1OLO

Hexameric Replicative DNA Helicase RepA from Plasmid RSF1010 - Cubic Crystal Structure


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.55 Å
  • R-Value Free: 0.211 
  • R-Value Work: 0.176 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Hexameric Rsf1010 Helicase Repa: The Structural and Functional Importance of Single Amino Acid Residues

Ziegelin, G.Niedenzu, T.Lurz, R.Saenger, W.Lanka, E.

(2003) Nucleic Acids Res. 31: 5917


  • PubMed Abstract: 
  • In the known monoclinic crystals the 3-dimensional structure of the hexameric, replicative helicase RepA encoded by plasmid RSF1010 shows 6-fold rotational symmetry. In contrast, in the cubic crystal form at 2.55 A resolution described here RepA has ...

    In the known monoclinic crystals the 3-dimensional structure of the hexameric, replicative helicase RepA encoded by plasmid RSF1010 shows 6-fold rotational symmetry. In contrast, in the cubic crystal form at 2.55 A resolution described here RepA has 3-fold symmetry and consists of a trimer of dimers. To study structure-function relationships, a series of repA deletion mutants and mutations yielding single amino acid exchanges were constructed and the respective gene products were analyzed in vivo and in vitro. Hexamerization of RepA occurs via the N-terminus and is required for NTP hydrolysis. The C-terminus is essential both for the interaction with the replication machinery and for the helicase activity. Functional analyses of RepA variants with single amino acid exchanges confirmed most of the predictions that were based on the published 3-dimensional structure. Of the five motifs conserved in family 4 helicases, all residues conserved in RepA and T7 gp4 helicases participate in DNA unwinding. Residues K42, E76, D77, D139 and H178, proposed to play key roles in catalyzing the hydrolysis of NTPs, are essential for RepA activity. Residue H178 of motif H3 couples nucleotide consumption to DNA strand separation.


    Organizational Affiliation

    Max-Planck-Institut für Molekulare Genetik, Ihnestrasse 73, Dahlem, D-14195 Berlin, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
REGULATORY PROTEIN REPA
A, B
279Escherichia coliGene 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
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.55 Å
  • R-Value Free: 0.211 
  • R-Value Work: 0.176 
  • Space Group: P 43 3 2
Unit Cell:
Length (Å)Angle (°)
a = 190.293α = 90.00
b = 190.293β = 90.00
c = 190.293γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-09-19
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Version format compliance
  • Version 1.2: 2017-06-28
    Type: Data collection