3IXV

Scorpion Hemocyanin resting state pseudo atomic model built based on cryo-EM density map

3IXV の概要

• エントリーDOI: 10.2210/pdb3ixv/pdb
• 関連するPDBエントリー: 3IXW
• EMDBエントリー: 5100 5101
• 分子名称: Hemocyanin AA6 chain (1 entity in total)
• 機能のキーワード: hemocyanin, hc, phenolxoidase activity, tyrosinase (ty), catecholoxidase (co), enzyme, sds, cryo-em, single particle analysis, copper, metal-binding, oxygen transport, phosphoprotein, secreted, transport, oxygen binding
• 由来する生物種: Androctonus australis (Sahara scorpion)
• タンパク質・核酸の鎖数: 12
• 化学式量合計: 862604.34

構造登録者

Cong, Y.,Zhang, Q.,Woolford, D.,Schweikardt, T.,Khant, H.,Ludtke, S.,Chiu, W.,Decker, H. (登録日: 2009-02-13, 公開日: 2009-06-02, 最終更新日: 2024-02-21)

主引用文献

Cong, Y.,Zhang, Q.,Woolford, D.,Schweikardt, T.,Khant, H.,Dougherty, M.,Ludtke, S.J.,Chiu, W.,Decker, H.
Structural Mechanism of SDS-Induced Enzyme Activity of Scorpion Hemocyanin Revealed by Electron Cryomicroscopy.
Structure, 17:749-758, 2009

PubMed Abstract: Phenoloxidases (POs) occur in all organisms and are involved in skin and hair coloring in mammals, and initiating melanization in wound healing. Mutation or overexpression of PO can cause albinism or melanoma, respectively. SDS can convert inactive PO and the oxygen carrier hemocyanin (Hc) into enzymatically active PO. Here we present single-particle cryo-EM maps at subnanometer resolution and pseudoatomic models of the 24-oligomeric Hc from scorpion Pandinus imperator in resting and SDS-activated states. Our structural analyses led to a plausible mechanism of Hc enzyme PO activation: upon SDS activation, the intrinsically flexible Hc domain I twists away from domains II and III in each subunit, exposing the entrance to the active site; this movement is stabilized by enhanced interhexamer and interdodecamer interactions, particularly in the central linker subunits. This mechanism could be applicable to other type 3 copper proteins, as the active site is highly conserved.

PubMed: 19446530
DOI: 10.1016/j.str.2009.03.005

実験手法

ELECTRON MICROSCOPY (6.8 Å)