1CE9

HELIX CAPPING IN THE GCN4 LEUCINE ZIPPER


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free: 0.283 
  • R-Value Work: 0.214 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Helix capping in the GCN4 leucine zipper.

Lu, M.Shu, W.Ji, H.Spek, E.Wang, L.Kallenbach, N.R.

(1999) J Mol Biol 288: 743-752

  • DOI: https://doi.org/10.1006/jmbi.1999.2707
  • Primary Citation of Related Structures:  
    1CE9

  • PubMed Abstract: 

    Capping interactions associated with specific sequences at or near the ends of alpha-helices are important determinants of the stability of protein secondary and tertiary structure. We investigate here the role of the helix-capping motif Ser-X-X-Glu, a sequence that occurs frequently at the N termini of alpha helices in proteins, on the conformation and stability of the GCN4 leucine zipper. The 1.8 A resolution crystal structure of the capped molecule reveals distinct conformations, packing geometries and hydrogen-bonding networks at the amino terminus of the two helices in the leucine zipper dimer. The free energy of helix stabilization associated with the hydrogen-bonding and hydrophobic interactions in this capping structure is -1.2 kcal/mol, evaluated from thermal unfolding experiments. A single cap thus contributes appreciably to stabilizing the terminated helix and thereby the native state. These results suggest that helix capping plays a further role in protein folding, providing a sensitive connector linking alpha-helix formation to the developing tertiary structure of a protein.


  • Organizational Affiliation

    Department of Biochemistry, Weill Medical College of Cornell University, New York, NY, 10021, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
PROTEIN (GCN4-PMSE)
A, B, C, D
34Saccharomyces cerevisiae (strain ATCC 204508 / S288c)Mutation(s): 0 
Gene Names: GCN4
UniProt
Find proteins for P03069 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Explore P03069 
Go to UniProtKB:  P03069
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP03069
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free: 0.283 
  • R-Value Work: 0.214 
  • Space Group: P 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 28.304α = 75.41
b = 30.769β = 79.76
c = 42.884γ = 90.08
Software Package:
Software NamePurpose
AMoREphasing
X-PLORrefinement
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1999-03-25
    Type: Initial release
  • Version 1.1: 2008-04-26
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Version format compliance
  • Version 1.3: 2023-08-09
    Changes: Data collection, Database references, Refinement description