6AS4

Structure of a phage anti-CRISPR protein


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.190 
  • R-Value Observed: 0.192 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Disabling a Type I-E CRISPR-Cas Nuclease with a Bacteriophage-Encoded Anti-CRISPR Protein.

Pawluk, A.Shah, M.Mejdani, M.Calmettes, C.Moraes, T.F.Davidson, A.R.Maxwell, K.L.

(2017) mBio 8

  • DOI: 10.1128/mBio.01751-17
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • CRISPR (clustered regularly interspaced short palindromic repeat)-Cas adaptive immune systems are prevalent defense mechanisms in bacteria and archaea. They provide sequence-specific detection and neutralization of foreign nucleic acids such as bacte ...

    CRISPR (clustered regularly interspaced short palindromic repeat)-Cas adaptive immune systems are prevalent defense mechanisms in bacteria and archaea. They provide sequence-specific detection and neutralization of foreign nucleic acids such as bacteriophages and plasmids. One mechanism by which phages and other mobile genetic elements are able to overcome the CRISPR-Cas system is through the expression of anti-CRISPR proteins. Over 20 different families of anti-CRISPR proteins have been described, each of which inhibits a particular type of CRISPR-Cas system. In this work, we determined the structure of type I-E anti-CRISPR protein AcrE1 by X-ray crystallography. We show that AcrE1 binds to the CRISPR-associated helicase/nuclease Cas3 and that the C-terminal region of the anti-CRISPR protein is important for its inhibitory activity. We further show that AcrE1 can convert the endogenous type I-E CRISPR system into a programmable transcriptional repressor. IMPORTANCE The CRISPR-Cas immune system provides bacteria with resistance to invasion by potentially harmful viruses, plasmids, and other foreign mobile genetic elements. This study presents the first structural and mechanistic insight into a phage-encoded protein that inactivates the type I-E CRISPR-Cas system in Pseudomonas aeruginosa The interaction of this anti-CRISPR protein with the CRISPR-associated helicase/nuclease proteins Cas3 shuts down the CRISPR-Cas system and protects phages carrying this gene from destruction. This interaction also allows the repurposing of the endogenous type I-E CRISPR system into a programmable transcriptional repressor, providing a new biotechnological tool for genetic studies of bacteria encoding this type I-E CRISPR-Cas system.


    Organizational Affiliation

    Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada alan.davidson@utoronto.ca karen.maxwell@utoronto.ca.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
NHis AcrE1 anti-crispr proteinA, B, C106Pseudomonas phage JBD5Mutation(s): 0 
Gene Names: JBD5_034
Find proteins for L7P7L6 (Pseudomonas phage JBD5)
Explore L7P7L6 
Go to UniProtKB:  L7P7L6
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.190 
  • R-Value Observed: 0.192 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 96.74α = 90
b = 63.53β = 100.34
c = 59.46γ = 90
Software Package:
Software NamePurpose
XSCALEdata scaling
PHENIXrefinement
PDB_EXTRACTdata extraction
XDSdata processing
PHASERphasing

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Canadian Institutes of Health Research (CIHR)CanadaMOP-130482
Canadian Institutes of Health Research (CIHR)CanadaMOP-136845

Revision History 

  • Version 1.0: 2017-12-20
    Type: Initial release
  • Version 1.1: 2017-12-27
    Changes: Database references
  • Version 1.2: 2020-01-08
    Changes: Author supporting evidence