The local dynamics of the active site region of glycogen phosphorylase B.
The parameters characterizing the quenching of fluorescence emitted by the coenzyme (pyridoxal-5-phosphate) of phosphorylase b (EC 2.4.1.1) by anions are good indicators of conformational/dynamic changes at the active center. Reinvestigation of this quenching process resulted in a non-linear Stern-Volmer plot. This non-linearity is described by a simple kinetic model which assumes two parallel processes, one represented by bound and the second by free quencher molecules. Analysis of separate parts of the non-linear Stern-Volmer plot results in the values of rate constants for the bound and free quencher molecules as well as the value of dissociation constant of the anions.
Somogyi
B
B
Department of Biophysics, University Medical School of Pécs, Hungary.
Szarka
A
A
Lakos
Z
Z
D000818:Animals; D001665:Binding Sites; D002850:Chromatography, Gel; D007700:Kinetics; D008962:Models, Theoretical; D018482:Muscle, Skeletal / Q000201:enzymology*; D010763:Phosphorylase b / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D011817:Rabbits; D013050:Spectrometry, Fluorescence
D010763:Phosphorylase b