Fluorescence and protein structure: XI. Fluorescence quenching by disulfide and sulfhydryl groups

摘要: Abstract 1. 1.|Compounds were synthesized as models for quenching of tryptophan and tyrosine fluorescence in proteins. Bis-indole-3-methylene disulfide, bis-4-methoxybenzyl disulfide their corresponding reduced, sulfhydryl derivatives extremely low fluorescence. The loss is ascribed to internal by the groups. 2. 2.|Similar results obtained l -cystinyl-bis- -tyrosine, HOOC(CH 2 ) -S-S-Cys-Tyr, ribonuclease-(SCH CH COOH) 8 , reduced or carboxy-methylated products. That is, group strongly quenched fluorescence; less. 3. 3.|The mechanism has not been established but several common pathways rejected. most probable seems be an short-range interaction between aromatic ring sulfur atoms that facilitates a vibrational dissipation excitation energy.