3F2W

Crystal structure of the FMn riboswitch bound to FMN, Ba2+ soak.

  • Classification: RNA
  • Mutation(s): No 

  • Deposited: 2008-10-30 Released: 2009-01-27 
  • Deposition Author(s): Serganov, A.A., Huang, L.

Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.45 Å
  • R-Value Free: 0.217 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.182 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history. 


Literature

Coenzyme recognition and gene regulation by a flavin mononucleotide riboswitch.

Serganov, A., Huang, L., Patel, D.J.

(2009) Nature 458: 233-237

  • DOI: 10.1038/nature07642
  • Structures With Same Primary Citation

  • 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 tran ...

    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.

    Organizational Affiliation: 

    Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA. serganoa@mskcc.org



Macromolecules

Find similar nucleic acids by: Sequence   |  Structure

Entity ID: 1
MoleculeChainsLengthOrganism
FMN riboswitchX112N/A
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
FMN
Query on FMN
Download CCD File 
X
FLAVIN MONONUCLEOTIDE
C17 H21 N4 O9 P
FVTCRASFADXXNN-SCRDCRAPSA-N		 Ligand Interaction
BA
Query on BA
Download CCD File 
X
BARIUM ION
Ba
XDFCIPNJCBUZJN-UHFFFAOYSA-N		 Ligand Interaction
MG
Query on MG
Download CCD File 
X
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N		 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.45 Å
  • R-Value Free: 0.217 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.182 
  • Space Group: P 31 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 71.003α = 90
b = 71.003β = 90
c = 139.745γ = 120
Software Package:
Software NamePurpose
CBASSdata collection
MOLREPphasing
REFMACrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

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View more in-depth experimental data

Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-01-27
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Refinement description, Version format compliance