Biological Assembly 1  

 3D View: Structure | 1D-3D View | Validation Report

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 11.36 kDa 
• Atom Count: 778 
• Modelled Residue Count: 95 
• Deposited Residue Count: 98 
• Unique protein chains: 1

2KC9

Structure of E. coli toxin RelE (R81A/R83A) mutant in the free state

• PDB DOI: 10.2210/pdb2KC9/pdb
• BMRB: 16066

• Classification: TOXIN
• Organism(s): Escherichia coli K-12
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2008-12-17 Released: 2009-03-17 
• Deposition Author(s): Li, G., Zhang, Y., Inouye, M., Ikura, M.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 

Literature

Inhibitory mechanism of Escherichia coli RelE-RelB toxin-antitoxin module involves a helix displacement near an mRNA interferase active site.

Li, G.Y., Zhang, Y., Inouye, M., Ikura, M.

(2009) J Biol Chem 284: 14628-14636

• PubMed: 19297318 
• DOI: 10.1074/jbc.M809656200
• Primary Citation of Related Structures:  
  2KC8, 2KC9


• PubMed Abstract: 
  

In Escherichia coli, RelE toxin participates in growth arrest and cell death by inducing mRNA degradation at the ribosomal A-site under stress conditions. The NMR structures of a mutant of E. coli RelE toxin, RelE(R81A/R83A), with reduced toxicity and its complex with an inhibitory peptide from RelB antitoxin, RelB(C) (Lys(47)-Leu(79)), have been determined. In the free RelE(R81A/R83A) structure, helix alpha4 at the C terminus adopts a closed conformation contacting with the beta-sheet core and adjacent loops. In the RelE(R81A/R83A)-RelB(C) complex, helix alpha3(*) of RelB(C) displaces alpha4 of RelE(R81A/R83A) from the binding site on the beta-sheet core. This helix replacement results in neutralization of a conserved positively charged cluster of RelE by acidic residues from alpha3(*) of RelB. The released helix alpha4 becomes unfolded, adopting an open conformation with increased mobility. The displacement of alpha4 disrupts the geometry of critical residues, including Arg(81) and Tyr(87), in a putative active site of RelE toxin. Our structures indicate that RelB counteracts the toxic activity of RelE by displacing alpha4 helix from the catalytically competent position found in the free RelE structure.

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Organizational Affiliation: 

Division of Signaling Biology, Ontario Cancer Institute, Toronto, Ontario, Canada.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Toxin relE	A	98	Escherichia coli K-12	Mutation(s): 2  Gene Names: relE, b1563, JW1555 EC: 3.1
UniProt
Find proteins for P0C077 (Escherichia coli (strain K12)) Explore P0C077  Go to UniProtKB:  P0C077

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 
• OLDERADO: 2KC9 Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2008-12-17 
• Released Date: 2009-03-17 
Deposition Author(s): Li, G., Zhang, Y., Inouye, M., Ikura, M.

Revision History  

• Version 1.0: 2009-03-17
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance
• Version 1.2: 2021-10-20
  Changes: Data collection, Database references, Derived calculations