2ACE | pdb_00002ace

NATIVE ACETYLCHOLINESTERASE (E.C. 3.1.1.7) FROM TORPEDO CALIFORNICA

• PDB DOI: https://doi.org/10.2210/pdb2ACE/pdb
• Entry: 2ACE supersedes: 1ACE

• Classification: SERINE HYDROLASE
• Organism(s): Tetronarce californica
• Mutation(s): No 


• Deposited: 1996-06-23 Released: 1996-11-08 
• Deposition Author(s): Harel, M., Raves, M.L., Silman, I., Sussman, J.L.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 
  0.258 (Depositor), 0.231 (DCC) 
• R-Value Work: 
  0.199 (Depositor), 0.181 (DCC) 
• R-Value Observed: 
  0.199 (Depositor) 

Starting Model: experimental

Literature

Structure of acetylcholinesterase complexed with the nootropic alkaloid, (-)-huperzine A.

Raves, M.L., Harel, M., Pang, Y.-P., Silman, I., Kozikowski, A.P., Sussman, J.L.

(1997) Nat Struct Biol 4: 57-63

• PubMed: 8989325 
• DOI: https://doi.org/10.1038/nsb0197-57
• Primary Citation Related Structures: 
  1VOT, 2ACE


• PubMed Abstract: 
  

  (-)-Huperzine A (HupA) is found in an extract from a club moss that has been used for centuries in Chinese folk medicine. Its action has been attributed to its ability to strongly inhibit acetylcholinesterase (AChE). The crystal structure of the complex of AChE with optically pure HupA at 2.5 A resolution shows an unexpected orientation for the inhibitor with surprisingly few strong direct interactions with protein residues to explain its high affinity. This structure is compared to the native structure of AChE devoid of any inhibitor as determined to the same resolution. An analysis of the affinities of structural analogues of HupA, correlated with their interactions with the protein, shows the importance of individual hydrophobic interactions between HupA and aromatic residues in the active-site gorge of AChE.

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Organizational Affiliation: 
• Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content 

• Total Structure Weight: 60.88 kDa 
• Atom Count: 4,357 
• Modeled Residue Count: 527 
• Deposited Residue Count: 537 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
ACETYLCHOLINESTERASE	A	537	Tetronarce californica	Mutation(s): 0  EC: 3.1.1.7
UniProt
Find proteins for P04058 (Tetronarce californica) Explore P04058  Go to UniProtKB:  P04058

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ACH	B [auth A]	ACETYLCHOLINE C7 H16 N O2 OIPILFWXSMYKGL-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free:  0.258 (Depositor), 0.231 (DCC) 
• R-Value Work:  0.199 (Depositor), 0.181 (DCC) 
• R-Value Observed: 0.199 (Depositor) 

Space Group: P 3₁ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 112.41	α = 90
b = 112.41	β = 90
c = 136.7	γ = 120

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
X-PLOR	model building
X-PLOR	refinement
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1996-11-08 
Deposition Author(s): Harel, M., Raves, M.L., Silman, I., Sussman, J.L.
• This entry supersedes: 1ACE

Revision History  

• Version 1.0: 1996-11-08
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2016-06-22
  Changes: Derived calculations
• Version 1.4: 2023-08-09
  Changes: Data collection, Database references, Derived calculations, Refinement description
• Version 1.5: 2024-10-23
  Changes: Data collection, Structure summary