1CZD

CRYSTAL STRUCTURE OF THE PROCESSIVITY CLAMP GP45 FROM BACTERIOPHAGE T4


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.259 
  • R-Value Work: 0.232 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal structure of the DNA polymerase processivity factor of T4 bacteriophage.

Moarefi, I.Jeruzalmi, D.Turner, J.O'Donnell, M.Kuriyan, J.

(2000) J.Mol.Biol. 296: 1215-1223

  • DOI: 10.1006/jmbi.1999.3511

  • PubMed Abstract: 
  • The protein encoded by gene 45 of T4 bacteriophage (gene 45 protein or gp45), is responsible for tethering the catalytic subunit of T4 DNA Polymerase to DNA during high-speed replication. Also referred to as a sliding DNA clamp, gp45 is similar in it ...

    The protein encoded by gene 45 of T4 bacteriophage (gene 45 protein or gp45), is responsible for tethering the catalytic subunit of T4 DNA Polymerase to DNA during high-speed replication. Also referred to as a sliding DNA clamp, gp45 is similar in its function to the processivity factors of bacterial and eukaryotic DNA polymerases, the beta-clamp and PCNA, respectively. Crystallographic analysis has shown that the beta-clamp and PCNA form highly symmetrical ring-shaped structures through which duplex DNA can be threaded. Gp45 shares no sequence similarity with beta-clamp or PCNA, and sequence comparisons have not been able to establish whether it adopts a similar structure. We have determined the crystal structure of gp45 from T4 bacteriophage at 2.4 A resolution, using multiple isomorphous replacement. The protein forms a trimeric ring-shaped assembly with overall dimensions that are similar to those of the bacterial and eukaryotic processivity factors. Each monomer of gp45 contains two domains that are very similar in chain fold to those of beta-clamp and PCNA. Despite an overall negative charge, the inner surface of the ring is in a region of positive electrostatic potential, consistent with a mechanism in which DNA is threaded through the ring.


    Organizational Affiliation

    Howard Hughes Medical Institute, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
DNA POLYMERASE ACCESSORY PROTEIN G45
A, B, C
228Enterobacteria phage T4Gene Names: 45
Find proteins for P04525 (Enterobacteria phage T4)
Go to UniProtKB:  P04525
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.259 
  • R-Value Work: 0.232 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 66.177α = 90.00
b = 93.938β = 90.00
c = 141.820γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
SCALEPACKdata scaling
DENZOdata reduction
MLPHAREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-03-03
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance