22GI

3D1 Fab in complex with pepAVVNQN

22GI の概要

• エントリーDOI: 10.2210/pdb22gi/pdb
• 分子名称: Light chain of 3D1, Heavy chain of 3D1, ALA-VAL-VAL-ASN-GLN-ASN, ... (5 entities in total)
• 機能のキーワード: sads-cov, antibody, spike, hr1, viral protein/immune system, viral protein-immune system complex
• 由来する生物種: Homo sapiens; 詳細
• タンパク質・核酸の鎖数: 12
• 化学式量合計: 184204.31

構造登録者

Lei, Y. (登録日: 2026-01-09, 公開日: 2026-04-15)

主引用文献

Zhang, L.,Liang, Z.,Yang, G.,Yan, L.
Elucidating the Molecular Mechanism of 3D1 Antibody Binding to a Swine Enteric Coronavirus Antigen.
Viruses, 18:-, 2026

PubMed Abstract: The broadly neutralizing monoclonal antibody 3D1 potently neutralizes SADS-CoV by targeting a conserved epitope within the heptad repeat 1 (HR1) domain of the viral spike protein. Structural and biophysical analyses demonstrate that 3D1 binds with high affinity to a specific linear β-turn motif (residues A804-N809) in HR1. High-resolution crystallography reveals that this motif sits within a deep, electrostatically complementary paratope groove. Critically, 3D1 binding competitively inhibits the essential interaction between HR1 and HR2. Notably, its recognition is not dependent on HR1's native helical conformation, as it maintains strong binding to conformationally constrained, stapled helical peptides. Collectively, the data indicate that 3D1 neutralizes by capturing a pre-hairpin intermediate state of HR1-a transition state between prefusion and postfusion forms-thereby sterically blocking the formation of the stable postfusion six-helix bundle that is essential for membrane fusion. This work defines a precise, structure-dependent neutralizing epitope and elucidates a mechanism of action that involves trapping a key fusion intermediate, offering a valuable template for the design of broad-spectrum coronavirus therapeutics.

PubMed: 41754551
DOI: 10.3390/v18020208

実験手法

X-RAY DIFFRACTION (2.64 Å)