1CE9

HELIX CAPPING IN THE GCN4 LEUCINE ZIPPER


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.283 
  • R-Value Work: 0.214 

wwPDB Validation 3D Report Full Report


This is version 1.2 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: 10.1006/jmbi.1999.2707

  • 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, ...

    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.


    Related Citations: 
    • X-Ray Structure of the GCN4 Leucine Zipper, a Two-Stranded, Parallel Coiled Coil
      O'Shea, E.K.,Klemm, J.D.,Kim, P.S.,Alber, T.
      (1991) Science 254: 539


    Organizational Affiliation

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




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PROTEIN (GCN4-PMSE)
A, B, C, D
34Saccharomyces cerevisiae (strain ATCC 204508 / S288c)Gene Names: GCN4 (AAS3, ARG9)
Find proteins for P03069 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Go to UniProtKB:  P03069
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 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
DENZOdata reduction
AMoREphasing
SCALEPACKdata scaling
X-PLORrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1999-03-25
    Type: Initial release
  • Version 1.1: 2008-04-26
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance