5CQX

E. coli MazF mutant E24A in complex with MazE residues 68-82 form I

5CQX の概要

• エントリーDOI: 10.2210/pdb5cqx/pdb
• 分子名称: Endoribonuclease MazF, Antitoxin MazE (3 entities in total)
• 機能のキーワード: toxin-antitoxin, mrna interferase, ribonuclease, persistence, bacterial stress response, hydrolase
• 由来する生物種: Escherichia coli K-12; 詳細
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 28051.22

構造登録者

Zorzini, V.,Loris, R. (登録日: 2015-07-22, 公開日: 2016-04-06, 最終更新日: 2024-10-23)

主引用文献

Zorzini, V.,Mernik, A.,Lah, J.,Sterckx, Y.G.,De Jonge, N.,Garcia-Pino, A.,De Greve, H.,Versees, W.,Loris, R.
Substrate Recognition and Activity Regulation of the Escherichia coli mRNA Endonuclease MazF.
J.Biol.Chem., 291:10950-10960, 2016

PubMed Abstract: Escherichia coli MazF (EcMazF) is the archetype of a large family of ribonucleases involved in bacterial stress response. The crystal structure of EcMazF in complex with a 7-nucleotide substrate mimic explains the relaxed substrate specificity of the E. coli enzyme relative to its Bacillus subtilis counterpart and provides a framework for rationalizing specificity in this enzyme family. In contrast to a conserved mode of substrate recognition and a conserved active site, regulation of enzymatic activity by the antitoxin EcMazE diverges from its B. subtilis homolog. Central in this regulation is an EcMazE-induced double conformational change as follows: a rearrangement of a crucial active site loop and a relative rotation of the two monomers in the EcMazF dimer. Both are induced by the C-terminal residues Asp-78-Trp-82 of EcMazE, which are also responsible for strong negative cooperativity in EcMazE-EcMazF binding. This situation shows unexpected parallels to the regulation of the F-plasmid CcdB activity by CcdA and further supports a common ancestor despite the different activities of the MazF and CcdB toxins. In addition, we pinpoint the origin of the lack of activity of the E24A point mutant of EcMazF in its inability to support the substrate binding-competent conformation of EcMazF.

PubMed: 27026704
DOI: 10.1074/jbc.M116.715912

実験手法

X-RAY DIFFRACTION (1.63 Å)