6MCJ

Structure of Helical Carotenoid Protein 2 from Fremyella diplosiphon


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.712 Å
  • R-Value Free: 0.199 
  • R-Value Work: 0.167 

wwPDB Validation 3D Report Full Report


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Literature

Structural and spectroscopic characterization of HCP2.

Dominguez-Martin, M.A.Polivka, T.Sutter, M.Ferlez, B.Lechno-Yossef, S.Montgomery, B.L.Kerfeld, C.A.

(2019) Biochim Biophys Acta Bioenerg 1860: 414-424

  • DOI: 10.1016/j.bbabio.2019.03.004

  • PubMed Abstract: 
  • The Helical Carotenoid Proteins (HCPs) are a large group of newly identified carotenoid-binding proteins found in ecophysiologically diverse cyanobacteria. They likely evolved before becoming the effector (quenching) domain of the modular Orange Caro ...

    The Helical Carotenoid Proteins (HCPs) are a large group of newly identified carotenoid-binding proteins found in ecophysiologically diverse cyanobacteria. They likely evolved before becoming the effector (quenching) domain of the modular Orange Carotenoid Protein (OCP). The number of discrete HCP families-at least nine-suggests they are involved in multiple distinct functions. Here we report the 1.7 Å crystal structure of HCP2, one of the most widespread HCPs found in nature, from the chromatically acclimating cyanobacterium Tolypothrix sp. PCC 7601. By purifying HCP2 from the native source we are able to identify its natively-bound carotenoid, which is exclusively canthaxanthin. In solution, HCP2 is a monomer with an absorbance maximum of 530 nm. However, the HCP2 crystals have a maximum absorbance at 548 nm, which is accounted by the stacking of the β1 rings of the carotenoid in the two molecules in the asymmetric unit. Our results demonstrate how HCPs provide a valuable system to study carotenoid-protein interactions and their spectroscopic implications, and contribute to efforts to understand the functional roles of this large, newly discovered family of pigment proteins, which to-date remain enigmatic.


    Organizational Affiliation

    Institute of Physics, Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic.,MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA; Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.,MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA; Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA.,MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA.,MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA; Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA. Electronic address: ckerfeld@lbl.gov.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Orange carotenoid-binding protein
A, B
163Tolypothrix sp. PCC 7601Mutation(s): 0 
Find proteins for A0A0D6L0Q7 (Tolypothrix sp. PCC 7601)
Go to UniProtKB:  A0A0D6L0Q7
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
IOD
Query on IOD

Download SDF File 
Download CCD File 
A, B
IODIDE ION
I
XMBWDFGMSWQBCA-UHFFFAOYSA-M
 Ligand Interaction
45D
Query on 45D

Download SDF File 
Download CCD File 
A, B
beta,beta-carotene-4,4'-dione
Isomer of Canthaxanthin
C40 H52 O2
FDSDTBUPSURDBL-DKLMTRRASA-N
 Ligand Interaction
1PE
Query on 1PE

Download SDF File 
Download CCD File 
A
PENTAETHYLENE GLYCOL
PEG400
C10 H22 O6
JLFNLZLINWHATN-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.712 Å
  • R-Value Free: 0.199 
  • R-Value Work: 0.167 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 35.162α = 90.00
b = 71.635β = 92.32
c = 56.341γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
PHENIXrefinement
XDSdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2019-03-27
    Type: Initial release
  • Version 1.1: 2019-11-13
    Type: Database references