1JOT

STRUCTURE OF THE LECTIN MPA COMPLEXED WITH T-ANTIGEN DISACCHARIDE

1JOT の概要

• エントリーDOI: 10.2210/pdb1jot/pdb
• 関連するBIRD辞書のPRD_ID: PRD_900084
• 分子名称: AGGLUTININ, beta-D-galactopyranose-(1-3)-2-acetamido-2-deoxy-alpha-D-galactopyranose, ... (4 entities in total)
• 機能のキーワード: multi-wavelength anomalous diffraction (mad), t-antigen, lectin, maclura pomifera, beta prism
• 由来する生物種: Maclura pomifera (Osage orange); 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 17296.32

構造登録者

Lee, X.,Thompson, A.,Zhang, Z.,Hoa, T.-T.,Biesterfeldt, J.,Ogata, C.,Xu, L.,Johnston, R.A.Z.,Young, N.M. (登録日: 1997-12-05, 公開日: 1998-12-30, 最終更新日: 2024-04-03)

主引用文献

Lee, X.,Thompson, A.,Zhang, Z.,Ton-that, H.,Biesterfeldt, J.,Ogata, C.,Xu, L.,Johnston, R.A.,Young, N.M.
Structure of the complex of Maclura pomifera agglutinin and the T-antigen disaccharide, Galbeta1,3GalNAc.
J.Biol.Chem., 273:6312-6318, 1998

PubMed Abstract: Maclura pomifera agglutinin is a tetrameric plant seed lectin with high affinity for the tumor-associated T-antigen disaccharide, Galbeta1,3GalNAcalpha, and hence for many O-linked glycopeptide structures. Unlike members of most lectin families, it lacks both metal ions and Cys residues. The structure of its complex with Galbeta1,3GalNAc was determined to 2.2 by first using multiwavelength anomalous diffraction with a lead derivative of the native protein, and then using molecular replacement with the unrefined structure as a model to solve the structure of the complex. The subunits share the beta-prism architecture and three-fold pseudo-symmetry of the related lectin jacalin, with the 21-residue beta-chains in the center of the tetramer. Interactions with the GalNAc predominate in the binding of the disaccharide. It forms a network of H-bonds with only one side chain, from an Asp residue, the amino group of the N-terminal Gly of the alpha-chain, and peptide backbone atoms of two aromatic residues. The Gal moiety does not H-bond directly with residues in the same monomer, i.e. there is no true subsite for it, but there are interactions through two water molecules. In the crystal, it interacts with residues in the binding site of an adjacent tetramer. The minimum energy conformation expected for the disaccharide is retained, despite its mediating the tetramer-tetramer interactions in the crystal packing. The resulting lattice is comparable to those seen for complexes of other lectins with branched glycopeptides.

PubMed: 9497359
DOI: 10.1074/jbc.273.11.6312

実験手法

X-RAY DIFFRACTION (2.2 Å)