2I8E

Structure of SSO1404, a predicted DNA repair-associated protein from Sulfolobus solfataricus P2


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.59 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.188 
  • R-Value Observed: 0.190 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

A novel family of sequence-specific endoribonucleases associated with the clustered regularly interspaced short palindromic repeats.

Beloglazova, N.Brown, G.Zimmerman, M.D.Proudfoot, M.Makarova, K.S.Kudritska, M.Kochinyan, S.Wang, S.Chruszcz, M.Minor, W.Koonin, E.V.Edwards, A.M.Savchenko, A.Yakunin, A.F.

(2008) J Biol Chem 283: 20361-20371

  • DOI: 10.1074/jbc.M803225200
  • Primary Citation of Related Structures:  
    2I8E

  • PubMed Abstract: 
  • Clustered regularly interspaced short palindromic repeats (CRISPRs) together with the associated CAS proteins protect microbial cells from invasion by foreign genetic elements using presently unknown molecular mechanisms. All CRISPR systems contain proteins of the CAS2 family, suggesting that these uncharacterized proteins play a central role in this process ...

    Clustered regularly interspaced short palindromic repeats (CRISPRs) together with the associated CAS proteins protect microbial cells from invasion by foreign genetic elements using presently unknown molecular mechanisms. All CRISPR systems contain proteins of the CAS2 family, suggesting that these uncharacterized proteins play a central role in this process. Here we show that the CAS2 proteins represent a novel family of endoribonucleases. Six purified CAS2 proteins from diverse organisms cleaved single-stranded RNAs preferentially within U-rich regions. A representative CAS2 enzyme, SSO1404 from Sulfolobus solfataricus, cleaved the phosphodiester linkage on the 3'-side and generated 5'-phosphate- and 3'-hydroxyl-terminated oligonucleotides. The crystal structure of SSO1404 was solved at 1.6A resolution revealing the first ribonuclease with a ferredoxin-like fold. Mutagenesis of SSO1404 identified six residues (Tyr-9, Asp-10, Arg-17, Arg-19, Arg-31, and Phe-37) that are important for enzymatic activity and suggested that Asp-10 might be the principal catalytic residue. Thus, CAS2 proteins are sequence-specific endoribonucleases, and we propose that their role in the CRISPR-mediated anti-phage defense might involve degradation of phage or cellular mRNAs.


    Organizational Affiliation

    Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario, Canada.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Hypothetical proteinA101Saccharolobus solfataricus P2Mutation(s): 0 
Gene Names: SSO1404cas21
EC: 3.1
UniProt
Find proteins for Q97YC2 (Saccharolobus solfataricus (strain ATCC 35092 / DSM 1617 / JCM 11322 / P2))
Explore Q97YC2 
Go to UniProtKB:  Q97YC2
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
AL-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.59 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.188 
  • R-Value Observed: 0.190 
  • Space Group: P 62
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 64.277α = 90
b = 64.277β = 90
c = 39.529γ = 120
Software Package:
Software NamePurpose
REFMACrefinement
HKL-3000data collection
HKL-3000data reduction
HKL-3000data scaling
HKL-3000phasing
SHELXDphasing
SHELXEmodel building
MLPHAREphasing
DMphasing
ARP/wARPmodel building
RESOLVEphasing
CCP4phasing
Omodel building
Cootmodel building

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2006-09-26
    Type: Initial release
  • Version 1.1: 2007-10-16
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Advisory, Derived calculations, Source and taxonomy, Version format compliance