title: On the analysis of fluorimetric titration curves of purine nucleoside phosphorylase.
abstract: The steady-state fluorimetric titration curves for trimeric purine nucleoside phosphorylase (PNP) by two ligands, were analysed using the DynaFit program. Results of this analysis indicate that three binding sites of PNP molecule interact with each other and that the character of this interaction is different for both ligands. The DynaFit program is very useful in studies of oligomeric proteins, but for detection of non-interacting sites some independent tests are necessary.
authors.affiliation: Department of Biophysics, Institute of Experimental Physics, University of Warsaw, Zwirki i Wigury 93, 02-089 Warsaw, Poland.
authors.forename: Jan M
authors.initials: JM
authors.lastname: Antosiewicz
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Breer
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Bzowska
authors.forename: Beata
authors.initials: B
authors.lastname: Wielgus-Kutrowska
mesh_terms: D001665:Binding Sites; D006147:Guanine / Q000737:chemistry; D008024:Ligands; D011683:Purine-Nucleoside Phosphorylase / Q000737:chemistry*; D012984:Software; D013050:Spectrometry, Fluorescence; D013866:Thioguanine / Q000031:analogs & derivatives / Q000737:chemistry; D017186:Titrimetry
chemical_list: C541640:2-amino-9-(2-(phosphonomethoxy)ethyl)-6-sulfanylpurine; D008024:Ligands; D006147:Guanine; D011683:Purine-Nucleoside Phosphorylase; D013866:Thioguanine