THE INFLUENCE OF C=O GROUP ON PHOTODEACTIVATION PROCESSES IN TRYPTOPHAN

It has been found that action of the light in a longer wavelength regi on of the tryptophan triplet-triplet absorption in polar glass at 77 K leads to a reversible decrease of the phosphorescence intensity. This effect is accompanied by decreasing of a lifetime for phosphorescent state. It has been proved that a reversible decrease of tryptophan pho sphorescence is a result of intermolecular process connected with deac tivation of the triplet T-1-state by C=O fragment of the carboxyl grou p. It seems that the reversible decrease of phosphorescence might be c onnected with a sufficiently fast process, which competes with a vibro nical T-2-->T-1 relaxation.