4N6S

Crystals of cross-linked stabilized and functional Phycobilisomes: only phycocyanin rods contribute to diffraction.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.235 
  • R-Value Work: 0.192 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural studies show energy transfer within stabilized phycobilisomes independent of the mode of rod-core assembly.

David, L.Prado, M.Arteni, A.A.Elmlund, D.A.Blankenship, R.E.Adir, N.

(2014) Biochim.Biophys.Acta 1837: 385-395

  • DOI: 10.1016/j.bbabio.2013.12.014

  • PubMed Abstract: 
  • The major light harvesting complex in cyanobacteria and red algae is the phycobilisome (PBS), comprised of hundreds of seemingly similar chromophores, which are protein bound and assembled in a fashion that enables highly efficient uni-directional en ...

    The major light harvesting complex in cyanobacteria and red algae is the phycobilisome (PBS), comprised of hundreds of seemingly similar chromophores, which are protein bound and assembled in a fashion that enables highly efficient uni-directional energy transfer to reaction centers. The PBS is comprised of a core containing 2-5 cylinders surrounded by 6-8 rods, and a number of models have been proposed describing the PBS structure. One of the most critical steps in the functionality of the PBS is energy transfer from the rod substructures to the core substructure. In this study we compare the structural and functional characteristics of high-phosphate stabilized PBS (the standard fashion of stabilization of isolated complexes) with cross-linked PBS in low ionic strength buffer from two cyanobacterial species, Thermosynechococcus vulcanus and Acaryochloris marina. We show that chemical cross-linking preserves efficient energy transfer from the phycocyanin containing rods to the allophycocyanin containing cores with fluorescent emission from the terminal emitters. However, this energy transfer is shown to exist in PBS complexes of different structures as characterized by determination of a 2.4Å structure by X-ray crystallography, single crystal confocal microscopy, mass spectrometry and transmission electron microscopy of negatively stained and cryogenically preserved complexes. We conclude that the PBS has intrinsic structural properties that enable efficient energy transfer from rod substructures to the core substructures without requiring a single unique structure. We discuss the significance of our observations on the functionality of the PBS in vivo.


    Organizational Affiliation

    Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
C-phycocyanin alpha subunit
A
162Thermosynechococcus vulcanusN/A
Find proteins for Q9AM02 (Thermosynechococcus vulcanus)
Go to UniProtKB:  Q9AM02
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
C-phycocyanin beta subunit
B
172Thermosynechococcus vulcanusN/A
Find proteins for Q71RW8 (Thermosynechococcus vulcanus)
Go to UniProtKB:  Q71RW8
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CYC
Query on CYC

Download SDF File 
Download CCD File 
A, B
PHYCOCYANOBILIN
C33 H40 N4 O6
VXTXPYZGDQPMHK-GMXXPEQVSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MEN
Query on MEN
B
L-PEPTIDE LINKINGC5 H10 N2 O3ASN
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.235 
  • R-Value Work: 0.192 
  • Space Group: H 3 2
Unit Cell:
Length (Å)Angle (°)
a = 188.070α = 90.00
b = 188.070β = 90.00
c = 60.380γ = 120.00
Software Package:
Software NamePurpose
MOSFLMdata reduction
PHASERphasing
SCALAdata scaling
CNSrefinement
DNAdata collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-01-22
    Type: Initial release
  • Version 1.1: 2014-02-12
    Type: Database references