3F2X

Crystal structure of the FMN riboswitch bound to FMN, Cs+ soak.

3F2X の概要

• エントリーDOI: 10.2210/pdb3f2x/pdb
• 関連するPDBエントリー: 3F2Q 3F2T 3F2W 3F2Y 3F30 3F4E 3F4G 3F4H
• 分子名称: FMN riboswitch, FLAVIN MONONUCLEOTIDE, MAGNESIUM ION, ... (5 entities in total)
• 機能のキーワード: fmn, riboswitch, transcription, cesium, rna
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 37755.35

構造登録者

Serganov, A.A.,Huang, L. (登録日: 2008-10-30, 公開日: 2009-01-27, 最終更新日: 2023-09-06)

主引用文献

Serganov, A.,Huang, L.,Patel, D.J.
Coenzyme recognition and gene regulation by a flavin mononucleotide riboswitch.
Nature, 458:233-237, 2009

PubMed Abstract: The biosynthesis of several protein cofactors is subject to feedback regulation by riboswitches. Flavin mononucleotide (FMN)-specific riboswitches, also known as RFN elements, direct expression of bacterial genes involved in the biosynthesis and transport of riboflavin (vitamin B(2)) and related compounds. Here we present the crystal structures of the Fusobacterium nucleatum riboswitch bound to FMN, riboflavin and antibiotic roseoflavin. The FMN riboswitch structure, centred on an FMN-bound six-stem junction, does not fold by collinear stacking of adjacent helices, typical for folding of large RNAs. Rather, it adopts a butterfly-like scaffold, stapled together by opposingly directed but nearly identically folded peripheral domains. FMN is positioned asymmetrically within the junctional site and is specifically bound to RNA through interactions with the isoalloxazine ring chromophore and direct and Mg(2+)-mediated contacts with the phosphate moiety. Our structural data, complemented by binding and footprinting experiments, imply a largely pre-folded tertiary RNA architecture and FMN recognition mediated by conformational transitions within the junctional binding pocket. The inherent plasticity of the FMN-binding pocket and the availability of large openings make the riboswitch an attractive target for structure-based design of FMN-like antimicrobial compounds. Our studies also explain the effects of spontaneous and antibiotic-induced deregulatory mutations and provided molecular insights into FMN-based control of gene expression in normal and riboflavin-overproducing bacterial strains.

PubMed: 19169240
DOI: 10.1038/nature07642

実験手法

X-RAY DIFFRACTION (3.11 Å)