1XB8

Zn substituted form of D62C/K74C double mutant of Pseudomonas Aeruginosa Azurin


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.236 
  • R-Value Work: 0.192 
  • R-Value Observed: 0.194 

wwPDB Validation   3D Report Full Report


This is version 1.5 of the entry. See complete history


Literature

Effects of a novel disulfide bond and engineered electrostatic interactions on the thermostability of azurin

Tigerstrom, A.Schwarz, F.Karlsson, G.Okvist, M.Alvarez-Rua, C.Maeder, D.Robb, F.T.Sjolin, L.

(2004) Biochemistry 43: 12563-12574

  • DOI: https://doi.org/10.1021/bi048926x
  • Primary Citation of Related Structures:  
    1XB3, 1XB6, 1XB8

  • PubMed Abstract: 

    Identification and evaluation of factors important for thermostability in proteins is a growing research field with many industrial applications. This study investigates the effects of introducing a novel disulfide bond and engineered electrostatic interactions with respect to the thermostability of holo azurin from Pseudomonas aeruginosa. Four mutants were selected on the basis of rational design and novel temperature-dependent atomic displacement factors from crystal data collected at elevated temperatures. The atomic displacement parameters describe the molecular movement at higher temperatures. The thermostability was evaluated by optical spectroscopy as well as by differential scanning calorimetry. Although azurin has a high inherent stability, the introduction of a novel disulfide bond connecting a flexible loop with small alpha-helix (D62C/K74C copper-containing mutant), increased the T(m) by 3.7 degrees C compared with the holo protein. Furthermore, three mutants were designed to introduce electrostatic interactions, K24R, D23E/K128R, and D23E/K128R/K24R. Mutant K24R stabilizes loops between two separate beta-strands and D23E/K128R was selected to stabilize the C-terminus of azurin. Furthermore, D23E/K128R/K24R was selected to reflect the combination of the electrostatic interactions in D23E/K128R and K24R. The mutants involving electrostatic interactions had a minor effect on the thermostability. The crystal structures of the copper-containing mutants D62C/K74C and K24R have been determined to 1.5 and 1.8 A resolution. In addition the crystal structure of the zinc-loaded mutant D62C/K74C has also been completed to 1.8 A resolution. These structures support the selected design and provide valuable information for evaluating effects of the modifications on the thermostability of holo azurin.


  • Organizational Affiliation

    Department of Chemistry, Lundberg Institute, Göteborg University, Box 462, SE-405 30 Göteborg, Sweden.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
AzurinA,
B [auth C]
128Pseudomonas aeruginosaMutation(s): 2 
Gene Names: AZU
Membrane Entity: Yes 
UniProt
Find proteins for P00282 (Pseudomonas aeruginosa (strain ATCC 15692 / DSM 22644 / CIP 104116 / JCM 14847 / LMG 12228 / 1C / PRS 101 / PAO1))
Explore P00282 
Go to UniProtKB:  P00282
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP00282
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.236 
  • R-Value Work: 0.192 
  • R-Value Observed: 0.194 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 113.14α = 90
b = 50.038β = 119.51
c = 57.722γ = 90
Software Package:
Software NamePurpose
MOSFLMdata reduction
SCALAdata scaling
AMoREphasing
REFMACrefinement
CCP4data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2004-10-19
    Type: Initial release
  • Version 1.1: 2008-04-30
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Advisory, Version format compliance
  • Version 1.3: 2018-04-04
    Changes: Data collection
  • Version 1.4: 2021-10-20
    Changes: Database references, Derived calculations
  • Version 1.5: 2023-08-23
    Changes: Data collection, Refinement description