1E0J

gp4d helicase from phage T7 ADPNP complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Free: 0.304 
  • R-Value Work: 0.253 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal Structure of T7 Gene 4 Ring Helicase Indicates a Mechanism for Sequential Hydrolysis of Nucleotides

Singleton, M.R.Sawaya, M.R.Ellenberger, T.Wigley, D.B.

(2000) Cell 101: 589

  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • We have determined the crystal structure of an active, hexameric fragment of the gene 4 helicase from bacteriophage T7. The structure reveals how subunit contacts stabilize the hexamer. Deviation from expected six-fold symmetry of the hexamer indicat ...

    We have determined the crystal structure of an active, hexameric fragment of the gene 4 helicase from bacteriophage T7. The structure reveals how subunit contacts stabilize the hexamer. Deviation from expected six-fold symmetry of the hexamer indicates that the structure is of an intermediate on the catalytic pathway. The structural consequences of the asymmetry suggest a "binding change" mechanism to explain how cooperative binding and hydrolysis of nucleotides are coupled to conformational changes in the ring that most likely accompany duplex unwinding. The structure of a complex with a nonhydrolyzable ATP analog provides additional evidence for this hypothesis, with only four of the six possible nucleotide binding sites being occupied in this conformation of the hexamer. This model suggests a mechanism for DNA translocation.


    Organizational Affiliation

    Sir William Dunn School of Pathology, University of Oxford, United Kingdom.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
DNA HELICASE
A, B, C, D, E, F
289Enterobacteria phage T7Mutation(s): 0 
EC: 2.7.7.-, 3.6.4.12
Find proteins for P03692 (Enterobacteria phage T7)
Go to UniProtKB:  P03692
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ANP
Query on ANP

Download SDF File 
Download CCD File 
A, B, D, E
PHOSPHOAMINOPHOSPHONIC ACID-ADENYLATE ESTER
C10 H17 N6 O12 P3
PVKSNHVPLWYQGJ-KQYNXXCUSA-N
 Ligand Interaction
MG
Query on MG

Download SDF File 
Download CCD File 
A, B, D, E
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Free: 0.304 
  • R-Value Work: 0.253 
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 119.180α = 90.00
b = 119.180β = 90.00
c = 283.420γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
SCALEPACKdata scaling
CNSphasing
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-06-09
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance