title: Antibody-mediated modification of the binding properties of a protein related to galactose transport.
abstract: A galactose-binding protein related to the mglP transport system of Escherichia coli increases its affinity and binding capacity for the substrate when exposed to both d-galactose and specific antibodies. For this increase to occur, the binding protein has to be in contact with d-galactose for at least 2 min prior to the addition of the antibodies. This reaction was used to show that other substrates of the mglP transport system compete with galactose for a site(s) of the binding protein and that the degree of competition is comparable to that observed in vivo. A model for substrate translocation is presented postulating a cellular component that can induce conformational changes in the galactose-binding protein similar to those caused by antibodies.
mesh_terms: D000818:Animals; D000906:Antibodies / Q000494:pharmacology*; D000918:Antibody Specificity; D001426:Bacterial Proteins / Q000032:analysis / Q000378:metabolism*; D001693:Biological Transport, Active; D002869:Chromosome Aberrations; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology / Q000276:immunology* / Q000378:metabolism; D005690:Galactose / Q000378:metabolism*; D007106:Immune Sera; D007136:Immunoglobulins; D007700:Kinetics; D026901:Membrane Transport Proteins / Q000032:analysis; D009154:Mutation; D011485:Protein Binding / Q000187:drug effects*; D011817:Rabbits / Q000276:immunology; D014316:Tritium
chemical_list: D000906:Antibodies; D001426:Bacterial Proteins; D007106:Immune Sera; D007136:Immunoglobulins; D026901:Membrane Transport Proteins; D014316:Tritium; D005690:Galactose