Photoinduced enhancement of the tryptophan fluorescence of the enzyme in the luciferase-luciferin complex

An experiment providing evidence in support of the hypothesis that the biol uminescent reaction is dissociative in character was proposed and carried o ut. The processes occurring in the native bioluminescent system were modell ed by the luciferase-luciferin complex. The experiment was performed in acc ordance with the pump-and-probe scheme involving probing by picosecond lase r pulses and was based on the steady-state quenching of the intrinsic trypt ophan fluorescence of luciferase when the latter is bound in a complex with luciferin, An increase in the intensity of the tr;tryptophan fluorescence on photoexcitation of luciferin was regarded as confirmation of the hypothe sis of the dissociation of the complex and it made it possible to estimate the rate of propagation of the corresponding conformational changes through the protein molecule.