing system (MEOS) by carbon monoxide (CO) can be reversed by illumination with lights of differing wavelengths. The authors determined the efficiency of this reversal as a function of the illuminating light. Maximum efficiency was obtained in the wavelength band around 440-450 nm, which is near the absorption of the reduced cytochrome-P-450-carbon monoxide complex. When the experiment was repeated with microsomes prepared from ethanol-fed rats, the wavelength for maximum efficiency shifted towards higher values.