Ion sensitivity of the light reaction catalyzed by enzyme preparations from Photobacterium phosphoreum

Abstract

Cations, especially divalent ones, increase the intensity of the light flash, obtained by adding FMNH to luciferase preparations containing palmital. Besides, they cause a more rapid decay of the light reaction. Probably, the effect is due to inhibition of the oxidation of FMNH independent of the light reaction by some oxidizing substance. This substance may oxidize free as well as luciferase bound FMNH. No influence of ions on the light reaction proper could be found. The experiments suggest the conclusion that FMNH is not bound to the luciferase molecule via the phosphate group.