1GM5

Structure of RecG bound to three-way DNA junction

• PDB DOI: https://doi.org/10.2210/pdb1GM5/pdb
• NAKB: 1GM5

• Classification: HELICASE
• Organism(s): Thermotoga maritima
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2001-09-11 Released: 2001-10-03 
• Deposition Author(s): Singleton, M.R., Scaife, S., Wigley, D.B.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.24 Å
• R-Value Free: 0.328 
• R-Value Work: 0.272 
• R-Value Observed: 0.275 

Literature

Structural Analysis of DNA Replication Fork Reversal by Recg

Singleton, M.R., Scaife, S., Wigley, D.B.

(2001) Cell 107: 79

• PubMed: 11595187 
• DOI: https://doi.org/10.1016/s0092-8674(01)00501-3
• Primary Citation of Related Structures:  
  1GM5


• PubMed Abstract: 
  

  The stalling of DNA replication forks that occurs as a consequence of encountering DNA damage is a critical problem for cells. RecG protein is involved in the processing of stalled replication forks, and acts by reversing the fork past the damage to create a four-way junction that allows template switching and lesion bypass. We have determined the crystal structure of RecG bound to a DNA substrate that mimics a stalled replication fork. The structure not only reveals the elegant mechanism used by the protein to recognize junctions but has also trapped the protein in the initial stage of fork reversal. We propose a mechanism for how forks are processed by RecG to facilitate replication fork restart. In addition, this structure suggests that the mechanism and function of the two largest helicase superfamilies are distinct.

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Organizational Affiliation: 

ICRF Clare Hall Laboratories, Blanche Lane, South Mimms, Potters Bar, Hertfordshire EN6 3LD, United Kingdom.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

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

Macromolecule Content

• Total Structure Weight: 105.54 kDa 
• Atom Count: 6,779 
• Modelled Residue Count: 770 
• Deposited Residue Count: 829 
• Unique protein chains: 1
• Unique nucleic acid chains: 3

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
RECG	A	780	Thermotoga maritima	Mutation(s): 0  EC: 3.6.4.12
UniProt
Find proteins for Q9WY48 (Thermotoga maritima (strain ATCC 43589 / DSM 3109 / JCM 10099 / NBRC 100826 / MSB8)) Explore Q9WY48  Go to UniProtKB:  Q9WY48

Entity ID: 2
Molecule	Chains	Length	Organism	Image
DNA (5'-(*CP*AP*GP*CP*TP*CP*CP*AP*TP*GP*AP*TP* CP*AP*TP*TP*GP*GP*CP*A)-3')	B [auth X]	20	N/A

Entity ID: 3
Molecule	Chains	Length	Organism	Image
DNA (5'-(*GP*CP*AP*GP*TP*GP*CP*TP*CP*GP*CP*AP* TP*GP*GP*AP*GP*CP*TP*G)-3')	C [auth Y]	20	N/A

Entity ID: 4
Molecule	Chains	Length	Organism	Image
DNA (5'-(*GP*AP*GP*CP*AP*CP*TP*GP*C)-3')	D [auth Z]	9	N/A

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ADP	E [auth A]	ADENOSINE-5'-DIPHOSPHATE C10 H15 N5 O10 P2 XTWYTFMLZFPYCI-KQYNXXCUSA-N
MG	F [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.24 Å
• R-Value Free: 0.328 
• R-Value Work: 0.272 
• R-Value Observed: 0.275 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 133.704	α = 90
b = 144.602	β = 113.82
c = 84.023	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement

Structure Validation

Entry History 

Deposition Data

• Released Date: 2001-10-03 
Deposition Author(s): Singleton, M.R., Scaife, S., Wigley, D.B.

Revision History  

• Version 1.0: 2001-10-03
  Type: Initial release
  
• Version 1.1: 2011-05-08
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2024-10-23
  Changes: Data collection, Database references, Derived calculations, Other, Structure summary