6SCE

Structure of a Type III CRISPR defence DNA nuclease activated by cyclic oligoadenylate


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.83 Å
  • R-Value Free: 0.209 
  • R-Value Work: 0.176 

wwPDB Validation 3D Report Full Report


This is version 1.0 of the entry. See complete history

Literature

Structure and mechanism of a Type III CRISPR defence DNA nuclease activated by cyclic oligoadenylate.

McMahon, S.A.Zhu, W.Graham, S.Rambo, R.White, M.F.Gloster, T.M.

(2020) Nat Commun 11: 500-500

  • DOI: 10.1038/s41467-019-14222-x

  • PubMed Abstract: 
  • The CRISPR system provides adaptive immunity against mobile genetic elements in prokaryotes. On binding invading RNA species, Type III CRISPR systems generate cyclic oligoadenylate (cOA) signalling molecules, potentiating a powerful immune response b ...

    The CRISPR system provides adaptive immunity against mobile genetic elements in prokaryotes. On binding invading RNA species, Type III CRISPR systems generate cyclic oligoadenylate (cOA) signalling molecules, potentiating a powerful immune response by activating downstream effector proteins, leading to viral clearance, cell dormancy or death. Here we describe the structure and mechanism of a cOA-activated CRISPR defence DNA endonuclease, CRISPR ancillary nuclease 1 (Can1). Can1 has a unique monomeric structure with two CRISPR associated Rossman fold (CARF) domains and two DNA nuclease-like domains. The crystal structure of the enzyme has been captured in the activated state, with a cyclic tetra-adenylate (cA 4 ) molecule bound at the core of the protein. cA 4 binding reorganises the structure to license a metal-dependent DNA nuclease activity specific for nicking of supercoiled DNA. DNA nicking by Can1 is predicted to slow down viral replication kinetics by leading to the collapse of DNA replication forks.


    Organizational Affiliation

    Biomedical Sciences Research Complex, School of Biology, University of St Andrews, North Haugh, St Andrews, KY16 9ST, UK.,Diamond Light Source Ltd, Diamond House, Harwell Science and Innovation Campus, Fermi Ave, Didcot, OX11 0DE, UK.,Biomedical Sciences Research Complex, School of Biology, University of St Andrews, North Haugh, St Andrews, KY16 9ST, UK. mfw2@st-andrews.ac.uk.,Biomedical Sciences Research Complex, School of Biology, University of St Andrews, North Haugh, St Andrews, KY16 9ST, UK. tmg@st-andrews.ac.uk.




Macromolecules

Find similar proteins by: Sequence  |  Structure


Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Uncharacterized protein
A
638Thermus thermophilus (strain HB8 / ATCC 27634 / DSM 579)Mutation(s): 0 
Find proteins for Q53W14 (Thermus thermophilus (strain HB8 / ATCC 27634 / DSM 579))
Go to UniProtKB:  Q53W14
Entity ID: 2
MoleculeChainsLengthOrganism
cyclic oligoadenylateB4synthetic construct
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A
L-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.83 Å
  • R-Value Free: 0.209 
  • R-Value Work: 0.176 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 84.370α = 90.00
b = 84.520β = 90.00
c = 123.100γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
xia2data reduction
xia2data scaling
AutoSolphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Biotechnology and Biological Sciences Research CouncilUnited KingdomBB/R008035/1
Biotechnology and Biological Sciences Research CouncilUnited KingdomBB/S000313/1

Revision History 

  • Version 1.0: 2020-02-19
    Type: Initial release