4IWB

Novel Fold of FliC/FliS Fusion Protein

• PDB DOI: https://doi.org/10.2210/pdb4IWB/pdb

• Classification: MOTOR PROTEIN
• Organism(s): Aquifex aeolicus
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2013-01-23 Released: 2013-12-11 
• Deposition Author(s): Faham, S.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.75 Å
• R-Value Free: 0.232 
• R-Value Work: 0.209 
• R-Value Observed: 0.210 

Literature

Protein design by fusion: implications for protein structure prediction and evolution.

Skorupka, K., Han, S.K., Nam, H.J., Kim, S., Faham, S.

(2013) Acta Crystallogr D Biol Crystallogr 69: 2451-2460

• PubMed: 24311586 
• DOI: https://doi.org/10.1107/S0907444913022701
• Primary Citation of Related Structures:  
  4IWB


• PubMed Abstract: 
  

  Domain fusion is a useful tool in protein design. Here, the structure of a fusion of the heterodimeric flagella-assembly proteins FliS and FliC is reported. Although the ability of the fusion protein to maintain the structure of the heterodimer may be apparent, threading-based structural predictions do not properly fuse the heterodimer. Additional examples of naturally occurring heterodimers that are homologous to full-length proteins were identified. These examples highlight that the designed protein was engineered by the same tools as used in the natural evolution of proteins and that heterodimeric structures contain a wealth of information, currently unused, that can improve structural predictions.

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Organizational Affiliation: 

Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA 22093, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Biological Assembly 2  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 assigned by authors.

Macromolecule Content

• Total Structure Weight: 38.58 kDa 
• Atom Count: 2,823 
• Modelled Residue Count: 321 
• Deposited Residue Count: 330 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
FliC, FliS chimera	A, B	165	Aquifex aeolicus	Mutation(s): 0  Gene Names: aq_1998, flaA, fliC, fliS
UniProt
Find proteins for O67803 (Aquifex aeolicus (strain VF5)) Explore O67803  Go to UniProtKB:  O67803
Find proteins for O67806 (Aquifex aeolicus (strain VF5)) Explore O67806  Go to UniProtKB:  O67806
UniProt Groups	O67803O67806

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.75 Å
• R-Value Free: 0.232 
• R-Value Work: 0.209 
• R-Value Observed: 0.210 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 61.129	α = 90
b = 66.157	β = 90
c = 97.169	γ = 90

Software Package:

Software Name	Purpose
HKL-2000	data collection
PHASER	phasing
REFMAC	refinement
HKL-2000	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2013-12-11 
Deposition Author(s): Faham, S.

Revision History  

• Version 1.0: 2013-12-11
  Type: Initial release
  
• Version 1.1: 2014-02-05
  Changes: Database references
• Version 1.2: 2017-07-26
  Changes: Refinement description, Source and taxonomy
• Version 1.3: 2024-02-28
  Changes: Data collection, Database references