1KUX

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


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.225 
  • R-Value Work: 0.197 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

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

  • DOI: 10.1006/jmbi.2001.5371
  • Primary Citation of Related Structures:  1KUV, 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 diffra ...

    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.


    Organizational Affiliation

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




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Serotonin N-acetyltransferase
A
207Ovis ariesGene Names: AANAT (SNAT)
EC: 2.3.1.87
Find proteins for Q29495 (Ovis aries)
Go to Gene View: AANAT
Go to UniProtKB:  Q29495
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CA3
Query on CA3

Download SDF File 
Download CCD File 
A
COA-S-TRIMETHYLENE-ACETYL-TRYPTAMINE
C36 H54 N9 O17 P3 S
RFOXOYXMKJPZDH-VTINEICCSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
CA3Ki: 340 nM BINDINGMOAD
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.225 
  • R-Value Work: 0.197 
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 53.455α = 90.00
b = 68.567β = 90.00
c = 89.791γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
SCALEPACKdata scaling
DENZOdata reduction
AMoREphasing
ADSCdata collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-03-22
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance