[Changes in the state of tryptophan residues in T4 phage lysozyme during binding to a competitive inhibitor]. / Izmenenie sostoianiia ostatkov triptofana v lizotsime faga T4 pri sviazyvanii konkurentnogo ingibitora.

The analysis of the intrinsic fluorescence parameters of T4 phage lysozyme in free state and in complex with inhibitor--disaccharide-tetrapeptide from the E. coli cell wall has been carried out. A comparison of the fluorescence changes with the results obtained by difference spectrophotometry and with the data of Elwell and Schellman on the intrinsic fluorescence of wild type WT and mutant eRI T4 phage lysozymes and a consideration of the three dimensional structure of the protein allows to represent the protein fluorescence parameters as a sum of contributions of the individual tryptophan residues. According to the proposed scheme Trp-126 does not emit neither in the free protein nor in the complex; the fluorescence parameters of Trp-158 (lambda m 332 nm, q = 0.27) are not affected by binding of the inhibitor, but all the fluorescence changes are due to the rise of the quantum yield (from 0.135 to 0.315) and the blue shift (from 332 to 328 nm) of the fluorescence of Trp-138.