2J4F

Torpedo acetylcholinesterase - Hg heavy-atom derivative

2J4F の概要

• エントリーDOI: 10.2210/pdb2j4f/pdb
• 関連するPDBエントリー: 1ACJ 1ACL 1AMN 1AX9 1CFJ 1DX6 1E3Q 1E66 1EA5 1EEA 1EVE 1FSS 1GPK 1GPN 1GQR 1GQS 1H22 1H23 1HBJ 1JGA 1JGB 1JJB 1OCE 1ODC 1QID 1QIE 1QIF 1QIG 1QIH 1QII 1QIJ 1QIK 1QIM 1QTI 1SOM 1U65 1UT6 1VOT 1VXO 1VXR 1W4L 1W6R 1W75 1W76 1ZGB 1ZGC 2ACE 2ACK 2C4H 2C58 2C5F 2C5G 2CEK 2CKM 2CMF 2DFP 2J3D 2J3Q 3ACE 4ACE
• 分子名称: ACETYLCHOLINESTERASE, MERCURY (II) ION (3 entities in total)
• 機能のキーワード: hydrolase, neurotransmitter degradation, neurotransmitter cleavage, alternative splicing, alpha-beta hydrolase, serine esterase, serine hydrolase, catalytic triad, lipoprotein, glycoprotein, cholinesterase, synapse, membrane, gpi-anchor
• 由来する生物種: TORPEDO CALIFORNICA (PACIFIC ELECTRIC RAY)
• 細胞内の位置: Isoform H: Cell membrane; Lipid-anchor, GPI- anchor. Isoform T: Cell membrane; Peripheral membrane protein: P04058
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 61726.27

構造登録者

Kreimer, D.I.,Dolginova, E.A.,Raves, M.,Sussman, J.L.,Silman, I.,Weiner, L. (登録日: 2006-08-30, 公開日: 2006-09-05, 最終更新日: 2024-10-09)

主引用文献

Kreimer, D.I.,Dolginova, E.A.,Raves, M.,Sussman, J.L.,Silman, I.,Weiner, L.
A Metastable State of Torpedo Californica Acetylcholinesterase Generated by Modification with Organomercurials
Biochemistry, 33:14407-, 1994

PubMed Abstract: Chemical modification of Torpedo californica acetylcholinesterase by various sulfhydryl reagents results in its conversion to one of two principal states. One of these states, viz., that produced by disulfides and alkylating agents, is stable. The second state, produced by mercury derivatives, is metastable. At room temperature, it converts spontaneously, with a half-life of ca. 1 h, to a stable state similar to that produced by the disulfides and alkylating agents. Demodification of acetylcholinesterase freshly modified by mercurials, by its exposure to reduced glutathione, causes rapid release of the bound mercurial, with concomitant recovery of most of the enzymic activity of the native enzyme. In contrast, similar demodification of acetylcholinesterase modified by disulfides yields no detectable recovery of enzymic activity. Spectroscopic measurements, employing CD, intrinsic fluorescence, and binding of 1-anilino-8-naphthalenesulfonate, show that the state produced initially by mercurials is "native-like", whereas that produced by disulfides and alkylating agents, and after prolonged incubation of the mercurial-modified enzyme, is partially unfolded and displays many of the features of the "molten globule" state. Arrhenius plots show that the quasi-native state produced by organomercurials is separated by a low (5 kcal/mol) energy barrier from the native state, whereas the partially unfolded state is separated from the quasi-native state by a high energy barrier (ca. 50 kcal/mol). Comparison of the 3D structures of native acetylcholinesterase and of a heavy-atom derivative obtained with HgAc2 suggests that the mercurial-modified enzyme may be stabilized by additional interactions of the mercury atom attached to the free thiol group of Cys231, specifically with Ser228O gamma with the main-chain nitrogen and carbonyl oxygen of the same serine residue.

PubMed: 7981200
DOI: 10.1021/BI00252A006

実験手法

X-RAY DIFFRACTION (2.8 Å)