3ZC4

The structure of Csa5 from Sulfolobus solfataricus.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.72 Å
  • R-Value Free: 0.217 
  • R-Value Work: 0.205 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of the Archaeal Cascade Subunit Csa5: Relating the Small Subunits of Crispr Effector Complexes.

Reeks, J.Graham, S.Anderson, L.Liu, H.White, M.F.Naismith, J.H.

(2013) RNA Biol. 10: 762

  • DOI: 10.4161/rna.23854

  • PubMed Abstract: 
  • The Cascade complex for CRISPR-mediated antiviral immunity uses CRISPR RNA (crRNA) to target invading DNA species from mobile elements such as viruses, leading to their destruction. The core of the Cascade effector complex consists of the Cas5 and Ca ...

    The Cascade complex for CRISPR-mediated antiviral immunity uses CRISPR RNA (crRNA) to target invading DNA species from mobile elements such as viruses, leading to their destruction. The core of the Cascade effector complex consists of the Cas5 and Cas7 subunits, which are widely conserved in prokaryotes. Cas7 binds crRNA and forms the helical backbone of Cascade. Many archaea encode a version of the Cascade complex (denoted Type I-A) that includes a Csa5 (or small) subunit, which interacts weakly with the core proteins. Here, we report the crystal structure of the Csa5 protein from Sulfolobus solfataricus. Csa5 comprises a conserved α-helical domain with a small insertion consisting of a weakly conserved β-strand domain. In the crystal, the Csa5 monomers have multimerized into infinite helical threads. At each interface is a strictly conserved intersubunit salt bridge, deletion of which disrupts multimerization. Structural analysis indicates a shared evolutionary history among the small subunits of the CRISPR effector complexes. The same α-helical domain is found in the C-terminal domain of Cse2 (from Type I-E Cascade), while the N-terminal domain of Cse2 is found in Cmr5 of the CMR (Type III-B) effector complex. As Cmr5 shares no match with Csa5, two possibilities present themselves: selective domain loss from an ancestral Cse2 to create two new subfamilies or domain fusion of two separate families to create a new Cse2 family. A definitive answer awaits structural studies of further small subunits from other CRISPR effector complexes.


    Organizational Affiliation

    Biomedical Sciences Research Complex, University of St. Andrews, North Haugh, St. Andrews, Fife, UK.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
SSO1398
A, B, C, D, E, F, G, H, I
164Saccharolobus solfataricus (strain ATCC 35092 / DSM 1617 / JCM 11322 / P2)Mutation(s): 0 
Gene Names: csa5
Find proteins for Q97YC8 (Saccharolobus solfataricus (strain ATCC 35092 / DSM 1617 / JCM 11322 / P2))
Go to UniProtKB:  Q97YC8
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PEG
Query on PEG

Download SDF File 
Download CCD File 
C, D, E, F, G, H, I
DI(HYDROXYETHYL)ETHER
C4 H10 O3
MTHSVFCYNBDYFN-UHFFFAOYSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A, B, C, D, E, F, G, H, I
L-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.72 Å
  • R-Value Free: 0.217 
  • R-Value Work: 0.205 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 285.000α = 90.00
b = 53.720β = 124.65
c = 216.680γ = 90.00
Software Package:
Software NamePurpose
xia2data reduction
REFMACrefinement
PHENIXphasing
xia2data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-02-20
    Type: Initial release
  • Version 1.1: 2013-07-24
    Type: Database references
  • Version 1.2: 2013-07-31
    Type: Atomic model, Database references