LIGHT-INDUCED FREE RADICALS IN FMN AND FLAVOPROTEIN ENZYMES

Abstract
Experiments are reported which indicate that flavin prosthetic groups and flavoprotein oxidation-reduction enzymes readily form free radicals when exposed to ordinary intensities of visible light. The light-induced free radicals appear to be identical with those ordinarily formed as intermediates in the oxidation-reduction process carried out by these components. This effect provides a mechanism which can mediate the influence of light on cellular oxidation-reduction. Since flavoprotein enzymes participate in a wide range of metabolic systems, the evidence also indicates that the observed effects of light on cellular processes is probably of quite general significance.