2BB0

Structure of Imidazolonepropionase from Bacillus subtilis


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.188 
  • R-Value Observed: 0.191 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

A catalytic mechanism revealed by the crystal structures of the imidazolonepropionase from Bacillus subtilis

Yu, Y.Liang, Y.H.Brostromer, E.Quan, J.M.Panjikar, S.Dong, Y.H.Su, X.D.

(2006) J Biol Chem 281: 36929-36936

  • DOI: 10.1074/jbc.M607703200
  • Primary Citation of Related Structures:  
    2G3F, 2BB0

  • PubMed Abstract: 
  • Imidazolonepropionase (EC 3.5.2.7) catalyzes the third step in the universal histidine degradation pathway, hydrolyzing the carbon-nitrogen bonds in 4-imidazolone-5-propionic acid to yield N-formimino-l-glutamic acid. Here we report the crystal struc ...

    Imidazolonepropionase (EC 3.5.2.7) catalyzes the third step in the universal histidine degradation pathway, hydrolyzing the carbon-nitrogen bonds in 4-imidazolone-5-propionic acid to yield N-formimino-l-glutamic acid. Here we report the crystal structures of the Bacillus subtilis imidazolonepropionase and its complex at 2.0-A resolution with substrate analog imidazole-4-acetic acid sodium (I4AA). The structure of the native enzyme contains two domains, a TIM (triose-phosphate isomerase) barrel domain with two insertions and a small beta-sandwich domain. The TIM barrel domain is quite similar to the members of the alpha/beta barrel metallo-dependent hydrolase superfamily, especially to Escherichia coli cytosine deaminase. A metal ion was found in the central cavity of the TIM barrel and was tightly coordinated to residues His-80, His-82, His-249, Asp-324, and a water molecule. X-ray fluorescence scan analysis confirmed that the bound metal ion was a zinc ion. An acetate ion, 6 A away from the zinc ion, was also found in the potential active site. In the complex structure with I4AA, a substrate analog, I4AA replaced the acetate ion and contacted with Arg-89, Try-102, Tyr-152, His-185, and Glu-252, further defining and confirming the active site. The detailed structural studies allowed us to propose a zinc-activated nucleophilic attack mechanism for the hydrolysis reaction catalyzed by the enzyme.


    Organizational Affiliation

    The National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871, China.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
ImidazolonepropionaseAB421Bacillus subtilisMutation(s): 0 
EC: 3.5.2.7
Find proteins for P42084 (Bacillus subtilis (strain 168))
Explore P42084 
Go to UniProtKB:  P42084
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download CCD File 
A, B
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
ACT
Query on ACT

Download CCD File 
A, B
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.188 
  • R-Value Observed: 0.191 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 57.73α = 90
b = 106.34β = 89.92
c = 66.47γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
SHELXphasing
DMphasing
CNSrefinement
PDB_EXTRACTdata extraction
MAR345data collection
SHELXDphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-09-26
    Type: Initial release
  • Version 1.1: 2008-05-01
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Version format compliance
  • Version 1.3: 2017-10-11
    Changes: Refinement description