1YRL

Escherichia coli ketol-acid reductoisomerase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.223 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

The crystal structure of a bacterial class II ketol-acid reductoisomerase: domain conservation and evolution

Tyagi, R.Duquerroy, S.Navaza, J.Guddat, L.W.Duggleby, R.G.

(2005) Protein Sci. 14: 3089-3100

  • DOI: 10.1110/ps.051791305

  • PubMed Abstract: 
  • Ketol-acid reductoisomerase (KARI; EC 1.1.1.86) catalyzes two steps in the biosynthesis of branched-chain amino acids. Amino acid sequence comparisons across species reveal that there are two types of this enzyme: a short form (Class I) found in fung ...

    Ketol-acid reductoisomerase (KARI; EC 1.1.1.86) catalyzes two steps in the biosynthesis of branched-chain amino acids. Amino acid sequence comparisons across species reveal that there are two types of this enzyme: a short form (Class I) found in fungi and most bacteria, and a long form (Class II) typical of plants. Crystal structures of each have been reported previously. However, some bacteria such as Escherichia coli possess a long form, where the amino acid sequence differs appreciably from that found in plants. Here, we report the crystal structure of the E. coli enzyme at 2.6 A resolution, the first three-dimensional structure of any bacterial Class II KARI. The enzyme consists of two domains, one with mixed alpha/beta structure, which is similar to that found in other pyridine nucleotide-dependent dehydrogenases. The second domain is mainly alpha-helical and shows strong evidence of internal duplication. Comparison of the active sites between KARI of E. coli, Pseudomonas aeruginosa, and spinach shows that most residues occupy conserved positions in the active site. E. coli KARI was crystallized as a tetramer, the likely biologically active unit. This contrasts with P. aeruginosa KARI, which forms a dodecamer, and spinach KARI, a dimer. In the E. coli KARI tetramer, a novel subunit-to-subunit interacting surface is formed by a symmetrical pair of bulbous protrusions.


    Organizational Affiliation

    School of Molecular and Microbial Sciences, The University of Queensland, Brisbane, QLD 4072, Australia.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Ketol-acid reductoisomerase
A, B, C, D
491Escherichia coli (strain K12)Gene Names: ilvC
EC: 1.1.1.86
Find proteins for P05793 (Escherichia coli (strain K12))
Go to UniProtKB:  P05793
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A, B, C, D
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.223 
  • Space Group: P 63
Unit Cell:
Length (Å)Angle (°)
a = 226.882α = 90.00
b = 226.882β = 90.00
c = 118.853γ = 120.00
Software Package:
Software NamePurpose
CNSrefinement
CrystalCleardata reduction
CrystalCleardata scaling
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-10-11
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-10-11
    Type: Refinement description