title: [The principles of analysis on multicomponent fluorescence spectra of proteins. Temperature and pH-induced transitions in tetrameric melittin].
abstract: Structural transitions in the tetrameric melittin from bee venom in 2 M KCl induced by variations of pH (from 0.7 to 12.0) and temperature (from 2 to 95 degrees C) have been studied. The pH and temperature ranges of structural changes and the zones of emission quenching of discerning tryptophan classes were revealed. The analysis of the temperature dependence of monotonic changes of spectral maximum positions and relative fluorescence yields allowed one to discriminate the zone of structural transitions in the tetramer from that of temperature quenching due to the thermal activation of fluorophore collisions with neighboring quenching groups in protein. Based on the new and earlier published results, some advantages and modes of using the method of component analysis of protein tryptophan spectra were summarized to determine the main characteristics of physicochemical transitions in proteins.
authors.forename: V I
authors.initials: VI
authors.lastname: Emel'ianenko
authors.forename: V M
authors.initials: VM
authors.lastname: Grishchenko
authors.forename: E A
authors.initials: EA
authors.lastname: Burshteĭn
mesh_terms: D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D008555:Melitten / Q000737:chemistry*; D011189:Potassium Chloride / Q000737:chemistry*; D020836:Protein Structure, Quaternary; D013050:Spectrometry, Fluorescence; D014364:Tryptophan / Q000737:chemistry*
chemical_list: D008555:Melitten; D011189:Potassium Chloride; D014364:Tryptophan