title: Signal and binding. I. Physico-chemical response to macromolecule-ligand interactions.
abstract: Obtaining a detailed knowledge about energetics of ligand-macromolecule interactions is a prerequisite for elucidation of the nature, behavior, and activities of the formed complexes. The most commonly used methods in characterizing molecular interactions are physico-chemical techniques based mainly on spectroscopic, calorimetric, hydrodynamic, etc., measurements. The major advantage of the physico-chemical methods is that they do not require large quantities of material and, if performed carefully, do not perturb examined reactions. Applications of several different physico-chemical approaches, commonly encountered in analyses of biochemical interactions, are here reviewed and discussed, using examples of simple binding reactions. It is stressed that without determination of the relationship between the measured signal and the total average degree of binding, the performed analysis of a single physico-chemical titration curve may provide only fitting parameters, instead of meaningful interaction parameters, already for the binding systems with only two ligand molecules. Some possible pitfalls in the analyses of single titration curves are discussed.
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, TX 77555-1053, USA; Department of Obstetrics and Gynecology, The University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, TX 77555-1053, USA; The Sealy Center for Structural Biology, Sealy Center for Cancer Cell Biology, The University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, TX 77555-1053, USA. Electronic address: wbujalow@utmb.edu.
authors.forename: Wlodzimierz
authors.initials: W
authors.lastname: Bujalowski
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, TX 77555-1053, USA; The Sealy Center for Structural Biology, Sealy Center for Cancer Cell Biology, The University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, TX 77555-1053, USA.
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Jezewska
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, TX 77555-1053, USA; The Sealy Center for Structural Biology, Sealy Center for Cancer Cell Biology, The University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, TX 77555-1053, USA.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Bujalowski
mesh_terms: D002627:Chemistry, Physical / Q000379:methods*; D008024:Ligands; D046911:Macromolecular Substances / Q000378:metabolism*
chemical_list: D008024:Ligands; D046911:Macromolecular Substances
keywords: Binding isotherms; Physico-chemical titrations; Thermodynamics