1QO2

Crystal structure of N-((5'-phosphoribosyl)-formimino)-5-aminoimidazol-4-carboxamid ribonucleotid isomerase (EC 3.1.3.15, HisA)

• PDB DOI: https://doi.org/10.2210/pdb1QO2/pdb

• Classification: ISOMERASE
• Organism(s): Thermotoga maritima
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1999-11-01 Released: 2000-07-12 
• Deposition Author(s): Wilmanns, M., Lang, D., Thoma, R., Sterner, R.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.85 Å
• R-Value Free: 0.246 
• R-Value Work: 0.188 
• R-Value Observed: 0.188 

Literature

Structural Evidence for Evolution of the Beta/Alpha-Barrel Scaffold by Repeated Gene Duplication and Fusion

Lang, D., Thoma, R., Henn-Sax, M., Sterner, R., Wilmanns, M.

(2000) Science 289: 1546

• PubMed: 10968789 
• DOI: https://doi.org/10.1126/science.289.5484.1546
• Primary Citation of Related Structures:  
  1QO2, 1THF


• PubMed Abstract: 
  

  The atomic structures of two proteins in the histidine biosynthesis pathway consist of beta/alpha barrels with a twofold repeat pattern. It is likely that these proteins evolved by twofold gene duplication and gene fusion from a common half-barrel ancestor. These ancestral domains are not visible as independent domains in the extant proteins but can be inferred from a combination of sequence and structural analysis. The detection of subdomain structures may be useful in efforts to search genome sequences for functionally and structurally related proteins.

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Organizational Affiliation: 

European Molecular Biology Laboratory (EMBL) Hamburg Outstation, EMBL c/o Deutsches Elektronen- Synchrotron (DESY), Notkestrasse 85, D-22603 Hamburg, Germany.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 generated by PQS (software)

Biological Assembly 2  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 generated by PQS (software)

Macromolecule Content

• Total Structure Weight: 54.42 kDa 
• Atom Count: 4,345 
• Modelled Residue Count: 482 
• Deposited Residue Count: 482 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
1-(5-phosphoribosyl)-5-[(5-phosphoribosylamino)methylideneamino] imidazole-4-carboxamide isomerase	A, B	241	Thermotoga maritima	Mutation(s): 0  Gene Names: THISA EC: 5.3.1.15 (PDB Primary Data), 5.3.1.16 (UniProt)
UniProt
Find proteins for Q9X0C7 (Thermotoga maritima (strain ATCC 43589 / DSM 3109 / JCM 10099 / NBRC 100826 / MSB8)) Explore Q9X0C7  Go to UniProtKB:  Q9X0C7

Small Molecules

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A, B	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.85 Å
• R-Value Free: 0.246 
• R-Value Work: 0.188 
• R-Value Observed: 0.188 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 46.78	α = 90
b = 73.16	β = 97.42
c = 62.7	γ = 90

Software Package:

Software Name	Purpose
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling
CNS	phasing
SHARP	phasing
SOLVE	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2000-07-12 
Deposition Author(s): Wilmanns, M., Lang, D., Thoma, R., Sterner, R.

Revision History  

• Version 1.0: 2000-07-12
  Type: Initial release
  
• Version 1.1: 2011-05-08
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2019-05-22
  Changes: Data collection, Derived calculations, Other, Refinement description
• Version 1.4: 2019-07-24
  Changes: Data collection
• Version 1.5: 2024-10-23
  Changes: Data collection, Database references, Structure summary