3R5H

Crystal Structure of ADP-AIR complex of purK: N5-carboxyaminoimidazole ribonucleotide synthetase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.179 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Elucidation of the bicarbonate binding site and insights into the carboxylation mechanism of (N(5))-carboxyaminoimidazole ribonucleotide synthase (PurK) from Bacillus anthracis

Tuntland, M.L.Santarsiero, B.D.Johnson, M.E.Fung, L.W.

(2014) Acta Crystallogr.,Sect.D 70: 3057-3065

  • DOI: 10.1107/S1399004714021166
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Structures of (N(5))-carboxyaminoimidazole ribonucleotide synthase (PurK) from Bacillus anthracis with various combinations of ATP, ADP, Mg(2+), bicarbonate and aminoimidazole ribonucleotide (AIR) in the active site are presented. The binding site of ...

    Structures of (N(5))-carboxyaminoimidazole ribonucleotide synthase (PurK) from Bacillus anthracis with various combinations of ATP, ADP, Mg(2+), bicarbonate and aminoimidazole ribonucleotide (AIR) in the active site are presented. The binding site of bicarbonate has only been speculated upon previously, but is shown here for the first time. The binding involves interactions with the conserved residues Arg272, His274 and Lys348. These structures provide insights into each ligand in the active site and allow a possible mechanism to be proposed for the reaction that converts bicarbonate and AIR, in the presence of ATP, to produce (N(5))-carboxyaminoimidazole ribonucleotide. The formation of a carboxyphosphate intermediate through ATP phosphoryl transfer is proposed, followed by carboxylation of AIR to give the product, facilitated by a cluster of conserved residues and an active-site water network.


    Organizational Affiliation

    Department of Chemistry, University of Illinois at Chicago, Chicago, IL 60607, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Phosphoribosylaminoimidazole carboxylase, ATPase subunit
A, B
389N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
AIR
Query on AIR

Download SDF File 
Download CCD File 
A, B
5-AMINOIMIDAZOLE RIBONUCLEOTIDE
C8 H14 N3 O7 P
PDACUKOKVHBVHJ-XVFCMESISA-N
 Ligand Interaction
ADP
Query on ADP

Download SDF File 
Download CCD File 
A, B
ADENOSINE-5'-DIPHOSPHATE
C10 H15 N5 O10 P2
XTWYTFMLZFPYCI-KQYNXXCUSA-N
 Ligand Interaction
MG
Query on MG

Download SDF File 
Download CCD File 
A, B
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.179 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 57.442α = 90.00
b = 82.785β = 90.00
c = 168.233γ = 90.00
Software Package:
Software NamePurpose
SERGUIdata collection
XSCALEdata scaling
PDB_EXTRACTdata extraction
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-03-21
    Type: Initial release
  • Version 1.1: 2015-03-18
    Type: Database references
  • Version 1.2: 2017-11-08
    Type: Refinement description