3H4F

Met62Leu variant of nitrite reductase from Alcaligenes faeclis


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.166 
  • R-Value Observed: 0.170 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Directed evolution of copper nitrite reductase to a chromogenic reductant.

Macpherson, I.S.Rosell, F.I.Scofield, M.Mauk, A.G.Murphy, M.E.

(2010) Protein Eng Des Sel 23: 137-145

  • DOI: 10.1093/protein/gzp084
  • Primary Citation of Related Structures:  
    3H56, 3H4H, 3H4F

  • PubMed Abstract: 
  • Directed evolution methods were developed for Cu-containing nitrite reductase (NiR) from Alcaligenes faecalis S-6. The PCR cloning strategy allows for the efficient production of libraries of 100 000 clones by a modification of a megaprimer-based who ...

    Directed evolution methods were developed for Cu-containing nitrite reductase (NiR) from Alcaligenes faecalis S-6. The PCR cloning strategy allows for the efficient production of libraries of 100 000 clones by a modification of a megaprimer-based whole-plasmid synthesis reaction. The high-throughput screen includes colony lift onto a nylon membrane and subsequent lysis of NiR-expressing colonies in the presence of Cu(2+) ions for copper incorporation into intracellularly expressed NiR. Addition of a chromogenic substrate, 3, 3'-diaminobenzidine (DAB), results in deposition of red, insoluble color at the site of oxidation by functional NiR. Twenty-thousand random variants of NiR were screened for improved function with DAB as a reductant, and five variants were identified. These variants were shuffled and screened, yielding two double variants. An analog of the DAB substrate, o-dianisidine, which is oxidized to a water-soluble product was used for functional characterization. The double variant M150L/F312C was most proficient at o-dianisidine oxidation with dioxygen as the electron acceptor (5.5X wt), and the M150L single variant was most proficient at o-dianisidine oxidation with nitrite as the electron acceptor (8.5X wt). The library generation and screening method can be employed for evolving new reductase functions in NiR and for screening of efficient folding of engineered NiRs.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, Canada.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Copper-containing nitrite reductaseABC336Alcaligenes faecalisMutation(s): 1 
Gene Names: nirnirK
EC: 1.7.2.1
Find proteins for P38501 (Alcaligenes faecalis)
Explore P38501 
Go to UniProtKB:  P38501
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.166 
  • R-Value Observed: 0.170 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 61.132α = 90
b = 102.223β = 90
c = 146.145γ = 90
Software Package:
Software NamePurpose
REFMACrefinement

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-02-02
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance