title: Specificity in protein-ligand interactions: a model from estrone-antiserum binding.
abstract: The specificity of protein-ligand interactions has been investigated using the binding of structurally related steroids to a polyclonal anti-estrone antiserum as a model. The cross-reaction profile of the native antiserum was compared with profiles obtained for the same antiserum preparation following affinity separation on stationary phases carrying structures which mimic parts of the antigen molecule: the coupling bridge, the A ring of the estrogen and the carrier protein. This fractionation produced antibody mixtures with different specificities from that observed for the pre-affinity antiserum. The changes in specificity observed and, more importantly, the direction of each variation detected, suggested the basis for a description of the nature of molecular recognition of small ligands by a protein as discrete rather than continuous. This methodology has revealed some recognition mechanisms.
authors.affiliation: Università di Pisa, Dipartimento di Scienze Anatomiche, Fisiologiche e delle Produzioni Animali, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Podestà
authors.forename: G
authors.initials: G
authors.lastname: Montagnoli
mesh_terms: D000818:Animals; D000937:Antigen-Antibody Reactions; D002846:Chromatography, Affinity; D003429:Cross Reactions; D004970:Estrone / Q000378:metabolism*; D007106:Immune Sera / Q000378:metabolism*; D008297:Male; D011817:Rabbits; D011869:Radioligand Assay
chemical_list: D007106:Immune Sera; D004970:Estrone