2ZQB

Crystal structure of a psychrotrophic RNaseHI variant with sextuple thermostabilizing mutations


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.49 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.193 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Destabilization of psychrotrophic RNase HI in a localized fashion as revealed by mutational and X-ray crystallographic analyses

Rohman, M.S.Tadokoro, T.Angkawidjaja, C.Abe, Y.Matsumura, H.Koga, Y.Takano, K.Kanaya, S.

(2009) Febs J. 276: 603-613

  • DOI: 10.1111/j.1742-4658.2008.06811.x

  • PubMed Abstract: 
  • The Arg97 --> Gly and Asp136 --> His mutations stabilized So-RNase HI from the psychrotrophic bacterium Shewanella oneidensis MR-1 by 5.4 and 9.7 degrees C, respectively, in T(m), and 3.5 and 6.1 kJ x mol(-1), respectively, in DeltaG(H2O). These muta ...

    The Arg97 --> Gly and Asp136 --> His mutations stabilized So-RNase HI from the psychrotrophic bacterium Shewanella oneidensis MR-1 by 5.4 and 9.7 degrees C, respectively, in T(m), and 3.5 and 6.1 kJ x mol(-1), respectively, in DeltaG(H2O). These mutations also stabilized the So-RNase HI derivative (4x-RNase HI) with quadruple thermostabilizing mutations in an additive manner. As a result, the resultant sextuple mutant protein (6x-RNase HI) was more stable than the wild-type protein by 28.8 degrees C in T(m) and 27.0 kJ x mol(-1) in DeltaG(H2O). To analyse the effects of the mutations on the protein structure, the crystal structure of the 6x-RNase HI protein was determined at 2.5 A resolution. The main chain fold and interactions of the side-chains of the 6x-RNase HI protein were basically identical to those of the wild-type protein, except for the mutation sites. These results indicate that all six mutations independently affect the protein structure, and are consistent with the fact that the thermostabilizing effects of the mutations are roughly additive. The introduction of favourable interactions and the elimination of unfavourable interactions by the mutations contribute to the stabilization of the 6x-RNase HI protein. We propose that So-RNase HI is destabilized when compared with its mesophilic and thermophilic counterparts in a localized fashion by increasing the number of amino acid residues unfavourable for protein stability.


    Organizational Affiliation

    Department of Material and Life Science, Graduate School of Engineering, Osaka University, Japan.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Ribonuclease HI
A, B, C, D
158Shewanella oneidensis (strain MR-1)Gene Names: rnhA
EC: 3.1.26.4
Find proteins for Q8EE30 (Shewanella oneidensis (strain MR-1))
Go to UniProtKB:  Q8EE30
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

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

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.49 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.193 
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 68.239α = 90.00
b = 68.239β = 90.00
c = 272.816γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data collection
REFMACrefinement
HKL-2000data scaling
HKL-2000data reduction
MOLREPphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-06-23
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance