Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Cyclic - C6  (3D View)
Global Stoichiometry: Homo 6-mer - A6 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 176.80 kDa 
• Atom Count: 12258 
• Modelled Residue Count: 1530 
• Deposited Residue Count: 1542 
• Unique protein chains: 1

4POF

PfMCM N-terminal domain without DNA

• DOI: 10.2210/pdb4POF/pdb

• Classification: REPLICATION, DNA BINDING PROTEIN
• Organism(s): Pyrococcus furiosus DSM 3638
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2014-02-25 Released: 2014-04-09 
• Deposition Author(s): Froelich, C.A., Kang, S., Epling, L.B., Bell, S.P., Enemark, E.J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.65 Å
• R-Value Free: 0.270 
• R-Value Work: 0.259 
• R-Value Observed: 0.260 

Literature

A conserved MCM single-stranded DNA binding element is essential for replication initiation.

Froelich, C.A., Kang, S., Epling, L.B., Bell, S.P., Enemark, E.J.

(2014) Elife 3: e01993-e01993

• PubMed: 24692448 
• DOI: 10.7554/eLife.01993
• Primary Citation of Related Structures:  
  4POF, 4POG


• PubMed Abstract: 
  

The ring-shaped MCM helicase is essential to all phases of DNA replication. The complex loads at replication origins as an inactive double-hexamer encircling duplex DNA. Helicase activation converts this species to two active single hexamers that encircle single-stranded DNA (ssDNA). The molecular details of MCM DNA interactions during these events are unknown. We determined the crystal structure of the Pyrococcus furiosus MCM N-terminal domain hexamer bound to ssDNA and define a conserved MCM-ssDNA binding motif (MSSB). Intriguingly, ssDNA binds the MCM ring interior perpendicular to the central channel with defined polarity. In eukaryotes, the MSSB is conserved in several Mcm2-7 subunits, and MSSB mutant combinations in S. cerevisiae Mcm2-7 are not viable. Mutant Mcm2-7 complexes assemble and are recruited to replication origins, but are defective in helicase loading and activation. Our findings identify an important MCM-ssDNA interaction and suggest it functions during helicase activation to select the strand for translocation. DOI: http://dx.doi.org/10.7554/eLife.01993.001.

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Organizational Affiliation: 

Department of Structural Biology, St Jude Children's Research Hospital, Memphis, United States.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Cell division control protein 21	A, B, C, D, E, F	257	Pyrococcus furiosus DSM 3638	Mutation(s): 0  Gene Names: Cdc21, PF0482 EC: 3.6.4.12
Find proteins for Q8U3I4 (Pyrococcus furiosus (strain ATCC 43587 / DSM 3638 / JCM 8422 / Vc1)) Explore Q8U3I4  Go to UniProtKB:  Q8U3I4

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ZN	A, B, C, D, E, F	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.65 Å
• R-Value Free: 0.270 
• R-Value Work: 0.259 
• R-Value Observed: 0.260 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 122.849	α = 90
b = 103.064	β = 119.85
c = 122.435	γ = 90

Software Package:

Software Name	Purpose
SERGUI	data collection
PHASER	phasing
REFMAC	refinement
HKL-2000	data reduction
HKL-2000	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2014-02-25 
• Released Date: 2014-04-09 
Deposition Author(s): Froelich, C.A., Kang, S., Epling, L.B., Bell, S.P., Enemark, E.J.

Revision History  

• Version 1.0: 2014-04-09
  Type: Initial release
  
• Version 1.1: 2014-12-24
  Changes: Database references