2X30

Crystal structure of the r139n mutant of a bifunctional enzyme pria


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.273 
  • R-Value Work: 0.216 
  • R-Value Observed: 0.218 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Identification and Analysis of Residues Contained on Beta --> Alpha Loops of the Dual-Substrate (Betaalpha)(8) Phosphoribosyl Isomerase a (Pria) Specific for its Phosphoribosyl Anthranilate Isomerase Activity.

Noda-Garcia, L.Camacho-Zarco, A.R.Verdel-Aranda, K.Wright, H.Soberon, X.Fulop, V.Barona-Gomez, F.

(2010) Protein Sci 19: 535

  • DOI: 10.1002/pro.331
  • Primary Citation of Related Structures:  
    2X30

  • PubMed Abstract: 
  • A good model to experimentally explore evolutionary hypothesis related to enzyme function is the ancient-like dual-substrate (beta alpha)(8) phosphoribosyl isomerase A (PriA), which takes part in both histidine and tryptophan biosynthesis in Streptomyces coelicolor and related organisms ...

    A good model to experimentally explore evolutionary hypothesis related to enzyme function is the ancient-like dual-substrate (beta alpha)(8) phosphoribosyl isomerase A (PriA), which takes part in both histidine and tryptophan biosynthesis in Streptomyces coelicolor and related organisms. In this study, we determined the Michaelis-Menten enzyme kinetics for both isomerase activities in wild-type PriA from S. coelicolor and in selected single-residue monofunctional mutants, identified after Escherichia coli in vivo complementation experiments. Structural and functional analyses of a hitherto unnoticed residue contained on the functionally important beta --> alpha loop 5, namely, Arg(139), which was postulated on structural grounds to be important for the dual-substrate specificity of PriA, is presented for the first time. Indeed, enzyme kinetics analyses done on the mutant variants PriA_Ser(81)Thr and PriA_Arg(139)Asn showed that these residues, which are contained on beta --> alpha loops and in close proximity to the N-terminal phosphate-binding site, are essential solely for the phosphoribosyl anthranilate isomerase activity of PriA. Moreover, analysis of the X-ray crystallographic structure of PriA_Arg(139)Asn elucidated at 1.95 A herein strongly implicates the occurrence of conformational changes in this beta --> alpha loop as a major structural feature related to the evolution of the dual-substrate specificity of PriA. It is suggested that PriA has evolved by tuning a fine energetic balance that allows the sufficient degree of structural flexibility needed for accommodating two topologically dissimilar substrates--within a bifunctional and thus highly constrained active site--without compromising its structural stability.


    Organizational Affiliation

    Evolution of Metabolic Diversity Laboratory, Laboratorio Nacional de Genómica para la Biodiversidad (Langebio), CINVESTAV-IPN, Km 9.6 Libramiento Norte, Carretera Irapuato-León, Irapuato, C.P. 36822, México.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
PHOSPHORIBOSYL ISOMERASE AA240Streptomyces coelicolorMutation(s): 1 
EC: 5.3.1.16 (PDB Primary Data), 5.3.1.24 (PDB Primary Data)
Find proteins for P16250 (Streptomyces coelicolor (strain ATCC BAA-471 / A3(2) / M145))
Explore P16250 
Go to UniProtKB:  P16250
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download Ideal Coordinates CCD File 
B [auth A], C [auth A]SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.273 
  • R-Value Work: 0.216 
  • R-Value Observed: 0.218 
  • Space Group: P 31 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 63.6α = 90
b = 63.6β = 90
c = 102.9γ = 120
Software Package:
Software NamePurpose
REFMACrefinement
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2010-02-02
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Version format compliance
  • Version 1.2: 2018-01-24
    Changes: Source and taxonomy