1ETZ

THE THREE-DIMENSIONAL STRUCTURE OF AN ANTI-SWEETENER FAB, NC10.14, SHOWS THE EXTENT OF STRUCTURAL DIVERSITY IN ANTIGEN RECOGNITION BY IMMUNOGLOBULINS

1ETZ の概要

• エントリーDOI: 10.2210/pdb1etz/pdb
• 関連するPDBエントリー: 1CGS 2CGR
• 分子名称: FAB NC10.14 - LIGHT CHAIN, FAB NC10.14 - HEAVY CHAIN, N-(P-CYANOPHENYL)-N'-DIPHENYLMETHYL-GUANIDINE-ACETIC ACID, ... (4 entities in total)
• 機能のキーワード: anti-sweetener fab, antigen-antibody, complex, receptor mimicry, antigen recognition, immune system
• 由来する生物種: Mus musculus (house mouse); 詳細
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 96036.59

構造登録者

Guddat, L.W.,Shan, L.,Broomell, C.,Ramsland, P.A.,Fan, Z.,Anchin, J.M.,Linthicum, D.S.,Edmundson, A.B. (登録日: 2000-04-13, 公開日: 2000-10-18, 最終更新日: 2024-11-13)

主引用文献

Guddat, L.W.,Shan, L.,Broomell, C.,Ramsland, P.A.,Fan, Z.,Anchin, J.M.,Linthicum, D.S.,Edmundson, A.B.
The three-dimensional structure of a complex of a murine Fab (NC10. 14) with a potent sweetener (NC174): an illustration of structural diversity in antigen recognition by immunoglobulins.
J.Mol.Biol., 302:853-872, 2000

PubMed Abstract: The three-dimensional structure of a complex of an Fab from a murine IgG2b(lambda) antibody (NC10.14) with a high potency sweet tasting hap- ten, N-(p-cyanophenyl)-N'-(diphenylmethyl)-N"-(carboxymethyl)guan idine (NC174), has been determined to 2.6 A resolution by X-ray crystallography. This complex crystallized in the triclinic space group P1, with two molecules in the asymmetric unit. In contrast to a companion monoclonal antibody (NC6.8) with a kappa-type light chain and similar high affinity for the NC174 ligand, the NC10.14 antibody possessed a large and deep antigen combining site bounded primarily by the third complementarity-determining regions (CDR3s) of the light and heavy chains. CDR3 of the heavy chain dominated the site and its crown protruded into the external solvent as a type 1' beta-turn. NC174 was nested against HCDR3 and was held in place by two tryptophan side-chains (L91 and L96) from LCDR3. The diphenyl rings were accommodated on an upper tier of the binding pocket that is largely hydrophobic. At the floor of the site, a positively charged arginine side-chain (H95) stabilized the orientation of the electronegative cyano group of the hapten. The negative charge on the acetate group was partially neutralized by a hydrogen bond with the phenolic hydroxyl group of tyrosine H58. Comparisons of the modes of binding of NC174 to the NC6.8 and NC10.14 antibodies illustrate the enormous structural and mechanistic diversity manifest by immune responses.

PubMed: 10993728
DOI: 10.1006/jmbi.2000.4083

実験手法

X-RAY DIFFRACTION (2.6 Å)