1GW4

THE HELIX-HINGE-HELIX STRUCTURAL MOTIF IN HUMAN APOLIPOPROTEIN A-I DETERMINED BY NMR SPECTROSCOPY, 1 STRUCTURE


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 
  • Selection Criteria: LOWER OPTIMIZATION ERROR AND NO DISTANCE VIOLATION GREATER THAN 0.5 A) 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The helix-hinge-helix structural motif in human apolipoprotein A-I determined by NMR spectroscopy.

Wang, G.Sparrow, J.T.Cushley, R.J.

(1997) Biochemistry 36: 13657-13666

  • DOI: 10.1021/bi971151q
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The conformation of a synthetic peptide of 46 residues from apoA-I was investigated by fluorescence, CD, and 2D NMR spectroscopies in lipid-mimetic environments. ApoA-I(142-187) is mainly unstructured in water but helical in SDS or dodecylphosphochol ...

    The conformation of a synthetic peptide of 46 residues from apoA-I was investigated by fluorescence, CD, and 2D NMR spectroscopies in lipid-mimetic environments. ApoA-I(142-187) is mainly unstructured in water but helical in SDS or dodecylphosphocholine (DPC), although the peptide only associates with DPC at approximately the critical micellar concentration. Solution structures of apoA-I(142-187) were determined by distance geometry calculations based on 450 (in DPC-d38) or 397 (in SDS-d25) NOE-derived distance restraints, respectively. Backbone RMSDs for superimposing the two helical regions 146-162 and 168-182 are 0.98 +/- 0.22 (2.38 +/- 0.20) and 1.99 +/- 0.42 (2.02 +/- 0.21) A in DPC (SDS), respectively. No interhelical NOE was found, suggesting that helix-helix interactions between the two helical domains in apoA-I(142-187) are unlikely. Similar average, curved helix-hinge-helix structures were found in both SDS and DPC micelles with the hydrophobic residues occupying the concave face, indicating that hydrophobic interactions dominate. Intermolecular NOESY experiments, performed in the presence of 50% protonated SDS, confirm that the two amphipathic helices and Y166 in the hinge all interact with the micelle. The involvement of Y166 in lipid binding is supported by fluorescence spectroscopy as well. On the basis of all the data above, we propose a model for the peptide-lipid complexes wherein the curved amphipathic helix-hinge-helix structural motif straddles the micelle. The peptide-aided signal assignment achieved for apoA-I(122-187) (66mer) and apoA-I suggests that such a structural motif is retained in the longer peptide and most likely in the intact protein.


    Organizational Affiliation

    Institute of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
APOA-I
A
46Homo sapiensMutation(s): 0 
Gene Names: APOA1
Find proteins for P02647 (Homo sapiens)
Go to Gene View: APOA1
Go to UniProtKB:  P02647
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 
  • Selection Criteria: LOWER OPTIMIZATION ERROR AND NO DISTANCE VIOLATION GREATER THAN 0.5 A) 

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1997-07-23
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance