3BLE

Crystal structure of the catalytic domain of LiCMS in complexed with malonate


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.223 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Molecular basis of the substrate specificity and the catalytic mechanism of citramalate synthase from Leptospira interrogans

Ma, J.Zhang, P.Zhang, Z.Zha, M.Xu, H.Zhao, G.Ding, J.

(2008) Biochem.J. 415: 45-56

  • DOI: 10.1042/BJ20080242
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Leptospira interrogans is the causative agent for leptospirosis, a zoonotic disease of global importance. In contrast with most other micro-organisms, L. interrogans employs a pyruvate pathway to synthesize isoleucine and LiCMS (L. interrogans citram ...

    Leptospira interrogans is the causative agent for leptospirosis, a zoonotic disease of global importance. In contrast with most other micro-organisms, L. interrogans employs a pyruvate pathway to synthesize isoleucine and LiCMS (L. interrogans citramalate synthase) catalyses the first reaction of the pathway which converts pyruvate and acetyl-CoA into citramalate, thus making it an attractive target for the development of antibacterial agents. We report here the crystal structures of the catalytic domain of LiCMS and its complexes with substrates, and kinetic and mutagenesis studies of LiCMS, which together reveal the molecular basis of the high substrate specificity and the catalytic mechanism of LiCMS. The catalytic domain consists of a TIM barrel flanked by an extended C-terminal region. It forms a homodimer in the crystal structure, and the active site is located at the centre of the TIM barrel near the C-terminal ends of the beta-strands and is composed of conserved residues of the beta-strands of one subunit and the C-terminal region of the other. The substrate specificity of LiCMS towards pyruvate against other alpha-oxo acids is dictated primarily by residues Leu(81), Leu(104) and Tyr(144), which form a hydrophobic pocket to accommodate the C(2)-methyl group of pyruvate. The catalysis follows the typical aldol condensation reaction, in which Glu(146) functions as a catalytic base to activate the methyl group of acetyl-CoA to form an enolated acetyl-CoA intermediate and Arg(16) as a general acid to stabilize the intermediate.


    Organizational Affiliation

    Laboratory of Microbial Molecular Physiology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Feng-Lin Road, Shanghai 200032, China.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Citramalate synthase from Leptospira interrogans
A
337Leptospira interrogans serogroup Icterohaemorrhagiae serovar Lai (strain 56601)Mutation(s): 0 
Gene Names: leuA
Find proteins for Q8F3Q1 (Leptospira interrogans serogroup Icterohaemorrhagiae serovar Lai (strain 56601))
Go to UniProtKB:  Q8F3Q1
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
A
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
MLI
Query on MLI

Download SDF File 
Download CCD File 
A
MALONATE ION
C3 H2 O4
OFOBLEOULBTSOW-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.223 
  • Space Group: P 31 2 1
Unit Cell:
Length (Å)Angle (°)
a = 85.158α = 90.00
b = 85.158β = 90.00
c = 112.897γ = 120.00
Software Package:
Software NamePurpose
ADSCdata collection
PDB_EXTRACTdata extraction
SCALEPACKdata scaling
CNSrefinement
HKL-2000data reduction
HKL-2000data scaling
SOLVEphasing
RESOLVEphasing
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2007-12-11 
  • Released Date: 2008-11-11 
  • Deposition Author(s): Zhang, P., Ma, J.

Revision History 

  • Version 1.0: 2008-11-11
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2017-10-25
    Type: Refinement description