6CRM

Crystal Structure of RecQ catalytic core from C. sakazakii bound to an unfolded G-quadruplex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.19286 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.205 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

A guanine-flipping and sequestration mechanism for G-quadruplex unwinding by RecQ helicases.

Voter, A.F.Qiu, Y.Tippana, R.Myong, S.Keck, J.L.

(2018) Nat Commun 9: 4201-4201

  • DOI: 10.1038/s41467-018-06751-8

  • PubMed Abstract: 
  • Homeostatic regulation of G-quadruplexes (G4s), four-stranded structures that can form in guanine-rich nucleic acids, requires G4 unwinding helicases. The mechanisms that mediate G4 unwinding remain unknown. We report the structure of a bacterial Rec ...

    Homeostatic regulation of G-quadruplexes (G4s), four-stranded structures that can form in guanine-rich nucleic acids, requires G4 unwinding helicases. The mechanisms that mediate G4 unwinding remain unknown. We report the structure of a bacterial RecQ DNA helicase bound to resolved G4 DNA. Unexpectedly, a guanine base from the unwound G4 is sequestered within a guanine-specific binding pocket. Disruption of the pocket in RecQ blocks G4 unwinding, but not G4 binding or duplex DNA unwinding, indicating its essential role in structure-specific G4 resolution. A novel guanine-flipping and sequestration model that may be applicable to other G4-resolving helicases emerges from these studies.


    Organizational Affiliation

    Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53706, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure


Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
RecQ
A
541Cronobacter sakazakii (strain ATCC BAA-894)Mutation(s): 0 
Find proteins for A7MQK9 (Cronobacter sakazakii (strain ATCC BAA-894))
Go to UniProtKB:  A7MQK9
Entity ID: 2
MoleculeChainsLengthOrganism
DNA (5'-D(P*GP*GP*GP*TP*CP*GP*GP*TP*GP*CP*CP*TP*TP*A)-3')B37synthetic construct
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
A
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.19286 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.205 
  • Space Group: P 21 21 2
Unit Cell:
Length (Å)Angle (°)
a = 78.468α = 90.00
b = 94.670β = 90.00
c = 98.906γ = 90.00
Software Package:
Software NamePurpose
XDSdata reduction
PHENIXrefinement
PHENIXmodel building
XDSdata scaling
PHENIXphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
NIHUnited StatesR01 GM098885

Revision History 

  • Version 1.0: 2018-10-17
    Type: Initial release
  • Version 1.1: 2018-10-24
    Type: Data collection, Database references