429D

CRYSTAL STRUCTURE OF A LEADZYME; METAL BINDING AND IMPLICATIONS FOR CATALYSIS


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.70 Å
  • R-Value Free: 0.275 
  • R-Value Work: 0.255 
  • R-Value Observed: 0.255 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Crystal structure of a lead-dependent ribozyme revealing metal binding sites relevant to catalysis.

Wedekind, J.E.McKay, D.B.

(1999) Nat Struct Biol 6: 261-268

  • DOI: 10.1038/6700
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • The leadzyme is a small RNA motif that catalyzes a site-specific, Pb2+-dependent cleavage reaction. As such, it is an example of a metal-dependent RNA enzyme. Here we describe the X-ray crystallographic structure of the leadzyme, which reveals two in ...

    The leadzyme is a small RNA motif that catalyzes a site-specific, Pb2+-dependent cleavage reaction. As such, it is an example of a metal-dependent RNA enzyme. Here we describe the X-ray crystallographic structure of the leadzyme, which reveals two independent molecules per asymmetric unit. Both molecules feature an internal loop in which a bulged purine base stack twists away from the helical stem. This kinks the backbone, rendering the phosphodiester bond susceptible to cleavage. The independent molecules have different conformations: one leadzyme copy coordinates Mg2+, whereas the other binds only Ba2+ or Pb2+. In the active site of the latter molecule, a single Ba2+ ion coordinates the 2'-OH nucleophile, and appears to mimic the binding of catalytic lead. These observations allow a bond cleavage reaction to be modeled, which reveals the minimal structural features necessary for catalysis by this small ribozyme.


    Organizational Affiliation

    Department of Structural Biology, Stanford University School of Medicine, California 94305-5126, USA. Wedekind@ribose.stanford.edu



Macromolecules
  • Find similar nucleic acids by: Sequence   |   Structure
Entity ID: 1
MoleculeChainsLengthOrganism
RNA (5'-R(*CP*GP*GP*AP*CP*CP*GP*AP*GP*CP*CP*AP*G)-3')A, C13N/A
  • Find similar nucleic acids by: Sequence   |   Structure
Entity ID: 2
MoleculeChainsLengthOrganism
RNA (5'-R(*GP*CP*UP*GP*GP*GP*AP*GP*UP*CP*C)-3')B, D11N/A
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MG
Query on MG

Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.70 Å
  • R-Value Free: 0.275 
  • R-Value Work: 0.255 
  • R-Value Observed: 0.255 
  • Space Group: P 61 2 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 60.4α = 90
b = 60.4β = 90
c = 133.1γ = 120
Software Package:
Software NamePurpose
SHARPphasing
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1999-03-01
    Type: Initial release
  • Version 1.1: 2008-05-22
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance