title: Dynamical structure of the antibody combining site as studied by 1H-15N shift correlation NMR spectroscopy.
abstract: The Fv fragment, which is a smallest antigen-binding unit of immunoglobulin, has been used for a 1H-15N shift correlation NMR study of the dynamical structure of the antibody combining site. Fv has been prepared by clostripain digestion of a mouse anti-dansyl IgG2a monoclonal antibody that lacks the entire CH1 domain. We have previously reported that of the six hypervariable regions, three each from the heavy chain (H1, H2, and H3) and the light chain (L1, L2, and L3), H3 is primarily responsible for the antigen binding in the anti-dansyl Fv fragment. The backbone amide nitrogens of all non-proline amino acid residues in H3 have been multiply labeled with 15N. [15N]T2 relaxation times and hydrogen-deuterium exchange rates of the amide groups of the main chain were measured in the absence and presence of epsilon-dansyl-L-lysine (DNS-Lys). It has been shown that (1) in the absence of DNS-Lys H3 displays a significant degree of internal motion and (2) antigen binding induces a significant change in the dynamical structure of H3.
authors.affiliation: Faculty of Pharmaceutical Sciences, University of Tokyo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Takahashi
authors.forename: E
authors.initials: E
authors.lastname: Suzuki
authors.forename: I
authors.initials: I
authors.lastname: Shimada
authors.forename: Y
authors.initials: Y
authors.lastname: Arata
mesh_terms: D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000737:chemistry; D000941:Antigens / Q000276:immunology / Q000378:metabolism; D001666:Binding Sites, Antibody; D003546:Cysteine Endopeptidases / Q000378:metabolism; D003619:Dansyl Compounds; D007128:Immunoglobulin Fragments; D007074:Immunoglobulin G / Q000737:chemistry; D007136:Immunoglobulins / Q000737:chemistry* / Q000378:metabolism; D008239:Lysine / Q000031:analogs & derivatives / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry; D011994:Recombinant Proteins / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000911:Antibodies, Monoclonal; D000941:Antigens; D003619:Dansyl Compounds; D007128:Immunoglobulin Fragments; D007074:Immunoglobulin G; D007136:Immunoglobulins; D010446:Peptide Fragments; D011994:Recombinant Proteins; C055966:immunoglobulin Fv; C036851:dansyllysine; D003546:Cysteine Endopeptidases; C019913:clostripain; D008239:Lysine