4MCT

P. vulgaris HIGBA structure, crystal form 1

4MCT の概要

• エントリーDOI: 10.2210/pdb4mct/pdb
• 関連するPDBエントリー: 4MCX
• 分子名称: Antidote protein, Killer protein (3 entities in total)
• 機能のキーワード: bacterial toxins, biofilms, cell metabolism, energy metabolism, helix-turn-helix transcription factors, microbial pathogenesis, stress response, stringent response, transcription repressor, translation control, toxin
• 由来する生物種: Proteus vulgaris; 詳細
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 50004.62

構造登録者

Schureck, M.A.,Maehigashi, T.,Dunham, C.M. (登録日: 2013-08-21, 公開日: 2013-12-11, 最終更新日: 2024-10-09)

主引用文献

Schureck, M.A.,Maehigashi, T.,Miles, S.J.,Marquez, J.,Cho, S.E.,Erdman, R.,Dunham, C.M.
Structure of the Proteus vulgaris HigB-(HigA)2-HigB Toxin-Antitoxin Complex.
J.Biol.Chem., 289:1060-1070, 2014

PubMed Abstract: Bacterial toxin-antitoxin (TA) systems regulate key cellular processes to promote cell survival during periods of stress. During steady-state cell growth, antitoxins typically interact with their cognate toxins to inhibit activity presumably by preventing substrate recognition. We solved two x-ray crystal structures of the Proteus vulgaris tetrameric HigB-(HigA)2-HigB TA complex and found that, unlike most other TA systems, the antitoxin HigA makes minimal interactions with toxin HigB. HigB adopts a RelE family tertiary fold containing a highly conserved concave surface where we predict its active site is located. HigA does not cover the solvent-exposed HigB active site, suggesting that, in general, toxin inhibition is not solely mediated by active site hindrance by its antitoxin. Each HigA monomer contains a helix-turn-helix motif that binds to its own DNA operator to repress transcription during normal cellular growth. This is distinct from antitoxins belonging to other superfamilies that typically only form DNA-binding motifs upon dimerization. We further show that disruption of the HigB-(HigA)2-HigB tetramer to a HigBA heterodimer ablates operator binding. Taken together, our biochemical and structural studies elucidate the novel molecular details of the HigBA TA system.

PubMed: 24257752
DOI: 10.1074/jbc.M113.512095

実験手法

X-RAY DIFFRACTION (2.8 Å)