2VOU

Structure of 2,6-dihydroxypyridine-3-hydroxylase from Arthrobacter nicotinovorans


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.222 
  • R-Value Work: 0.185 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structure of 2,6-Dihydroxypyridine 3-Hydroxylase from a Nicotine-Degrading Pathway.

Treiber, N.Schulz, G.E.

(2008) J.Mol.Biol. 379: 94

  • DOI: 10.1016/j.jmb.2008.03.032

  • PubMed Abstract: 
  • The enzyme 2,6-dihydroxypyridine-3-hydroxylase catalyzes the sixth step of the nicotine degradation pathway in Arthrobacter nicotinovorans. The enzyme was produced in Escherichia coli, purified and crystallized. The crystal structure was solved at 2. ...

    The enzyme 2,6-dihydroxypyridine-3-hydroxylase catalyzes the sixth step of the nicotine degradation pathway in Arthrobacter nicotinovorans. The enzyme was produced in Escherichia coli, purified and crystallized. The crystal structure was solved at 2.6 A resolution, revealing a significant structural relationship with the family of FAD-dependent aromatic hydroxylases, but essentially no sequence homology. The structure was aligned with those of the established family members, showing that the FAD molecules are bound at virtually identical locations. The reported enzyme is a dimer like most other family members, but its dimerization contact differs from the others. The binding position of NAD(P)H to this enzyme family is not clear. Since the reported enzyme accepts only NADH for flavin reduction in contrast to the other established members using NADPH, we searched through the structural alignment and found an indication for the position of the 2'-phosphate of NADPH that is in general agreement with mutational studies on a related enzyme, but contradicts a crystal soaking experiment. Using a bound glycerol molecule and the known substrate positions of three related enzymes as a guide, the substrate 2,6-dihydroxypyridine was placed into the active center. The access to the binding site is discussed. The new active center geometry introduces constraints that render some reaction scenarios more likely than others. It suggests that flavin is reduced at its out-position and then drawn into its in-position, where it binds molecular oxygen. The geometry is consistent with the proposal that peroxy-flavin is protonated by the solvent to yield the electrophilic hydroperoxy-flavin. The substrate is activated by two buried histidines but there is no appropriate base to store the surplus proton of the hydroxylated carbon atom. The implications of this problem are discussed.


    Organizational Affiliation

    Institut für Organische Chemie und Biochemie, Albert-Ludwigs-Universität, Albertstr. 21, 79104 Freiburg im Breisgau, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
2,6-DIHYDROXYPYRIDINE HYDROXYLASE
A, B, C
397Paenarthrobacter nicotinovoransMutation(s): 1 
Gene Names: dhpH
EC: 1.14.13.10
Find proteins for Q93NG3 (Paenarthrobacter nicotinovorans)
Go to UniProtKB:  Q93NG3
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ACT
Query on ACT

Download SDF File 
Download CCD File 
A, B, C
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
FAD
Query on FAD

Download SDF File 
Download CCD File 
A, B, C
FLAVIN-ADENINE DINUCLEOTIDE
C27 H33 N9 O15 P2
VWWQXMAJTJZDQX-UYBVJOGSSA-N
 Ligand Interaction
GOL
Query on GOL

Download SDF File 
Download CCD File 
A, B, C
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.222 
  • R-Value Work: 0.185 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 185.960α = 90.00
b = 185.960β = 90.00
c = 104.760γ = 120.00
Software Package:
Software NamePurpose
SHARPphasing
XSCALEdata scaling
SHELXDphasing
XDSdata reduction
REFMACrefinement
autoSHARPphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-05-13
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Refinement description, Version format compliance