Structures of ligand bound human choline acetyltransferase provides insight into regulation of acetylcholine synthesis

Experimental Data Snapshot

  • Resolution: 2.27 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.196 
  • R-Value Observed: 0.211 

wwPDB Validation   3D Report Full Report

This is version 1.5 of the entry. See complete history


Substrate binding and catalytic mechanism of human choline acetyltransferase.

Kim, A.R.Rylett, R.J.Shilton, B.H.

(2006) Biochemistry 45: 14621-14631

  • DOI: https://doi.org/10.1021/bi061536l
  • Primary Citation of Related Structures:  
    2FY2, 2FY3, 2FY4, 2FY5

  • PubMed Abstract: 

    Choline acetyltransferase (ChAT) catalyzes the synthesis of the neurotransmitter acetylcholine from choline and acetyl-CoA, and its presence is a defining feature of cholinergic neurons. We report the structure of human ChAT to a resolution of 2.2 A along with structures for binary complexes of ChAT with choline, CoA, and a nonhydrolyzable acetyl-CoA analogue, S-(2-oxopropyl)-CoA. The ChAT-choline complex shows which features of choline are important for binding and explains how modifications of the choline trimethylammonium group can be tolerated by the enzyme. A detailed model of the ternary Michaelis complex fully supports the direct transfer of the acetyl group from acetyl-CoA to choline through a mechanism similar to that seen in the serine hydrolases for the formation of an acyl-enzyme intermediate. Domain movements accompany CoA binding, and a surface loop, which is disordered in the unliganded enzyme, becomes localized and binds directly to the phosphates of CoA, stabilizing the complex. Interactions between this surface loop and CoA may function to lower the KM for CoA and could be important for phosphorylation-dependent regulation of ChAT activity.

  • Organizational Affiliation

    Department of Biochemistry, and Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, Ontario, Canada.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Choline O-acetyltransferase612Homo sapiensMutation(s): 7 
Gene Names: CHAT
UniProt & NIH Common Fund Data Resources
Find proteins for P28329 (Homo sapiens)
Explore P28329 
Go to UniProtKB:  P28329
PHAROS:  P28329
GTEx:  ENSG00000070748 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP28329
Sequence Annotations
  • Reference Sequence
Small Molecules
Binding Affinity Annotations 
IDSourceBinding Affinity
CHT BindingDB:  2FY3 Ki: min: 4.00e+5, max: 7.60e+6 (nM) from 2 assay(s)
Experimental Data & Validation

Experimental Data

  • Resolution: 2.27 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.196 
  • R-Value Observed: 0.211 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 54.78α = 90
b = 76.26β = 90
c = 164.29γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
PDB_EXTRACTdata extraction
MAR345data collection

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2006-12-12
    Type: Initial release
  • Version 1.1: 2008-05-01
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Non-polymer description, Version format compliance
  • Version 1.3: 2017-10-18
    Changes: Refinement description
  • Version 1.4: 2021-10-20
    Changes: Database references, Derived calculations
  • Version 1.5: 2023-08-30
    Changes: Data collection, Refinement description