2HA7

Crystal structure of mutant S203A of mouse acetylcholinesterase complexed with butyrylthiocholine

2HA7 の概要

• エントリーDOI: 10.2210/pdb2ha7/pdb
• 関連するPDBエントリー: 1J06 2H9Y 2HA0 2HA2 2HA3 2HA4 2HA5 2HA6
• 分子名称: Acetylcholinesterase, IODIDE ION, 2-(TRIMETHYLAMMONIUM)ETHYL THIOL, ... (7 entities in total)
• 機能のキーワード: hydrolase fold, serine esterase, acetylcholinesterase, mutant, homodimer, glycosylated protein, hydrolase
• 由来する生物種: Mus musculus (house mouse)
• 細胞内の位置: Cell junction, synapse. Isoform H: Cell membrane; Lipid-anchor, GPI- anchor; Extracellular side: P21836
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 121718.78

構造登録者

Bourne, Y.,Radic, Z.,Sulzenbacher, G.,Kim, E.,Taylor, P.,Marchot, P. (登録日: 2006-06-12, 公開日: 2006-07-18, 最終更新日: 2023-10-25)

主引用文献

Bourne, Y.,Radic, Z.,Sulzenbacher, G.,Kim, E.,Taylor, P.,Marchot, P.
Substrate and product trafficking through the active center gorge of acetylcholinesterase analyzed by crystallography and equilibrium binding
J.Biol.Chem., 281:29256-29267, 2006

PubMed Abstract: Hydrolysis of acetylcholine catalyzed by acetylcholinesterase (AChE), one of the most efficient enzymes in nature, occurs at the base of a deep and narrow active center gorge. At the entrance of the gorge, the peripheral anionic site provides a binding locus for allosteric ligands, including substrates. To date, no structural information on substrate entry to the active center from the peripheral site of AChE or its subsequent egress has been reported. Complementary crystal structures of mouse AChE and an inactive mouse AChE mutant with a substituted catalytic serine (S203A), in various complexes with four substrates (acetylcholine, acetylthiocholine, succinyldicholine, and butyrylthiocholine), two non-hydrolyzable substrate analogues (m-(N,N,N-trimethylammonio)-trifluoroacetophenone and 4-ketoamyltrimethylammonium), and one reaction product (choline) were solved in the 2.05-2.65-A resolution range. These structures, supported by binding and inhibition data obtained on the same complexes, reveal the successive positions and orientations of the substrates bound to the peripheral site and proceeding within the gorge toward the active site, the conformations of the presumed transition state for acylation and the acyl-enzyme intermediate, and the positions and orientations of the dissociating and egressing products. Moreover, the structures of the AChE mutant in complexes with acetylthiocholine and succinyldicholine reveal additional substrate binding sites on the enzyme surface, distal to the gorge entry. Hence, we provide a comprehensive set of structural snapshots of the steps leading to the intermediates of catalysis and the potential regulation by substrate binding to various allosteric sites at the enzyme surface.

PubMed: 16837465
DOI: 10.1074/jbc.M603018200

実験手法

X-RAY DIFFRACTION (2.66 Å)