Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | Ligand Interaction

Global Symmetry: Cyclic - C6  (3D View)
Global Stoichiometry: Homo 6-mer - A6 

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

Biological Assembly 2  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | Ligand Interaction

Global Symmetry: Cyclic - C6  (3D View)
Global Stoichiometry: Homo 6-mer - A6 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 105.74 kDa 
• Atom Count: 6611 
• Modelled Residue Count: 734 
• Deposited Residue Count: 924 
• Unique protein chains: 1

1KQ1

1.55 A Crystal structure of the pleiotropic translational regulator, Hfq

• PDB DOI: 10.2210/pdb1KQ1/pdb

• Classification: TRANSLATION
• Organism(s): Staphylococcus aureus
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2002-01-03 Released: 2002-07-10 
• Deposition Author(s): Schumacher, M.A., Pearson, R.F., Moller, T., Valentin-Hansen, P., Brennan, R.G.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.55 Å
• R-Value Free: 0.259 
• R-Value Work: 0.237 

Literature

Structures of the pleiotropic translational regulator Hfq and an Hfq-RNA complex: a bacterial Sm-like protein.

Schumacher, M.A., Pearson, R.F., Moller, T., Valentin-Hansen, P., Brennan, R.G.

(2002) EMBO J 21: 3546-3556

• PubMed: 12093755 
• DOI: 10.1093/emboj/cdf322
• Primary Citation of Related Structures:  
  1KQ1, 1KQ2


• PubMed Abstract: 
  

In prokaryotes, Hfq regulates translation by modulating the structure of numerous RNA molecules by binding preferentially to A/U-rich sequences. To elucidate the mechanisms of target recognition and translation regulation by Hfq, we determined the crystal structures of the Staphylococcus aureus Hfq and an Hfq-RNA complex to 1.55 and 2.71 A resolution, respectively. The structures reveal that Hfq possesses the Sm-fold previously observed only in eukaryotes and archaea. However, unlike these heptameric Sm proteins, Hfq forms a homo-hexameric ring. The Hfq-RNA structure reveals that the single-stranded hepta-oligoribonucleotide binds in a circular conformation around a central basic cleft, whereby Tyr42 residues from adjacent subunits stack with six of the bases, and Gln8, outside the Sm motif, provides key protein-base contacts. Such binding suggests a mechanism for Hfq function.

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Organizational Affiliation: 

Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, OR 97201-3098, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Host Factor for Q beta	A, B, C [auth H], D [auth I], E [auth K], F [auth M], J [auth N], K [auth R], G [auth S], H [auth T], L [auth W], I [auth Y]	77	Staphylococcus aureus	Mutation(s): 0
UniProt
Find proteins for A0A0H3JV59 (Staphylococcus aureus (strain Mu50 / ATCC 700699)) Explore A0A0H3JV59  Go to UniProtKB:  A0A0H3JV59

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ACY	M [auth A], N [auth A], O [auth H], P [auth T], Q [auth R]	ACETIC ACID C2 H4 O2 QTBSBXVTEAMEQO-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.55 Å
• R-Value Free: 0.259 
• R-Value Work: 0.237 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 67.03	α = 90
b = 89.95	β = 97.95
c = 67.77	γ = 90

Software Package:

Software Name	Purpose
PHASES	phasing
CNS	refinement
MOSFLM	data reduction
CCP4	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2002-01-03 
• Released Date: 2002-07-10 
Deposition Author(s): Schumacher, M.A., Pearson, R.F., Moller, T., Valentin-Hansen, P., Brennan, R.G.

Revision History  

• Version 1.0: 2002-07-10
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance