Biological Assembly 1  

 3D View: Structure | Ligand Interaction

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

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

Macromolecule Content

• Total Structure Weight: 31.12 kDa 
• Atom Count: 2282 
• Modelled Residue Count: 282 
• Deposited Residue Count: 282 
• Unique protein chains: 1

1AJ0

CRYSTAL STRUCTURE OF A TERNARY COMPLEX OF E. COLI DIHYDROPTEROATE SYNTHASE

• DOI: 10.2210/pdb1AJ0/pdb

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


• Deposited: 1997-05-14 Released: 1998-05-20 
• Deposition Author(s): Achari, A., Somers, D.O., Champness, J.N., Bryant, P.K., Rosemond, J., Stammers, D.K.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Work: 0.206 

Literature

Crystal structure of the anti-bacterial sulfonamide drug target dihydropteroate synthase.

Achari, A., Somers, D.O., Champness, J.N., Bryant, P.K., Rosemond, J., Stammers, D.K.

(1997) Nat Struct Biol 4: 490-497

• PubMed: 9187658 
• DOI: 10.1038/nsb0697-490
• Primary Citation of Related Structures:  
  1AJ0, 1AJ2, 1AJZ


• PubMed Abstract: 
  

Sulfonamides were amongst the first clinically useful antibacterial agents to be discovered. The identification of sulfanilamide as the active component of the dye Prontosil rubrum led to the synthesis of clinically useful analogues. Today sulfamethoxazole (in combination with trimethoprim), is used to treat urinary tract infections caused by bacteria such as Escherichia coli and is also a first-line treatment for pneumonia caused by the fungus Pneumocystis carinii, a common condition in AIDS patients. The site of action is the de novo folate biosynthesis enzyme dihydropteroate synthase (DHPS) where sulfonamides act as analogues of one of the substrates, para-aminobenzoic acid (pABA). We report here the crystal structure of E.coli DHPS at 2.0 A resolution refined to an R-factor of 0.185. The single domain of 282 residues forms an eight-stranded alpha/beta-barrel. The 7,8-dihydropterin pyrophosphate (DHPPP) substrate binds in a deep cleft in the barrel, whilst sulfanilamide binds closer to the surface. The DHPPP ligand site is highly conserved amongst prokaryotic and eukaryotic DHPSs.

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Organizational Affiliation: 

Glaxo Wellcome Research & Development, Beckenham, Kent, UK. [e-mail]

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
DIHYDROPTEROATE SYNTHASE	A	282	Escherichia coli	Mutation(s): 0  EC: 2.5.1.15
Find proteins for P0AC13 (Escherichia coli (strain K12)) Explore P0AC13  Go to UniProtKB:  P0AC13

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
PH2	C [auth A]	2-AMINO-6-HYDROXYMETHYL-7,8-DIHYDRO-3H-PTERIDIN-4-ONE C7 H9 N5 O2 CQQNNQTXUGLUEV-UHFFFAOYSA-N
SAN	D [auth A]	SULFANILAMIDE C6 H8 N2 O2 S FDDDEECHVMSUSB-UHFFFAOYSA-N
SO4	B [auth A]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Work: 0.206 
• Space Group: C 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 92.91	α = 90
b = 60.67	β = 114.67
c = 59.82	γ = 90

Software Package:

Software Name	Purpose
PROFFT	refinement
XENGEN	data reduction
XENGEN	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1997-05-14 
• Released Date: 1998-05-20 
Deposition Author(s): Achari, A., Somers, D.O., Champness, J.N., Bryant, P.K., Rosemond, J., Stammers, D.K.

Revision History  

• Version 1.0: 1998-05-20
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Derived calculations, Version format compliance