2ZYQ

Crystal structure of the HsaC extradiol dioxygenase from M. tuberculosis


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.223 
  • R-Value Work: 0.180 
  • R-Value Observed: 0.182 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Studies of a ring-cleaving dioxygenase illuminate the role of cholesterol metabolism in the pathogenesis of Mycobacterium tuberculosis.

Yam, K.C.D'Angelo, I.Kalscheuer, R.Zhu, H.Wang, J.X.Snieckus, V.Ly, L.H.Converse, P.J.Jacobs, W.R.Strynadka, N.Eltis, L.D.

(2009) PLoS Pathog 5: e1000344-e1000344

  • DOI: 10.1371/journal.ppat.1000344
  • Primary Citation of Related Structures:  
    2ZI8, 2ZYQ

  • PubMed Abstract: 
  • Mycobacterium tuberculosis, the etiological agent of TB, possesses a cholesterol catabolic pathway implicated in pathogenesis. This pathway includes an iron-dependent extradiol dioxygenase, HsaC, that cleaves catechols. Immuno-compromised mice infect ...

    Mycobacterium tuberculosis, the etiological agent of TB, possesses a cholesterol catabolic pathway implicated in pathogenesis. This pathway includes an iron-dependent extradiol dioxygenase, HsaC, that cleaves catechols. Immuno-compromised mice infected with a DeltahsaC mutant of M. tuberculosis H37Rv survived 50% longer than mice infected with the wild-type strain. In guinea pigs, the mutant disseminated more slowly to the spleen, persisted less successfully in the lung, and caused little pathology. These data establish that, while cholesterol metabolism by M. tuberculosis appears to be most important during the chronic stage of infection, it begins much earlier and may contribute to the pathogen's dissemination within the host. Purified HsaC efficiently cleaved the catecholic cholesterol metabolite, DHSA (3,4-dihydroxy-9,10-seconandrost-1,3,5(10)-triene-9,17-dione; k(cat)/K(m) = 14.4+/-0.5 microM(-1) s(-1)), and was inactivated by a halogenated substrate analogue (partition coefficient<50). Remarkably, cholesterol caused loss of viability in the DeltahsaC mutant, consistent with catechol toxicity. Structures of HsaC:DHSA binary complexes at 2.1 A revealed two catechol-binding modes: bidentate binding to the active site iron, as has been reported in similar enzymes, and, unexpectedly, monodentate binding. The position of the bicyclo-alkanone moiety of DHSA was very similar in the two binding modes, suggesting that this interaction is a determinant in the initial substrate-binding event. These data provide insights into the binding of catechols by extradiol dioxygenases and facilitate inhibitor design.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
PROBABLE BIPHENYL-2,3-DIOL 1,2-DIOXYGENASE BPHCAB300Mycobacterium tuberculosisMutation(s): 0 
EC: 1.13.11.39 (PDB Primary Data), 1.13.11.25 (UniProt)
Find proteins for P9WNW7 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Explore P9WNW7 
Go to UniProtKB:  P9WNW7
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
TAR
Query on TAR

Download CCD File 
B
D(-)-TARTARIC ACID
C4 H6 O6
FEWJPZIEWOKRBE-LWMBPPNESA-N
 Ligand Interaction
FE2
Query on FE2

Download CCD File 
A, B
FE (II) ION
Fe
CWYNVVGOOAEACU-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.223 
  • R-Value Work: 0.180 
  • R-Value Observed: 0.182 
  • Space Group: P 4 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 123.737α = 90
b = 123.737β = 90
c = 106.784γ = 90
Software Package:
Software NamePurpose
PHASERphasing
REFMACrefinement
MAR345dtbdata collection
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-03-10
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance