1FUR

FUMARASE MUTANT H188N WITH BOUND SUBSTRATE L-MALATE AT PUTATIVE ACTIVATOR SITE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.209 
  • R-Value Work: 0.170 
  • R-Value Observed: 0.170 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Mutations of fumarase that distinguish between the active site and a nearby dicarboxylic acid binding site.

Weaver, T.Lees, M.Banaszak, L.

(1997) Protein Sci 6: 834-842

  • DOI: 10.1002/pro.5560060410
  • Primary Citation of Related Structures:  
    2FUS, 1FUR

  • PubMed Abstract: 
  • Two mutant forms of fumarase C from E. coli have been made using PCR and recombinant DNA. The recombinant form of the protein included a histidine arm on the C-terminal facilitating purification. Based on earlier studies, two different carboxylic acid binding sites, labeled A- and B-, were observed in crystal structures of the wild type and inhibited forms of the enzyme ...

    Two mutant forms of fumarase C from E. coli have been made using PCR and recombinant DNA. The recombinant form of the protein included a histidine arm on the C-terminal facilitating purification. Based on earlier studies, two different carboxylic acid binding sites, labeled A- and B-, were observed in crystal structures of the wild type and inhibited forms of the enzyme. A histidine at each of the sites was mutated to an asparagine. H188N at the A-site resulted in a large decrease in specific activity, while the H129N mutation at the B-site had essentially no effect. From the results, we conclude that the A-site is indeed the active site, and a dual role for H188 as a potential catalytic base is proposed. Crystal structures of the two mutant proteins produced some unexpected results. Both mutations reduced the affinity for the carboxylic acids at their respective sites. The H129N mutant should be particularly useful in future kinetic studies because it sterically blocks the B-site with the carboxyamide of asparagine assuming the position of the ligand's carboxylate. In the H188N mutation at the active site, the new asparagine side chain still interacts with an active site water that appears to have moved slightly as a result of the mutation.


    Organizational Affiliation

    Department of Biochemistry, University of Minnesota, Minneapolis 55455, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
FUMARASE CA, B467Escherichia coliMutation(s): 1 
Gene Names: fumC
EC: 4.2.1.2
UniProt
Find proteins for P05042 (Escherichia coli (strain K12))
Explore P05042 
Go to UniProtKB:  P05042
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MLT
Query on MLT

Download Ideal Coordinates CCD File 
C [auth A], D [auth B]D-MALATE
C4 H6 O5
BJEPYKJPYRNKOW-UWTATZPHSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.209 
  • R-Value Work: 0.170 
  • R-Value Observed: 0.170 
  • Space Group: C 2 2 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 104.03α = 90
b = 219.32β = 90
c = 86.54γ = 90
Software Package:
Software NamePurpose
X-PLORmodel building
X-PLORrefinement
XENGENdata reduction
XENGENdata scaling
X-PLORphasing

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1997-07-23
    Type: Initial release
  • Version 1.1: 2008-03-03
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Version format compliance