5IKN

Crystal Structure of the T7 Replisome in the Absence of DNA


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 4.802 Å
  • R-Value Free: 0.318 
  • R-Value Work: 0.275 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Hybrid Methods Reveal Multiple Flexibly Linked DNA Polymerases within the Bacteriophage T7 Replisome.

Wallen, J.R.Zhang, H.Weis, C.Cui, W.Foster, B.M.Ho, C.M.Hammel, M.Tainer, J.A.Gross, M.L.Ellenberger, T.

(2017) Structure 25: 157-166

  • DOI: 10.1016/j.str.2016.11.019

  • PubMed Abstract: 
  • The physical organization of DNA enzymes at a replication fork enables efficient copying of two antiparallel DNA strands, yet dynamic protein interactions within the replication complex complicate replisome structural studies. We employed a combinati ...

    The physical organization of DNA enzymes at a replication fork enables efficient copying of two antiparallel DNA strands, yet dynamic protein interactions within the replication complex complicate replisome structural studies. We employed a combination of crystallographic, native mass spectrometry and small-angle X-ray scattering experiments to capture alternative structures of a model replication system encoded by bacteriophage T7. Two molecules of DNA polymerase bind the ring-shaped primase-helicase in a conserved orientation and provide structural insight into how the acidic C-terminal tail of the primase-helicase contacts the DNA polymerase to facilitate loading of the polymerase onto DNA. A third DNA polymerase binds the ring in an offset manner that may enable polymerase exchange during replication. Alternative polymerase binding modes are also detected by small-angle X-ray scattering with DNA substrates present. Our collective results unveil complex motions within T7 replisome higher-order structures that are underpinned by multivalent protein-protein interactions with functional implications.


    Organizational Affiliation

    Department of Chemistry & Physics, Western Carolina University, Cullowhee, NC 28723, USA. Electronic address: jamiewallen@email.wcu.edu.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
DNA-directed DNA polymerase
A, B, C
704Enterobacteria phage T7EC: 2.7.7.7, 3.1.11.-
Find proteins for P00581 (Enterobacteria phage T7)
Go to UniProtKB:  P00581
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
DNA primase/helicase
D, E, F, G, H, I, J
486Enterobacteria phage T7EC: 3.6.4.12, 2.7.7.-
Find proteins for P03692 (Enterobacteria phage T7)
Go to UniProtKB:  P03692
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Thioredoxin-1
K, L, M
105Escherichia coli O157:H7Gene Names: trxA
Find proteins for P0AA27 (Escherichia coli O157:H7)
Go to UniProtKB:  P0AA27
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 4.802 Å
  • R-Value Free: 0.318 
  • R-Value Work: 0.275 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 174.866α = 90.00
b = 238.091β = 90.00
c = 243.466γ = 90.00
Software Package:
Software NamePurpose
PHENIXrefinement
PDB_EXTRACTdata extraction
HKL-2000data scaling
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationCountryGrant Number
National Institutes of Health/National Institute of General Medical SciencesUnited StatesGM055390

Revision History 

  • Version 1.0: 2016-12-07
    Type: Initial release
  • Version 1.1: 2017-01-18
    Type: Database references
  • Version 1.2: 2017-09-20
    Type: Author supporting evidence