1B9L

7,8-DIHYDRONEOPTERIN TRIPHOSPHATE EPIMERASE

• PDB DOI: https://doi.org/10.2210/pdb1B9L/pdb

• Classification: ISOMERASE
• Organism(s): Escherichia coli
• Mutation(s): No 


• Deposited: 1999-02-11 Released: 2000-02-18 
• Deposition Author(s): Ploom, T., Haussmann, C., Hof, P., Steinbacher, S., Bacher, A., Richardson, J., Huber, R.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.259 
• R-Value Work: 0.188 

Literature

Crystal structure of 7,8-dihydroneopterin triphosphate epimerase.

Ploom, T., Haussmann, C., Hof, P., Steinbacher, S., Bacher, A., Richardson, J., Huber, R.

(1999) Structure 7: 509-516

• PubMed: 10378270 
• DOI: https://doi.org/10.1016/s0969-2126(99)80067-7
• Primary Citation of Related Structures:  
  1B9L


• PubMed Abstract: 
  

  Dihydroneopterin triphosphate (H2NTP) is the central substrate in the biosynthesis of folate and tetrahydrobiopterin. Folate serves as a cofactor in amino acid and purine biosynthesis and tetrahydrobiopterin is used as a cofactor in amino acid hydroxylation and nitric oxide synthesis. In bacteria, H2NTP enters the folate biosynthetic pathway after nonenzymatic dephosphorylation; in vertebrates, H2NTP is used to synthesize tetrahydrobiopterin. The dihydroneopterin triphosphate epimerase of Escherichia coli catalyzes the inversion of carbon 2' of H2NTP.

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Organizational Affiliation: 

Max-Planck-Institut für Biochemie, Abteilung Strukturforschung, Martins Germany. [e-mail]

Biological Assembly 1  

Global Symmetry: Dihedral - D4  (Explore in 3D)
Global Stoichiometry: Homo 8-mer - A8 

Biological assembly 1 assigned by authors and generated by PQS (software)

Biological Assembly 2  

Global Symmetry: Cyclic - C4  (Explore in 3D)
Global Stoichiometry: Homo 4-mer - A4 

Biological assembly 2 generated by PISA (software)

Biological Assembly 3  

Global Symmetry: Cyclic - C4  (Explore in 3D)
Global Stoichiometry: Homo 4-mer - A4 

Biological assembly 3 generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 112.82 kDa 
• Atom Count: 7,872 
• Modelled Residue Count: 952 
• Deposited Residue Count: 960 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN (EPIMERASE)	A, B, C, D, E, F, G, H	120	Escherichia coli	Mutation(s): 0
UniProt
Find proteins for P0AC19 (Escherichia coli (strain K12)) Explore P0AC19  Go to UniProtKB:  P0AC19

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.259 
• R-Value Work: 0.188 
• Space Group: P 4₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 69.68	α = 90
b = 69.68	β = 90
c = 239.72	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	refinement

Structure Validation

Entry History 

Deposition Data

• Released Date: 2000-02-18 
Deposition Author(s): Ploom, T., Haussmann, C., Hof, P., Steinbacher, S., Bacher, A., Richardson, J., Huber, R.

Revision History  

• Version 1.0: 2000-02-18
  Type: Initial release
  
• Version 1.1: 2008-04-26
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Derived calculations, Version format compliance
• Version 1.3: 2023-12-27
  Changes: Data collection, Database references