1IOJ

HUMAN APOLIPOPROTEIN C-I, NMR, 18 STRUCTURES


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 18 
  • Selection Criteria: SELECTED STRUCTURES HAVE NO HELIX-HELIX CONTACTS <5 ANGSTROMS 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Conformation of human apolipoprotein C-I in a lipid-mimetic environment determined by CD and NMR spectroscopy.

Rozek, A.Sparrow, J.T.Weisgraber, K.H.Cushley, R.J.

(1999) Biochemistry 38: 14475-14484

  • DOI: https://doi.org/10.1021/bi982966h
  • Primary Citation of Related Structures:  
    1IOJ

  • PubMed Abstract: 

    The high-resolution conformation of human apoC-I in complexes with sodium dodecyl sulfate (SDS) is presented. As estimated from CD data, apoC-I adopts 54% helical secondary structure when bound to SDS, which is similar to the helical content previously found with phospholipids. The NMR-derived conformation of apoC-I is composed of two amphipathic helices, residues 7-29 and 38-52, separated by a flexible linker. The N-terminal helix contains a mobile hinge involving residues 12-15. The hydrophobic side chains cluster on the nonpolar face of both helices, thus forming two discrete lipid-binding sites in the N-terminal helix and one in the C-terminal helix. As suggested by amide proton resonance line widths and deuterium exchange rates, the N-terminal helix is more flexible and may bind less tightly to the detergent than the C-terminal helix. The different mobility of both helices appears to be related to side-chain composition, rather than length of the amphipathic helix, and may play a role in the function of apoC-I as an activator of lecithin:cholesterol acyltransferase (LCAT). A model is suggested in which the C-terminal helix serves as a lipid anchor while the N-terminal helix may hinge off the lipid surface to make specific contacts with LCAT.


  • Organizational Affiliation

    Department of Chemistry and Institute of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia Canada.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
APOC-I57Homo sapiensMutation(s): 0 
Membrane Entity: Yes 
UniProt & NIH Common Fund Data Resources
Find proteins for P02654 (Homo sapiens)
Explore P02654 
Go to UniProtKB:  P02654
PHAROS:  P02654
GTEx:  ENSG00000130208 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP02654
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 18 
  • Selection Criteria: SELECTED STRUCTURES HAVE NO HELIX-HELIX CONTACTS <5 ANGSTROMS 

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1998-08-12
    Type: Initial release
  • Version 1.1: 2008-03-04
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2018-03-14
    Changes: Data collection, Derived calculations, Experimental preparation, Other, Refinement description, Source and taxonomy, Structure summary
  • Version 1.4: 2024-05-01
    Changes: Data collection, Database references