3UMP

Crystal structure of the Phosphofructokinase-2 from Escherichia coli in complex with Cesium and ATP


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.849 Å
  • R-Value Free: 0.209 
  • R-Value Work: 0.172 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

A Ribokinase Family Conserved Monovalent Cation Binding Site Enhances the MgATP-induced Inhibition in E. coli Phosphofructokinase-2

Baez, M.Cabrera, R.Pereira, H.M.Blanco, A.Villalobos, P.Ramirez-Sarmiento, C.A.Caniuguir, A.Guixe, V.Garratt, R.C.Babul, J.

(2013) Biophys.J. 105: 185-193

  • DOI: 10.1016/j.bpj.2013.05.028
  • Primary Citation of Related Structures:  3UMO

  • PubMed Abstract: 
  • The presence of a regulatory site for monovalent cations that affects the conformation of the MgATP-binding pocket leading to enzyme activation has been demonstrated for ribokinases. This site is selective toward the ionic radius of the monovalent ca ...

    The presence of a regulatory site for monovalent cations that affects the conformation of the MgATP-binding pocket leading to enzyme activation has been demonstrated for ribokinases. This site is selective toward the ionic radius of the monovalent cation, accepting those larger than Na(+). Phosphofructokinase-2 (Pfk-2) from Escherichia coli is homologous to ribokinase, but unlike other ribokinase family members, presents an additional site for the nucleotide that negatively regulates its enzymatic activity. In this work, we show the effect of monovalent cations on the kinetic parameters of Pfk-2 together with its three-dimensional structure determined by x-ray diffraction in the presence of K(+) or Cs(+). Kinetic characterization of the enzyme shows that K(+) and Na(+) alter neither the kcat nor the KM values for fructose-6-P or MgATP. However, the presence of K(+) (but not Na(+)) enhances the allosteric inhibition induced by MgATP. Moreover, binding experiments show that K(+) (but not Na(+)) increases the affinity of MgATP in a saturable fashion. In agreement with the biochemical data, the crystal structure of Pfk-2 obtained in the presence of MgATP shows a cation-binding site at the conserved position predicted for the ribokinase family of proteins. This site is adjacent to the MgATP allosteric binding site and is only observed in the presence of Cs(+) or K(+). These results indicate that binding of the monovalent metal ions indirectly influences the allosteric site of Pfk-2 by increasing its affinity for MgATP with no alteration in the conformation of residues present at the catalytic site.


    Organizational Affiliation

    Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
6-phosphofructokinase isozyme 2
A, B
309Escherichia coli (strain K12)Gene Names: pfkB
EC: 2.7.1.11
Find proteins for P06999 (Escherichia coli (strain K12))
Go to UniProtKB:  P06999
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ATP
Query on ATP

Download SDF File 
Download CCD File 
A, B
ADENOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O13 P3
ZKHQWZAMYRWXGA-KQYNXXCUSA-N
 Ligand Interaction
MG
Query on MG

Download SDF File 
Download CCD File 
A, B
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
CS
Query on CS

Download SDF File 
Download CCD File 
A, B
CESIUM ION
Cs
NCMHKCKGHRPLCM-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
ATPKi: 1026000 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.849 Å
  • R-Value Free: 0.209 
  • R-Value Work: 0.172 
  • Space Group: P 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 43.856α = 90.00
b = 88.914β = 90.00
c = 176.405γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
PHENIXrefinement
XSCALEdata scaling
DNAdata collection
XDSdata reduction
PDB_EXTRACTdata extraction
DMphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-11-14
    Type: Initial release
  • Version 1.1: 2013-07-24
    Type: Database references