title: Transient increase of tryptophan fluorescence of enzyme caused by photoexcitation of ligand in luciferase-luciferin complex.
abstract: An experiment was proposed and accomplished that was based on the hypothesis of the dissociation of the luciferase-luciferin complex in photoexcitation. A pump-probe experiment was performed with the use of picosecond laser pulses and was based on the effect of quenching of enzyme tryptophan fluorescence caused by luciferin binding. A photoinduced increase of the tryptophan fluorescence intensity was detected. Experimental results were interpreted on the basis of the assumptions on photoinduced dissociation of the luciferin-luciferase complex and Forster energy transfer from tryptophan to luciferin. Under the assumption on the photoinduced dissociation and stationary quenching of tryptophan fluorescence the rate of propagation of the conformational changes in the protein caused by the complex dissociation was estimated to be >20 m/s.
authors.affiliation: Chemical Department, Moscow State University, Russia.
authors.lastname: Brovko LYu
authors.lastname: Cherednikova EYu
authors.lastname: Chikishev AYu
authors.forename: E I
authors.initials: EI
authors.lastname: Dementieva
authors.forename: N I
authors.initials: NI
authors.lastname: Koroteev
authors.forename: N N
authors.initials: NN
authors.lastname: Ugarova
mesh_terms: D004735:Energy Transfer; D049454:Firefly Luciferin / Q000737:chemistry* / Q000378:metabolism; D005453:Fluorescence; D008156:Luciferases / Q000737:chemistry* / Q000378:metabolism*; D008163:Luminescent Measurements; D013997:Time Factors; D014364:Tryptophan
chemical_list: D049454:Firefly Luciferin; D014364:Tryptophan; D008156:Luciferases