2KC8

Structure of E. coli toxin RelE (R81A/R83A) mutant in complex with antitoxin RelBc (K47-L79) peptide

2KC8 の概要

• エントリーDOI: 10.2210/pdb2kc8/pdb
• 関連するPDBエントリー: 2KC9
• NMR情報: BMRB: 16065
• 分子名称: Toxin relE, Antitoxin RelB (2 entities in total)
• 機能のキーワード: protein-protein complex, toxin rele, antitoxin relb, repressor, stress response, toxin, transcription, transcription regulation, toxin-toxin repressor complex, toxin/toxin repressor
• 由来する生物種: Escherichia coli; 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 15491.99

構造登録者

Li, G.,Zhang, Y.,Inouye, M.,Ikura, M. (登録日: 2008-12-17, 公開日: 2009-03-17, 最終更新日: 2024-05-22)

主引用文献

Li, G.Y.,Zhang, Y.,Inouye, M.,Ikura, M.
Inhibitory mechanism of Escherichia coli RelE-RelB toxin-antitoxin module involves a helix displacement near an mRNA interferase active site.
J.Biol.Chem., 284:14628-14636, 2009

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.

PubMed: 19297318
DOI: 10.1074/jbc.M809656200

実験手法

SOLUTION NMR