4D9I

Crystal structure of holo Diaminopropionate ammonia lyase from Escherichia coli


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.192 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal Structure of Escherichia coli Diaminopropionate Ammonia-lyase Reveals Mechanism of Enzyme Activation and Catalysis

Bisht, S.Rajaram, V.Bharath, S.R.Kalyani, J.N.Khan, F.Rao, A.N.Savithri, H.S.Murthy, M.R.N.

(2012) J.Biol.Chem. 287: 20369-20381

  • DOI: 10.1074/jbc.M112.351809
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Pyridoxal 5'-phosphate (PLP)-dependent enzymes utilize the unique chemistry of a pyridine ring to carry out diverse reactions involving amino acids. Diaminopropionate (DAP) ammonia-lyase (DAPAL) is a prokaryotic PLP-dependent enzyme that catalyzes th ...

    Pyridoxal 5'-phosphate (PLP)-dependent enzymes utilize the unique chemistry of a pyridine ring to carry out diverse reactions involving amino acids. Diaminopropionate (DAP) ammonia-lyase (DAPAL) is a prokaryotic PLP-dependent enzyme that catalyzes the degradation of d- and l-forms of DAP to pyruvate and ammonia. Here, we report the first crystal structure of DAPAL from Escherichia coli (EcDAPAL) in tetragonal and monoclinic forms at 2.0 and 2.2 Å resolutions, respectively. Structures of EcDAPAL soaked with substrates were also determined. EcDAPAL has a typical fold type II PLP-dependent enzyme topology consisting of a large and a small domain with the active site at the interface of the two domains. The enzyme is a homodimer with a unique biological interface not observed earlier. Structure of the enzyme in the tetragonal form had PLP bound at the active site, whereas the monoclinic structure was in the apo-form. Analysis of the apo and holo structures revealed that the region around the active site undergoes transition from a disordered to ordered state and assumes a conformation suitable for catalysis only upon PLP binding. A novel disulfide was found to occur near a channel that is likely to regulate entry of ligands to the active site. EcDAPAL soaked with dl-DAP revealed density at the active site appropriate for the reaction intermediate aminoacrylate, which is consistent with the observation that EcDAPAL has low activity under crystallization conditions. Based on the analysis of the structure and results of site-directed mutagenesis, a two-base mechanism of catalysis involving Asp(120) and Lys(77) is suggested.


    Organizational Affiliation

    Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Diaminopropionate ammonia-lyase
A, B
398Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: ygeX
EC: 4.3.1.15
Find proteins for P66899 (Escherichia coli (strain K12))
Go to UniProtKB:  P66899
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
TRS
Query on TRS

Download SDF File 
Download CCD File 
A, B
2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL
TRIS BUFFER
C4 H12 N O3
LENZDBCJOHFCAS-UHFFFAOYSA-O
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
LLP
Query on LLP
A, B
L-PEPTIDE LINKINGC14 H22 N3 O7 PLYS
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.192 
  • Space Group: P 43 21 2
Unit Cell:
Length (Å)Angle (°)
a = 85.530α = 90.00
b = 85.530β = 90.00
c = 207.268γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data collection
PHASERphasing
REFMACrefinement
HKL-2000data reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-04-25
    Type: Initial release
  • Version 1.1: 2012-07-11
    Type: Database references
  • Version 1.2: 2017-05-10
    Type: Structure summary