2DER

Cocrystal structure of an RNA sulfuration enzyme MnmA and tRNA-Glu in the initial tRNA binding state


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.1 Å
  • R-Value Free: 0.269 
  • R-Value Work: 0.219 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Snapshots of tRNA sulphuration via an adenylated intermediate

Numata, T.Ikeuchi, Y.Fukai, S.Suzuki, T.Nureki, O.

(2006) Nature 442: 419-424

  • DOI: 10.1038/nature04896
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Uridine at the first anticodon position (U34) of glutamate, lysine and glutamine transfer RNAs is universally modified by thiouridylase into 2-thiouridine (s2U34), which is crucial for precise translation by restricting codon-anticodon wobble during ...

    Uridine at the first anticodon position (U34) of glutamate, lysine and glutamine transfer RNAs is universally modified by thiouridylase into 2-thiouridine (s2U34), which is crucial for precise translation by restricting codon-anticodon wobble during protein synthesis on the ribosome. However, it remains unclear how the enzyme incorporates reactive sulphur into the correct position of the uridine base. Here we present the crystal structures of the MnmA thiouridylase-tRNA complex in three discrete forms, which provide snapshots of the sequential chemical reactions during RNA sulphuration. On enzyme activation, an alpha-helix overhanging the active site is restructured into an idiosyncratic beta-hairpin-containing loop, which packs the flipped-out U34 deeply into the catalytic pocket and triggers the activation of the catalytic cysteine residues. The adenylated RNA intermediate is trapped. Thus, the active closed-conformation of the complex ensures accurate sulphur incorporation into the activated uridine carbon by forming a catalytic chamber to prevent solvent from accessing the catalytic site. The structures of the complex with glutamate tRNA further reveal how MnmA specifically recognizes its three different tRNA substrates. These findings provide the structural basis for a general mechanism whereby an enzyme incorporates a reactive atom at a precise position in a biological molecule.


    Organizational Affiliation

    Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama-shi, Kanagawa 226-8501, Japan.




Macromolecules

Find similar proteins by: Sequence  |  Structure


Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
tRNA-specific 2-thiouridylase mnmA
A, B
380Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: mnmA (asuE, trmU, ycfB)
EC: 2.8.1.13
Find proteins for P25745 (Escherichia coli (strain K12))
Go to UniProtKB:  P25745
Entity ID: 1
MoleculeChainsLengthOrganism
tRNAC,D76N/A
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

Download SDF File 
Download CCD File 
A, B, C
PHOSPHATE ION
O4 P
NBIIXXVUZAFLBC-UHFFFAOYSA-K
 Ligand Interaction
SO4
Query on SO4

Download SDF File 
Download CCD File 
A, B
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.1 Å
  • R-Value Free: 0.269 
  • R-Value Work: 0.219 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 225.389α = 90.00
b = 175.845β = 101.62
c = 52.965γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data collection
CNSphasing
CNSrefinement
SCALEPACKdata scaling
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-08-15
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance