3N1Y

X-ray Crystal Structure of Toluene/o-Xylene Monooxygenase Hydroxylase T201G Mutant


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.235 
  • R-Value Work: 0.223 
  • R-Value Observed: 0.223 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Active Site Threonine Facilitates Proton Transfer during Dioxygen Activation at the Diiron Center of Toluene/o-Xylene Monooxygenase Hydroxylase.

Song, W.J.McCormick, M.S.Behan, R.K.Sazinsky, M.H.Jiang, W.Lin, J.Krebs, C.Lippard, S.J.

(2010) J Am Chem Soc 132: 13582-13585

  • DOI: 10.1021/ja1063795
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Toluene/o-xylene monooxygenase hydroxylase (ToMOH), a diiron-containing enzyme, can activate dioxygen to oxidize aromatic substrates. To elucidate the role of a strictly conserved T201 residue during dioxygen activation of the enzyme, T201S, T201G, T ...

    Toluene/o-xylene monooxygenase hydroxylase (ToMOH), a diiron-containing enzyme, can activate dioxygen to oxidize aromatic substrates. To elucidate the role of a strictly conserved T201 residue during dioxygen activation of the enzyme, T201S, T201G, T201C, and T201V variants of ToMOH were prepared by site-directed mutagenesis. X-ray crystal structures of all the variants were obtained. Steady-state activity, regiospecificity, and single-turnover yields were also determined for the T201 mutants. Dioxygen activation by the reduced T201 variants was explored by stopped-flow UV-vis and Mössbauer spectroscopy. These studies demonstrate that the dioxygen activation mechanism is preserved in all T201 variants; however, both the formation and decay kinetics of a peroxodiiron(III) intermediate, T201(peroxo), were greatly altered, revealing that T201 is critically involved in dioxygen activation. A comparison of the kinetics of O(2) activation in the T201S, T201C, and T201G variants under various reaction conditions revealed that T201 plays a major role in proton transfer, which is required to generate the peroxodiiron(III) intermediate. A mechanism is postulated for dioxygen activation, and possible structures of oxygenated intermediates are discussed.


    Organizational Affiliation

    Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Toluene o-xylene monooxygenase componentA498Pseudomonas sp. OX1Mutation(s): 1 
Gene Names: touA
Find proteins for Q6IV66 (Pseudomonas sp. OX1)
Explore Q6IV66 
Go to UniProtKB:  Q6IV66
Protein Feature View
 ( Mouse scroll to zoom / Hold left click to move )
  • Reference Sequence

Find similar proteins by: Sequence  |  Structure

Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Toluene o-xylene monooxygenase componentB330Pseudomonas sp. OX1Mutation(s): 0 
Gene Names: touE
Find proteins for Q6IV62 (Pseudomonas sp. OX1)
Explore Q6IV62 
Go to UniProtKB:  Q6IV62
Protein Feature View
 ( Mouse scroll to zoom / Hold left click to move )
  • Reference Sequence

Find similar proteins by: Sequence  |  Structure

Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Toluene o-xylene monooxygenase componentC86Pseudomonas sp. OX1Mutation(s): 0 
Gene Names: touB
Find proteins for Q6IV65 (Pseudomonas sp. OX1)
Explore Q6IV65 
Go to UniProtKB:  Q6IV65
Protein Feature View
 ( Mouse scroll to zoom / Hold left click to move )
  • Reference Sequence
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
P6G
Query on P6G

Download CCD File 
A
HEXAETHYLENE GLYCOL
C12 H26 O7
IIRDTKBZINWQAW-UHFFFAOYSA-N
 Ligand Interaction
GOL
Query on GOL

Download CCD File 
A
GLYCEROL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
FE
Query on FE

Download CCD File 
A
FE (III) ION
Fe
VTLYFUHAOXGGBS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.235 
  • R-Value Work: 0.223 
  • R-Value Observed: 0.223 
  • Space Group: P 31 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 182.974α = 90
b = 182.974β = 90
c = 68.71γ = 120
Software Package:
Software NamePurpose
Blu-Icedata collection
EPMRphasing
CNSrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-10-13
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Source and taxonomy, Version format compliance