2ZG2

Crystal Structure of Two N-terminal Domains of Native Siglec-5

2ZG2 の概要

• エントリーDOI: 10.2210/pdb2zg2/pdb
• 関連するPDBエントリー: 1NKO 1O7S 1QFO 2DF3 2G5R 2HRL 2ZG1 2ZG3
• 分子名称: Sialic acid-binding Ig-like lectin 5 (2 entities in total)
• 機能のキーワード: siglec-5 inhibitory receptor, two-domain structure, v-set, c2-set, ig-like domain, sialic acid, cell adhesion, glycoprotein, immunoglobulin domain, lectin, membrane, polymorphism, transmembrane, immune system-carbohydrate binding protein complex, immune system/carbohydrate binding protein
• 由来する生物種: Homo sapiens (human)
• 細胞内の位置: Membrane; Single-pass type I membrane protein: O15389
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 24532.59

構造登録者

Zhuravleva, M.A.,Sun, P.D. (登録日: 2008-01-17, 公開日: 2008-02-05, 最終更新日: 2024-10-16)

主引用文献

Zhuravleva, M.A.,Trandem, K.,Sun, P.D.
Structural implications of Siglec-5-mediated sialoglycan recognition
J.Mol.Biol., 375:437-447, 2008

PubMed Abstract: Sialic acid (Sia) Ig-like binding lectins are important mediators of recognition and signaling events among myeloid cells. To investigate the molecular mechanism underlying sialic acid Ig-like lectin (Siglec) functions, we determined the crystal structure of the two N-terminal extracellular domains of human myeloid cell inhibitory receptor Siglec-5 (CD170) and its complexes with two sialylated carbohydrates. The native structure revealed an unusual conformation of the CC' ligand specificity loop and a unique interdomain disulfide bond. The alpha(2,3)- and alpha(2,6)-sialyllactose complexed structures showed a conserved Sia recognition motif that involves both Arg124 and a portion of the G-strand in the V-set domain forming beta-sheet-like hydrogen bonds with the glycerol side chain of the Sia. Only few protein contacts to the subterminal sugars are observed and mediated by the highly variable GG' linker and CC' loop. These structural observations, in conjunction with surface plasmon resonance binding assays, provide mechanistic insights into linkage-dependent Siglec carbohydrate recognition and suggest that Siglec-5 and other CD33-related Siglec receptors are more promiscuous in sialoglycan recognition than previously understood.

PubMed: 18022638
DOI: 10.1016/j.jmb.2007.10.009

実験手法

X-RAY DIFFRACTION (2.85 Å)