1OLM

Supernatant Protein Factor in Complex with RRR-alpha-Tocopherylquinone: A Link between Oxidized Vitamin E and Cholesterol Biosynthesis


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.211 
  • R-Value Work: 0.180 
  • R-Value Observed: 0.181 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Supernatant Protein Factor in Complex with Rrr-Alpha-Tocopherylquinone: A Link between Oxidized Vitamin E and Cholesterol Biosynthesis

Stocker, A.Baumann, U.

(2003) J Mol Biol 332: 759

  • DOI: 10.1016/s0022-2836(03)00924-0
  • Primary Citation of Related Structures:  
    1OLM

  • PubMed Abstract: 
  • The vast majority of monomeric lipid transport in nature is performed by lipid-specific protein carriers. This class of proteins can enclose cognate lipid molecules in a hydrophobic cavity and transport them across the aqueous environment. Supernatant protein factor (SPF) is an enigmatic representative of monomeric lipid transporters belonging to the SEC14 family ...

    The vast majority of monomeric lipid transport in nature is performed by lipid-specific protein carriers. This class of proteins can enclose cognate lipid molecules in a hydrophobic cavity and transport them across the aqueous environment. Supernatant protein factor (SPF) is an enigmatic representative of monomeric lipid transporters belonging to the SEC14 family. SPF stimulates squalene epoxidation, a downstream step of the cholesterol biosynthetic pathway, by an unknown mechanism. Here, we present the three-dimensional crystal structure of human SPF in complex with RRR-alpha-tocopherylquinone, the major physiological oxidation product of RRR-alpha-tocopherol, at a resolution of 1.95A. The structure of the complex reveals how SPF sequesters RRR-alpha-tocopherylquinone (RRR-alpha-TQ) in its protein body and permits a comparison with the recently solved structure of human alpha-tocopherol transfer protein (alpha-TTP) in complex with RRR-alpha-tocopherol. Recent findings have shown that RRR-alpha-TQ is reduced in vivo to RRR-alpha-TQH(2), the latter has been suggested to protect low-density lipoprotein (LDL) particles from oxidation. Hence, the antioxidant function of the redox couple RRR-alpha-TQ/RRR-alpha-TQH(2) in blocking LDL oxidation may reduce cellular cholesterol uptake and thus explain how SPF upregulates cholesterol synthesis.


    Organizational Affiliation

    Department of Chemistry and Biochemistry, University of Berne, 3012 Bern, Switzerland. achim.stocker@ibc.unibe.ch



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
SEC14-LIKE PROTEIN 2A, B [auth C]403Homo sapiensMutation(s): 0 
Gene Names: SEC14L2C22orf6KIAA1186KIAA1658
UniProt & NIH Common Fund Data Resources
Find proteins for O76054 (Homo sapiens)
Explore O76054 
Go to UniProtKB:  O76054
PHAROS:  O76054
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
SEC14-LIKE PROTEIN 2C [auth E]403Homo sapiensMutation(s): 0 
Gene Names: SEC14L2C22orf6KIAA1186KIAA1658
UniProt & NIH Common Fund Data Resources
Find proteins for O76054 (Homo sapiens)
Explore O76054 
Go to UniProtKB:  O76054
PHAROS:  O76054
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
VTQ (Subject of Investigation/LOI)
Query on VTQ

Download Ideal Coordinates CCD File 
D [auth A], E [auth C], F [auth E]RRR-ALPHA-TOCOPHERYLQUINONE
C29 H50 O3
LTVDFSLWFKLJDQ-IEOSBIPESA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.211 
  • R-Value Work: 0.180 
  • R-Value Observed: 0.181 
  • Space Group: P 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 60.856α = 116.2
b = 84.621β = 102.64
c = 87.452γ = 100.24
Software Package:
Software NamePurpose
REFMACrefinement
XDSdata reduction
XDSdata scaling
XSCALEdata scaling
CNSphasing

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2004-08-12
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance