1EYE

1.7 ANGSTROM RESOLUTION CRYSTAL STRUCTURE OF 6-HYDROXYMETHYL-7,8-DIHYDROPTEROATE SYNTHASE (DHPS) FROM MYCOBACTERIUM TUBERCULOSIS IN COMPLEX WITH 6-HYDROXYMETHYLPTERIN MONOPHOSPHATE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.70 Å
  • R-Value Free: 0.243 
  • R-Value Work: 0.185 
  • R-Value Observed: 0.185 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Crystal structure of Mycobacterium tuberculosis 7,8-dihydropteroate synthase in complex with pterin monophosphate: new insight into the enzymatic mechanism and sulfa-drug action.

Baca, A.M.Sirawaraporn, R.Turley, S.Sirawaraporn, W.Hol, W.G.

(2000) J Mol Biol 302: 1193-1212

  • DOI: 10.1006/jmbi.2000.4094
  • Primary Citation of Related Structures:  
    1EYE

  • PubMed Abstract: 
  • The enzyme 7,8-dihydropteroate synthase (DHPS) catalyzes the condensation of para-aminobenzoic acid (pABA) with 6-hydroxymethyl-7, 8-dihydropterin-pyrophosphate to form 7,8-dihydropteroate and pyrophosphate. DHPS is essential for the de novo synthesis of folate in prokaryotes, lower eukaryotes, and in plants, but is absent in mammals ...

    The enzyme 7,8-dihydropteroate synthase (DHPS) catalyzes the condensation of para-aminobenzoic acid (pABA) with 6-hydroxymethyl-7, 8-dihydropterin-pyrophosphate to form 7,8-dihydropteroate and pyrophosphate. DHPS is essential for the de novo synthesis of folate in prokaryotes, lower eukaryotes, and in plants, but is absent in mammals. Inhibition of this enzyme's activity by sulfonamide and sulfone drugs depletes the folate pool, resulting in growth inhibition and cell death. Here, we report the 1.7 A resolution crystal structure of the binary complex of 6-hydroxymethylpterin monophosphate (PtP) with DHPS from Mycobacterium tuberculosis (Mtb), a pathogen responsible for the death of millions of human beings each year. Comparison to other DHPS structures reveals that the M. tuberculosis DHPS structure is in a unique conformation in which loop 1 closes over the active site. The Mtb DHPS structure hints at a mechanism in which both loops 1 and 2 play important roles in catalysis by shielding the active site from bulk solvent and allowing pyrophosphoryl transfer to occur. A binding mode for pABA, sulfonamides and sulfones is suggested based on: (i) the new conformation of the closed loop 1; (ii) the distribution of dapsone and sulfonamide resistance mutations; (iii) the observed direction of the bond between the 6-methyl carbon atom and the bridging oxygen atom to the alpha-phosphate group in the Mtb DHPS:PtP binary complex; and (iv) the conformation of loop 2 in the Escherichia coli DHPS structure. Finally, the Mtb DHPS structure reveals a highly conserved pterin binding pocket that may be exploited for the design of novel antimycobacterial agents.


    Organizational Affiliation

    Department of Bioengineering and Biomolecular Structure Center, University of Washington, Seattle, WA 98195, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
DIHYDROPTEROATE SYNTHASE IA280Mycobacterium tuberculosis H37RvMutation(s): 0 
Gene Names: folP1Rv3608cMTCY07H7B.14
EC: 2.5.1.15
Find proteins for P9WND1 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Explore P9WND1 
Go to UniProtKB:  P9WND1
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PMM
Query on PMM

Download CCD File 
A
PTERIN-6-YL-METHYL-MONOPHOSPHATE
C7 H8 N5 O5 P
AJXFJEHKGGCFNM-UHFFFAOYSA-N
 Ligand Interaction
MG
Query on MG

Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.70 Å
  • R-Value Free: 0.243 
  • R-Value Work: 0.185 
  • R-Value Observed: 0.185 
  • Space Group: P 32 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 62.9α = 90
b = 62.9β = 90
c = 121.4γ = 120
Software Package:
Software NamePurpose
AMoREphasing
TNTrefinement
CCP4data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-10-11
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Version format compliance
  • Version 1.3: 2017-10-04
    Changes: Refinement description
  • Version 1.4: 2018-02-07
    Changes: Experimental preparation