6CTS

PROPOSED MECHANISM FOR THE CONDENSATION REACTION OF CITRATE SYNTHASE. 1.9-ANGSTROMS STRUCTURE OF THE TERNARY COMPLEX WITH OXALOACETATE AND CARBOXYMETHYL COENZYME A


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Observed: 0.110 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Proposed mechanism for the condensation reaction of citrate synthase: 1.9-A structure of the ternary complex with oxaloacetate and carboxymethyl coenzyme A.

Karpusas, M.Branchaud, B.Remington, S.J.

(1990) Biochemistry 29: 2213-2219

  • Primary Citation of Related Structures:  
    6CTS, 5CTS

  • PubMed Abstract: 
  • The crystal structure of the ternary complex citrate synthase-oxaloacetate-carboxymethyl coenzyme A has been solved to a resolution of 1.9 A and refined to a conventional crystallographic R factor of 0.185. The structure resembles a proposed transition state of the condensation reaction and suggests that the condensation reaction proceeds through a neutral enol rather than an enolate intermediate ...

    The crystal structure of the ternary complex citrate synthase-oxaloacetate-carboxymethyl coenzyme A has been solved to a resolution of 1.9 A and refined to a conventional crystallographic R factor of 0.185. The structure resembles a proposed transition state of the condensation reaction and suggests that the condensation reaction proceeds through a neutral enol rather than an enolate intermediate. A mechanism for the condensation reaction is proposed which involves the participation of three key catalytic groups (Asp 375, His 274, and His 320) in two distinct steps. The proposed mechanism invokes concerted general acid-base catalysis twice to explain both the energetics of the reaction and the experimentally observed inversion of stereochemistry at the attacking carbon atom.


    Related Citations: 
    • Crystal Structure Analysis and Molecular Model of a Complex of Citrate Synthase with Oxaloacetate and S-Acetonyl-Coenzymea
      Wiegand, G., Remington, S., Deisenhofer, J., Huber, R.
      (1984) J Mol Biol 174: 205
    • Crystallographic Refinement and Atomic Models of Two Different Forms of Citrate Synthase at 2.7 And 1.7 Angstroms Resolution
      Remington, S., Wiegand, G., Huber, R.
      (1982) J Mol Biol 158: 111
    • Primary Structure of Porcine Heart Citrate Synthase
      Bloxham, D.P., Parmelee, D.C., Kumar, S., Wade, R.D., Ericsson, L.H., Neurath, H., Walsh, K.A., Titani, K.
      (1981) Proc Natl Acad Sci U S A 78: 5381
    • Crystal Structure Analysis of the Tetragonal Crystal Form and Preliminary Molecular Model of Pig-Heart Citrate Synthase
      Wiegand, G., Kukla, D., Scholze, H., Jones, T.A., Huber, R.
      (1979) Eur J Biochem 93: 41

    Organizational Affiliation

    Institute of Molecular Biology, University of Oregon, Eugene 97403.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
CITRATE SYNTHASEA433Gallus gallusMutation(s): 0 
Gene Names: CS
EC: 4.1.3.7 (PDB Primary Data), 2.3.3.1 (UniProt)
UniProt
Find proteins for P23007 (Gallus gallus)
Explore P23007 
Go to UniProtKB:  P23007
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CIC (Subject of Investigation/LOI)
Query on CIC

Download Ideal Coordinates CCD File 
B [auth A]CITRYL-THIOETHER-COENZYME *A
C27 H44 N7 O21 P3 S
VPFUWJMPUQBRCJ-QVYRMQCDSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Observed: 0.110 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 104α = 90
b = 78.1β = 78.9
c = 58.3γ = 90
Software Package:
Software NamePurpose
TNTrefinement

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1990-10-15
    Type: Initial release
  • Version 1.1: 2008-03-25
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Version format compliance
  • Version 1.3: 2017-11-29
    Changes: Derived calculations, Other