6O0E

Saxiphilin:STX complex, soaking

6O0E の概要

• エントリーDOI: 10.2210/pdb6o0e/pdb
• 関連するPDBエントリー: 6O0D
• 分子名称: Saxiphilin, [(3aS,4R,10aS)-2,6-diamino-10,10-dihydroxy-3a,4,9,10-tetrahydro-3H,8H-pyrrolo[1,2-c]purin-4-yl]methyl carbamate (3 entities in total)
• 機能のキーワード: saxitoxin, paralytic shellfish poisoning, antitoxin
• 由来する生物種: Lithobates catesbeiana (American bullfrog)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 189055.18

構造登録者

Yen, T.J.,Lolicato, M.,Minor, D.L. (登録日: 2019-02-16, 公開日: 2019-07-10, 最終更新日: 2019-12-04)

主引用文献

Yen, T.J.,Lolicato, M.,Thomas-Tran, R.,Du Bois, J.,Minor Jr., D.L.
Structure of the saxiphilin:saxitoxin (STX) complex reveals a convergent molecular recognition strategy for paralytic toxins.
Sci Adv, 5:eaax2650-eaax2650, 2019

PubMed Abstract: Dinoflagelates and cyanobacteria produce saxitoxin (STX), a lethal bis-guanidinium neurotoxin causing paralytic shellfish poisoning. A number of metazoans have soluble STX-binding proteins that may prevent STX intoxication. However, their STX molecular recognition mechanisms remain unknown. Here, we present structures of saxiphilin (Sxph), a bullfrog high-affinity STX-binding protein, alone and bound to STX. The structures reveal a novel high-affinity STX-binding site built from a "proto-pocket" on a transferrin scaffold that also bears thyroglobulin domain protease inhibitor repeats. Comparison of Sxph and voltage-gated sodium channel STX-binding sites reveals a convergent toxin recognition strategy comprising a largely rigid binding site where acidic side chains and a cation-π interaction engage STX. These studies reveal molecular rules for STX recognition, outline how a toxin-binding site can be built on a naïve scaffold, and open a path to developing protein sensors for environmental STX monitoring and new biologics for STX intoxication mitigation.

PubMed: 31223657
DOI: 10.1126/sciadv.aax2650

実験手法

X-RAY DIFFRACTION (2.5 Å)