1NLF

Crystal Structure of DNA Helicase RepA in complex with sulfate at 1.95 A resolution


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.242 
  • R-Value Work: 0.201 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Structure of DNA helicase RepA in complex with sulfate at 1.95 A resolution implicates structural changes to an "open" form.

Xu, H.Strater, N.Schroder, W.Bottcher, C.Ludwig, K.Saenger, W.

(2003) Acta Crystallogr.,Sect.D 59: 815-822


  • PubMed Abstract: 
  • The structure of a new crystal form (space group C2), grown at pH 8.0 and diffracting to 1.95 A resolution, of the replicative homo-hexameric DNA helicase RepA encoded by plasmid RSF1010 is reported. In contrast to previous crystals grown at pH 6.0 i ...

    The structure of a new crystal form (space group C2), grown at pH 8.0 and diffracting to 1.95 A resolution, of the replicative homo-hexameric DNA helicase RepA encoded by plasmid RSF1010 is reported. In contrast to previous crystals grown at pH 6.0 in space group P2(1) (Niedenzu et al., 2001), only one half (a trimer) of the RepA hexamer occupies the asymmetric unit of the space-group C2 crystals. The new crystal packing explains the pH-dependent hexamer-hexamer association mechanism of RepA. The C-terminus (264)VLERQRKSKGVPRGEA(279), which could not be modelled in the previous structure, is clearly defined in the present electron density except for the last four amino acids. Sulfate anions occupy the six ATPase active sites of RepA at positions where the product phosphates are supposed to bind. Binding of sulfate anions induces conformational changes both at the ATPase active sites and throughout the whole molecular structure. In agreement with electron microscopy, the above studies implicate structural changes to an "open" form that may occur upon binding and hydrolysis of nucleotide 5'-triphosphates and could be essential for DNA duplex-unwinding activity.


    Organizational Affiliation

    Institut für Kristallographie, Freie Universität Berlin, Takustrasse 6, D-14195 Berlin, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Regulatory protein repA
A, B, C
279Escherichia coliMutation(s): 0 
Gene Names: repA
Find proteins for P20356 (Escherichia coli)
Go to UniProtKB:  P20356
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A, B, C
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.242 
  • R-Value Work: 0.201 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 192.300α = 90.00
b = 55.300β = 122.90
c = 105.600γ = 90.00
Software Package:
Software NamePurpose
AMoREphasing
SCALEPACKdata scaling
MAR345data collection
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-04-29
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance
  • Version 1.3: 2017-10-11
    Type: Refinement description