7ETR

Crystal structure of SO_1444-SO_1445 complex from Shewanella oneidensis

7ETR の概要

• エントリーDOI: 10.2210/pdb7etr/pdb
• 分子名称: Transcriptional regulator CopG family, Toxin module of toxin-antitoxin system RelE/StbE family (2 entities in total)
• 機能のキーワード: toxin-antitoxin, pare toxin, neutralization mechanism, toxin
• 由来する生物種: Shewanella oneidensis MR-1; 詳細
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 46428.72

構造登録者

Zhou, J.,Zhang, H. (登録日: 2021-05-13, 公開日: 2022-03-23)

主引用文献

Zhou, J.,Du, X.J.,Liu, Y.,Gao, Z.Q.,Geng, Z.,Dong, Y.H.,Zhang, H.
Insights into the Neutralization and DNA Binding of Toxin-Antitoxin System ParE SO-CopA SO by Structure-Function Studies.
Microorganisms, 9:-, 2021

PubMed Abstract: ParE-CopA is a new type II toxin-antitoxin (TA) system in prophage CP4So that plays an essential role in circular CP4So maintenance after the excision in . The toxin ParE severely inhibits cell growth, while CopA functions as an antitoxin to neutralize ParE toxicity through direct interactions. However, the molecular mechanism of the neutralization and autoregulation of the TA operon transcription remains elusive. In this study, we determined the crystal structure of a ParE-CopA complex that adopted an open V-shaped heterotetramer with the organization of ParE-(CopA)-ParE. The structure showed that upon ParE binding, the intrinsically disordered C-terminal domain of CopA was induced to fold into a partially ordered conformation that bound into a positively charged and hydrophobic groove of ParE. Thermodynamics analysis showed the DNA-binding affinity of CopA was remarkably higher than that of the purified TA complex, accompanied by the enthalpy change reversion from an exothermic reaction to an endothermic reaction. These results suggested ParE acts as a de-repressor of the TA operon transcription at the toxin:antitoxin level of 1:1. Site-directed mutagenesis of ParE identified His91 as the essential residue for its toxicity by cell toxicity assays. Our structure-function studies therefore elucidated the transcriptional regulation mechanism of the ParE-CopA pair, and may help to understand the regulation of CP4So maintenance in .

PubMed: 34946107
DOI: 10.3390/microorganisms9122506

実験手法

X-RAY DIFFRACTION (3.804 Å)