3TWY

RAT PKC C2 DOMAIN BOUND TO PB


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.204 

wwPDB Validation 3D Report Full Report


This is version 1.0 of the entry. See complete history

Literature

Pb2+ as Modulator of Protein-Membrane Interactions.

Morales, K.A.Lasagna, M.Gribenko, A.V.Yoon, Y.Reinhart, G.D.Lee, J.C.Cho, W.Li, P.Igumenova, T.I.

(2011) J.Am.Chem.Soc. 133: 10599

  • DOI: 10.1021/ja2032772
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Lead is a potent environmental toxin that mimics the effects of divalent metal ions, such as zinc and calcium, in the context of specific molecular targets and signaling processes. The molecular mechanism of lead toxicity remains poorly understood. T ...

    Lead is a potent environmental toxin that mimics the effects of divalent metal ions, such as zinc and calcium, in the context of specific molecular targets and signaling processes. The molecular mechanism of lead toxicity remains poorly understood. The objective of this work was to characterize the effect of Pb(2+) on the structure and membrane-binding properties of C2α. C2α is a peripheral membrane-binding domain of Protein Kinase Cα (PKCα), which is a well-documented molecular target of lead. Using NMR and isothermal titration calorimetry (ITC) techniques, we established that C2α binds Pb(2+) with higher affinity than its natural cofactor, Ca(2+). To gain insight into the coordination geometry of protein-bound Pb(2+), we determined the crystal structures of apo and Pb(2+)-bound C2α at 1.9 and 1.5 Å resolution, respectively. A comparison of these structures revealed that the metal-binding site is not preorganized and that rotation of the oxygen-donating side chains is required for the metal coordination to occur. Remarkably, we found that holodirected and hemidirected coordination geometries for the two Pb(2+) ions coexist within a single protein molecule. Using protein-to-membrane Förster resonance energy transfer (FRET) spectroscopy, we demonstrated that Pb(2+) displaces Ca(2+) from C2α in the presence of lipid membranes through the high-affinity interaction with the membrane-unbound C2α. In addition, Pb(2+) associates with phosphatidylserine-containing membranes and thereby competes with C2α for the membrane-binding sites. This process can contribute to the inhibitory effect of Pb(2+) on the PKCα activity.


    Organizational Affiliation

    Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Protein kinase C alpha type
A
137Rattus norvegicusMutation(s): 0 
Gene Names: Prkca (Pkca)
EC: 2.7.11.13
Find proteins for P05696 (Rattus norvegicus)
Go to UniProtKB:  P05696
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
PB
Query on PB

Download SDF File 
Download CCD File 
A
LEAD (II) ION
Pb
RVPVRDXYQKGNMQ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.204 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 58.290α = 90.00
b = 58.290β = 90.00
c = 87.980γ = 120.00
Software Package:
Software NamePurpose
MOLREPphasing
HKL-2000data scaling
HKL-2000data reduction
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2011-09-22 
  • Released Date: 2011-11-02 
  • Deposition Author(s): Li, P.
  • This entry supersedes: 3RDL

Revision History 

  • Version 1.0: 2011-11-02
    Type: Initial release