1YRL

Escherichia coli ketol-acid reductoisomerase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.223 
  • R-Value Observed: 0.227 

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
  • Primary Citation of Related Structures:  
    1YRL

  • 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 fungi and most bacteria, and a long form (Class II) typical of plants ...

    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:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Ketol-acid reductoisomeraseA, B, C, D491Escherichia coliMutation(s): 0 
Gene Names: ilvC
EC: 1.1.1.86
Find proteins for P05793 (Escherichia coli (strain K12))
Explore P05793 
Go to UniProtKB:  P05793
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download Ideal Coordinates CCD File 
E [auth A] , F [auth A] , G [auth A] , H [auth A] , I [auth B] , J [auth C] , K [auth D] , L [auth D] , 
E [auth A],  F [auth A],  G [auth A],  H [auth A],  I [auth B],  J [auth C],  K [auth D],  L [auth D],  M [auth D]
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.223 
  • R-Value Observed: 0.227 
  • Space Group: P 63
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 226.882α = 90
b = 226.882β = 90
c = 118.853γ = 120
Software Package:
Software NamePurpose
CrystalCleardata reduction
AMoREphasing
CNSrefinement
CrystalCleardata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

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