2G8F

B. halodurans RNase H catalytic domain E188A mutant in complex with Mg2+ and RNA/DNA hybrid (non-P nick at the active site)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.65 Å
  • R-Value Work: 0.182 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Stepwise analyses of metal ions in RNase H catalysis from substrate destabilization to product release.

Nowotny, M.Yang, W.

(2006) EMBO J 25: 1924-1933

  • DOI: https://doi.org/10.1038/sj.emboj.7601076
  • Primary Citation of Related Structures:  
    2G8F, 2G8H, 2G8I, 2G8K, 2G8U, 2G8V, 2G8W

  • PubMed Abstract: 

    In two-metal catalysis, metal ion A has been proposed to activate the nucleophile and metal ion B to stabilize the transition state. We recently reported crystal structures of RNase H-RNA/DNA substrate complexes obtained at 1.5-2.2 Angstroms. We have now determined and report here structures of reaction intermediate and product complexes of RNase H at 1.65-1.85 Angstroms. The movement of the two metal ions suggests how they may facilitate RNA hydrolysis during the catalytic process. Firstly, metal ion A may assist nucleophilic attack by moving towards metal ion B and bringing the nucleophile close to the scissile phosphate. Secondly, metal ion B transforms from an irregular coordination in the substrate complex to a more regular geometry in the product complex. The exquisite sensitivity of Mg(2+) to the coordination environment likely destabilizes the enzyme-substrate complex and reduces the energy barrier to form product. Lastly, product release probably requires dissociation of metal ion A, which is inhibited by either high concentrations of divalent cations or mutation of an assisting protein residue.


  • Organizational Affiliation

    Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.


Macromolecules

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 3
MoleculeChains Sequence LengthOrganismDetailsImage
Ribonuclease HC [auth A]142Halalkalibacterium haloduransMutation(s): 1 
Gene Names: rnhA
EC: 3.1.26.4
UniProt
Find proteins for Q9KEI9 (Halalkalibacterium halodurans (strain ATCC BAA-125 / DSM 18197 / FERM 7344 / JCM 9153 / C-125))
Explore Q9KEI9 
Go to UniProtKB:  Q9KEI9
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ9KEI9
Sequence Annotations
Expand
  • Reference Sequence

Find similar nucleic acids by:  Sequence   |   3D Structure  

Entity ID: 1
MoleculeChains LengthOrganismImage
5'-R(*UP*CP*GP*AP*CP*A)-3'A [auth B]6N/A
Sequence Annotations
Expand
  • Reference Sequence

Find similar nucleic acids by:  Sequence   |   3D Structure  

Entity ID: 2
MoleculeChains LengthOrganismImage
5'-D(*AP*TP*GP*TP*CP*G)-3'B [auth C]6N/A
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.65 Å
  • R-Value Work: 0.182 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 82.072α = 90
b = 36.858β = 96.47
c = 61.796γ = 90
Software Package:
Software NamePurpose
HKL-2000data collection
SCALEPACKdata scaling
EPMRphasing
CNSrefinement
HKL-2000data reduction

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2006-04-25
    Type: Initial release
  • Version 1.1: 2008-05-01
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2021-10-20
    Changes: Database references, Derived calculations
  • Version 1.4: 2023-08-30
    Changes: Data collection, Refinement description