1QTG

AVERAGED NMR MODEL OF SWITCH ARC, A DOUBLE MUTANT OF ARC REPRESSOR

• PDB DOI: https://doi.org/10.2210/pdb1QTG/pdb
• BMRB: 4540

• Classification: GENE REGULATION
• Organism(s): Lederbergvirus P22
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 1999-06-27 Released: 1999-07-12 
• Deposition Author(s): Cordes, M.H.J., Walsh, N.P., McKnight, C.J., Sauer, R.T.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Submitted: 1 

Literature

Evolution of a protein fold in vitro.

Cordes, M.H., Walsh, N.P., McKnight, C.J., Sauer, R.T.

(1999) Science 284: 325-327

• PubMed: 10195898 
• DOI: https://doi.org/10.1126/science.284.5412.325
• Primary Citation of Related Structures:  
  1QTG


• PubMed Abstract: 
  

  A "switch" mutant of the Arc repressor homodimer was constructed by interchanging the sequence positions of a hydrophobic core residue, leucine 12, and an adjacent surface polar residue, asparagine 11, in each strand of an intersubunit beta sheet. The mutant protein adopts a fold in which each beta strand is replaced by a right-handed helix and side chains in this region undergo significant repacking. The observed structural changes allow the protein to maintain solvent exposure of polar side chains and optimal burial of hydrophobic side chains. These results suggest that new protein folds can evolve from existing folds without drastic or large-scale mutagenesis.

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Organizational Affiliation: 

Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 12.48 kDa 
• Atom Count: 870 
• Modelled Residue Count: 106 
• Deposited Residue Count: 106 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Transcriptional repressor arc	A, B	53	Lederbergvirus P22	Mutation(s): 2  Gene Names: arc
UniProt
Find proteins for P03050 (Salmonella phage P22) Explore P03050  Go to UniProtKB:  P03050

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Submitted: 1 

Structure Validation

Currently 1QTG does not have a validation slider image.

Entry History 

Deposition Data

• Released Date: 1999-07-12 
Deposition Author(s): Cordes, M.H.J., Walsh, N.P., McKnight, C.J., Sauer, R.T.

Revision History  

• Version 1.0: 1999-07-12
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2022-03-02
  Changes: Database references, Derived calculations
• Version 1.4: 2022-12-21
  Changes: Database references, Source and taxonomy, Structure summary