1T7O

Crystal structure of the M564G mutant of murine carnitine acetyltransferase in complex with carnitine


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.262 
  • R-Value Work: 0.203 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural and biochemical studies of the substrate selectivity of carnitine acetyltransferase

Hsiao, Y.-S.Jogl, G.Tong, L.

(2004) J.Biol.Chem. 279: 31584-31589

  • DOI: 10.1074/jbc.M403484200
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Carnitine acyltransferases catalyze the exchange of acyl groups between coenzyme A (CoA) and carnitine. They have important roles in many cellular processes, especially the oxidation of long-chain fatty acids, and are attractive targets for drug disc ...

    Carnitine acyltransferases catalyze the exchange of acyl groups between coenzyme A (CoA) and carnitine. They have important roles in many cellular processes, especially the oxidation of long-chain fatty acids, and are attractive targets for drug discovery against diabetes and obesity. These enzymes are classified based on their substrate selectivity for short-chain, medium-chain, or long-chain fatty acids. Structural information on carnitine acetyltransferase suggests that residues Met-564 and Phe-565 may be important determinants of substrate selectivity with the side chain of Met-564 located in the putative binding pocket for acyl groups. Both residues are replaced by glycine in carnitine palmitoyltransferases. To assess the functional relevance of this structural observation, we have replaced these two residues with small amino acids by mutagenesis, characterized the substrate preference of the mutants, and determined the crystal structures of two of these mutants. Kinetic studies confirm that the M564G or M564A mutation is sufficient to increase the activity of the enzyme toward medium-chain substrates with hexanoyl-CoA being the preferred substrate for the M564G mutant. The crystal structures of the M564G mutant, both alone and in complex with carnitine, reveal a deep binding pocket that can accommodate the larger acyl group. We have determined the crystal structure of the F565A mutant in a ternary complex with both the carnitine and CoA substrates at a 1.8-A resolution. The F565A mutation has minor effects on the structure or the substrate preference of the enzyme.


    Organizational Affiliation

    Department of Biological Sciences, Columbia University, New York, New York 10027, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Carnitine acetyltransferase
A
618Mus musculusMutation(s): 1 
Gene Names: Crat
EC: 2.3.1.7
Find proteins for P47934 (Mus musculus)
Go to UniProtKB:  P47934
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
152
Query on 152

Download SDF File 
Download CCD File 
A
CARNITINE
(3-CARBOXY-2-(R)-HYDROXY-PROPYL)-TRIMETHYL-AMMONIUM
C7 H16 N O3
PHIQHXFUZVPYII-ZCFIWIBFSA-O
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.262 
  • R-Value Work: 0.203 
  • Space Group: P 43
Unit Cell:
Length (Å)Angle (°)
a = 71.340α = 90.00
b = 71.340β = 90.00
c = 128.770γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
CNSphasing
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-06-22
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance