3QOE

Crystal Structure of Heterocyst Differentiation Protein, HetR from Fischerella mv11

• PDB DOI: https://doi.org/10.2210/pdb3QOE/pdb

• Classification: DNA BINDING PROTEIN
• Organism(s): Fischerella thermalis PCC 7521
• Expression System: Escherichia coli BL21
• Mutation(s): No 


• Deposited: 2011-02-09 Released: 2011-04-20 
• Deposition Author(s): Kim, Y., Joachimiak, G., Gornicki, P., Joachimiak, A., Midwest Center for Structural Genomics (MCSG)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Free: 0.247 
• R-Value Work: 0.179 
• R-Value Observed: 0.183 

Starting Model: experimental

Literature

Structure of transcription factor HetR required for heterocyst differentiation in cyanobacteria.

Kim, Y., Joachimiak, G., Ye, Z., Binkowski, T.A., Zhang, R., Gornicki, P., Callahan, S.M., Hess, W.R., Haselkorn, R., Joachimiak, A.

(2011) Proc Natl Acad Sci U S A 108: 10109-10114

• PubMed: 21628585 
• DOI: https://doi.org/10.1073/pnas.1106840108
• Primary Citation of Related Structures:  
  3QOD, 3QOE


• PubMed Abstract: 
  

  HetR is an essential regulator of heterocyst development in cyanobacteria. HetR binds to a DNA palindrome upstream of the hetP gene. We report the crystal structure of HetR from Fischerella at 3.0 Å. The protein is a dimer comprised of a central DNA-binding unit containing the N-terminal regions of the two subunits organized with two helix-turn-helix motifs; two globular flaps extending in opposite directions; and a hood over the central core formed from the C-terminal subdomains. The flaps and hood have no structural precedent in the protein database, therefore representing new folds. The structural assignments are supported by site-directed mutagenesis and DNA-binding studies. We suggest that HetR serves as a scaffold for assembly of transcription components critical for heterocyst development.

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Organizational Affiliation: 

Midwest Center for Structural Genomics and Structural Biology Center, Biosciences, Argonne National Laboratory, 9700 South Cass Avenue, Building 202, Argonne, IL 60439, USA.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

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

Macromolecule Content

• Total Structure Weight: 70.47 kDa 
• Atom Count: 4,589 
• Modelled Residue Count: 559 
• Deposited Residue Count: 604 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Heterocyst differentiation protein	A, B	302	Fischerella thermalis PCC 7521	Mutation(s): 0  Gene Names: hetR
UniProt
Find proteins for Q2ACK9 (Fischerella thermalis PCC 7521) Explore Q2ACK9  Go to UniProtKB:  Q2ACK9

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Free: 0.247 
• R-Value Work: 0.179 
• R-Value Observed: 0.183 
• Space Group: P 3₁
• Diffraction Data: https://doi.org/10.18430/M33QOE

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 92.93	α = 90
b = 92.93	β = 90
c = 97.652	γ = 120

Software Package:

Software Name	Purpose
SBC-Collect	data collection
HKL-3000	data collection
HKL-3000	phasing
MOLREP	phasing
PHENIX	refinement
HKL-3000	data reduction
HKL-3000	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2011-04-20 
Deposition Author(s): Kim, Y., Joachimiak, G., Gornicki, P., Joachimiak, A., Midwest Center for Structural Genomics (MCSG)

Revision History  

• Version 1.0: 2011-04-20
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance
• Version 1.2: 2023-09-13
  Changes: Data collection, Database references, Refinement description