7TF6

S. aureus GS(12)-Q-GlnR peptide

これはPDB形式変換不可エントリーです。

7TF6 の概要

• エントリーDOI: 10.2210/pdb7tf6/pdb
• EMDBエントリー: 25863
• 分子名称: Glutamine synthetase, Peptide from Glutamine synthetase repressor, MAGNESIUM ION, ... (4 entities in total)
• 機能のキーワード: glutamine synthetase repressor dodecamer, biosynthetic protein, ligase
• 由来する生物種: Staphylococcus aureus; 詳細
• タンパク質・核酸の鎖数: 24
• 化学式量合計: 632172.95

構造登録者

Travis, B.A.,Peck, J.,Schumacher, M.A. (登録日: 2022-01-06, 公開日: 2022-06-29, 最終更新日: 2024-02-28)

主引用文献

Travis, B.A.,Peck, J.V.,Salinas, R.,Dopkins, B.,Lent, N.,Nguyen, V.D.,Borgnia, M.J.,Brennan, R.G.,Schumacher, M.A.
Molecular dissection of the glutamine synthetase-GlnR nitrogen regulatory circuitry in Gram-positive bacteria.
Nat Commun, 13:3793-3793, 2022

PubMed Abstract: How bacteria sense and respond to nitrogen levels are central questions in microbial physiology. In Gram-positive bacteria, nitrogen homeostasis is controlled by an operon encoding glutamine synthetase (GS), a dodecameric machine that assimilates ammonium into glutamine, and the GlnR repressor. GlnR detects nitrogen excess indirectly by binding glutamine-feedback-inhibited-GS (FBI-GS), which activates its transcription-repression function. The molecular mechanisms behind this regulatory circuitry, however, are unknown. Here we describe biochemical and structural analyses of GS and FBI-GS-GlnR complexes from pathogenic and non-pathogenic Gram-positive bacteria. The structures show FBI-GS binds the GlnR C-terminal domain within its active-site cavity, juxtaposing two GlnR monomers to form a DNA-binding-competent GlnR dimer. The FBI-GS-GlnR interaction stabilizes the inactive GS conformation. Strikingly, this interaction also favors a remarkable dodecamer to tetradecamer transition in some GS, breaking the paradigm that all bacterial GS are dodecamers. These data thus unveil unique structural mechanisms of transcription and enzymatic regulation.

PubMed: 35778410
DOI: 10.1038/s41467-022-31573-0

実験手法

ELECTRON MICROSCOPY (2.15 Å)