Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 11-mer - A5B2CDEF Pseudo Symmetry: Asymmetric - C1 
Pseudo Stoichiometry: Hetero 11-mer -A6B2CDE 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 413400.25 
• Atom Count: 26543 
• Residue Count: 3524 
• Unique protein chains: 5
• Unique nucleic acid chains: 2

4QYZ

Crystal structure of a CRISPR RNA-guided surveillance complex, Cascade, bound to a ssDNA target

• DOI: 10.2210/pdb4QYZ/pdb
• NDB: NA3085

• Classification: IMMUNE SYSTEM/DNA/RNA
• Organism(s): Escherichia coli (strain K12), Escherichia virus Lambda, Escherichia coli
• Expression System: Escherichia coli


• Deposited: 2014-07-26 Released: 2014-09-03 
• Deposition Author(s): Mulepati, S., Bailey, S.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.0303 Å
• R-Value Free: 0.267 
• R-Value Work: 0.224 

Literature

Structural biology. Crystal structure of a CRISPR RNA-guided surveillance complex bound to a ssDNA target.

Mulepati, S., Heroux, A., Bailey, S.

(2014) Science 345: 1479-1484

• PubMed: 25123481 
• DOI: 10.1126/science.1256996


• PubMed Abstract: 
  

In prokaryotes, RNA derived from type I and type III CRISPR loci direct large ribonucleoprotein complexes to destroy invading bacteriophage and plasmids. In Escherichia coli, this 405-kilodalton complex is called Cascade. We report the crystal structure of Cascade bound to a single-stranded DNA (ssDNA) target at a resolution of 3.03 angstroms. The structure reveals that the CRISPR RNA and target strands do not form a double helix but instead adopt an underwound ribbon-like structure. This noncanonical structure is facilitated by rotation of every sixth nucleotide out of the RNA-DNA hybrid and is stabilized by the highly interlocked organization of protein subunits. These studies provide insight into both the assembly and the activity of this complex and suggest a mechanism to enforce fidelity of target binding.

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Organizational Affiliation: 

Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
CRISPR system Cascade subunit CasA	A	502	Escherichia coli (strain K12)	Mutation(s): 0  Gene Names: casA (cse1, ygcL)
Find proteins for Q46901 (Escherichia coli (strain K12)) Go to UniProtKB:  Q46901

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
CRISPR system Cascade subunit CasB	B, C	160	Escherichia coli (strain K12)	Mutation(s): 0  Gene Names: casB (cse2, ygcK)
Find proteins for P76632 (Escherichia coli (strain K12)) Go to UniProtKB:  P76632

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details
CRISPR system Cascade subunit CasC	D, E, F, G, H, I	363	Escherichia coli (strain K12)	Mutation(s): 0  Gene Names: casC (cas4, cse4, ygcJ)
Find proteins for Q46899 (Escherichia coli (strain K12)) Go to UniProtKB:  Q46899

Entity ID: 4
Molecule	Chains	Sequence Length	Organism	Details
CRISPR system Cascade subunit CasD	J	224	Escherichia coli (strain K12)	Mutation(s): 0  Gene Names: casD (cas5, ygcI)
Find proteins for Q46898 (Escherichia coli (strain K12)) Go to UniProtKB:  Q46898

Entity ID: 5
Molecule	Chains	Sequence Length	Organism	Details
CRISPR system Cascade subunit CasE	K	199	Escherichia coli (strain K12)	Mutation(s): 0  Gene Names: casE (cas6e, ygcH) EC: 3.1.-.-
Find proteins for Q46897 (Escherichia coli (strain K12)) Go to UniProtKB:  Q46897

Entity ID: 6
Molecule	Chains	Length	Organism
RNA (55-MER)	L	61	Escherichia coli

Entity ID: 7
Molecule	Chains	Length	Organism
DNA (33-MER)	M	40	Escherichia virus Lambda

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
ZN	A	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.0303 Å
• R-Value Free: 0.267 
• R-Value Work: 0.224 
• Space Group: P 3₁ 2 1

Unit Cell:

Length (Å)	Angle (°)
a = 223.869	α = 90.00
b = 223.869	β = 90.00
c = 290.651	γ = 120.00

Software Package:

Software Name	Purpose
PHENIX	refinement
Aimless	data scaling
Blu-Ice	data collection
SOLVE	phasing
XDS	data reduction

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2014-07-26 
• Released Date: 2014-09-03 
• Deposition Author(s): Mulepati, S., Bailey, S.

Revision History 

• Version 1.0: 2014-09-03
  Type: Initial release
• Version 1.1: 2014-10-01
  Type: Database references