Biological Assembly 1  

 3D View: Structure | 1D-3D View | Validation Report | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 24.08 kDa 
• Atom Count: 1512 
• Modelled Residue Count: 166 
• Deposited Residue Count: 207 
• Unique protein chains: 1

1KUY

X-ray Crystallographic Studies of Serotonin N-acetyltransferase Catalysis and Inhibition

• PDB DOI: 10.2210/pdb1KUY/pdb

• Classification: TRANSFERASE
• Organism(s): Ovis aries
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2002-01-22 Released: 2002-03-22 
• Deposition Author(s): Wolf, E., De Angelis, J., Khalil, E.M., Cole, P.A., Burley, S.K.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Free: 0.276 
• R-Value Work: 0.203 
• R-Value Observed: 0.211 

Literature

X-ray crystallographic studies of serotonin N-acetyltransferase catalysis and inhibition.

Wolf, E., De Angelis, J., Khalil, E.M., Cole, P.A., Burley, S.K.

(2002) J Mol Biol 317: 215-224

• PubMed: 11902838 
• DOI: 10.1006/jmbi.2001.5371
• Primary Citation of Related Structures:  
  1KUV, 1KUX, 1KUY


• PubMed Abstract: 
  

The structure of serotonin N-acetyltransferase (also known as arylalkylamine N-acetyltransferase; AANAT) bound to a potent bisubstrate analog inhibitor has been determined at 2.0 A resolution using a two-edge (Se, Br) multiwavelength anomalous diffraction (MAD) experiment. This acetyl-CoA dependent enzyme is a member of the GCN5-related family of N-acetyltransferases (GNATs), which share four conserved sequence motifs (A-D). In serotonin N-acetyltransferase, motif A adopts an alpha/beta conformation characteristic of the phylogenetically invariant cofactor binding site seen in all previously characterized GNATs. Motif B displays a significantly lower level of conservation among family members, giving rise to a novel alpha/beta structure for the serotonin binding slot. Utilization of a brominated CoA-S-acetyl-tryptamine-bisubstrate analog inhibitor and the MAD method permitted conclusive identification of two radically different conformations for the tryptamine moiety in the catalytic site (cis and trans). A second high-resolution X-ray structure of the enzyme bound to a bisubstrate analog inhibitor, with a longer tether between the acetyl-CoA and tryptamine moieties, demonstrates only the trans conformation. Given a previous proposal that AANAT can catalyze an alkyltransferase reaction in a conformationally altered active site relative to its acetyltransferase activity, it is possible that the two conformations of the bisubstrate analog observed crystallographically correspond to these alternative reaction pathways. Our findings may ultimately lead to the design of analogs with improved AANAT inhibitory properties for in vivo applications.

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Organizational Affiliation: 

Laboratories of Molecular Biophysics, The Rockefeller University, New York, NY 10021, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Serotonin N-acetyltransferase	A	207	Ovis aries	Mutation(s): 0  Gene Names: U29663, AANAT, SNAT EC: 2.3.1.87
UniProt
Find proteins for Q29495 (Ovis aries) Explore Q29495  Go to UniProtKB:  Q29495

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
COT	B [auth A]	COA-S-ACETYL TRYPTAMINE C33 H48 N9 O17 P3 S ZRDQFWRSRPZOSQ-GMHMEAMDSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
COT	Binding MOAD:  1KUY	Ki: 48 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Free: 0.276 
• R-Value Work: 0.203 
• R-Value Observed: 0.211 
• Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 53.152	α = 90
b = 68.79	β = 90
c = 89.651	γ = 90

Software Package:

Software Name	Purpose
AMoRE	phasing
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2002-01-22 
• Released Date: 2002-03-22 
Deposition Author(s): Wolf, E., De Angelis, J., Khalil, E.M., Cole, P.A., Burley, S.K.

Revision History  

• Version 1.0: 2002-03-22
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2017-10-11
  Changes: Refinement description
• Version 1.4: 2021-02-03
  Changes: Database references, Derived calculations, Structure summary