2OK4

Crystal structure of aromatic amine dehydrogenase TTQ-phenylacetaldehyde adduct oxidized with ferricyanide


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.45 Å
  • R-Value Free: 0.188 
  • R-Value Work: 0.154 
  • R-Value Observed: 0.156 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

New insights into the reductive half-reaction mechanism of aromatic amine dehydrogenase revealed by reaction with carbinolamine substrates.

Roujeinikova, A.Hothi, P.Masgrau, L.Sutcliffe, M.J.Scrutton, N.S.Leys, D.

(2007) J Biol Chem 282: 23766-23777

  • DOI: 10.1074/jbc.M700677200
  • Primary Citation of Related Structures:  
    2OIZ, 2OK4, 2OJY, 2OK6, 2I0T, 2I0S, 2I0R

  • PubMed Abstract: 
  • Aromatic amine dehydrogenase uses a tryptophan tryptophylquinone (TTQ) cofactor to oxidatively deaminate primary aromatic amines. In the reductive half-reaction, a proton is transferred from the substrate C1 to betaAsp-128 O-2, in a reaction that proceeds by H-tunneling ...

    Aromatic amine dehydrogenase uses a tryptophan tryptophylquinone (TTQ) cofactor to oxidatively deaminate primary aromatic amines. In the reductive half-reaction, a proton is transferred from the substrate C1 to betaAsp-128 O-2, in a reaction that proceeds by H-tunneling. Using solution studies, kinetic crystallography, and computational simulation we show that the mechanism of oxidation of aromatic carbinolamines is similar to amine oxidation, but that carbinolamine oxidation occurs at a substantially reduced rate. This has enabled us to determine for the first time the structure of the intermediate prior to the H-transfer/reduction step. The proton-betaAsp-128 O-2 distance is approximately 3.7A, in contrast to the distance of approximately 2.7A predicted for the intermediate formed with the corresponding primary amine substrate. This difference of approximately 1.0 A is due to an unexpected conformation of the substrate moiety, which is supported by molecular dynamic simulations and reflected in the approximately 10(7)-fold slower TTQ reduction rate with phenylaminoethanol compared with that with primary amines. A water molecule is observed near TTQ C-6 and is likely derived from the collapse of the preceding carbinolamine TTQ-adduct. We suggest this water molecule is involved in consecutive proton transfers following TTQ reduction, and is ultimately repositioned near the TTQ O-7 concomitant with protein rearrangement. For all carbinolamines tested, highly stable amide-TTQ adducts are formed following proton abstraction and TTQ reduction. Slow hydrolysis of the amide occurs after, rather than prior to, TTQ oxidation and leads ultimately to a carboxylic acid product.


    Organizational Affiliation

    Manchester Interdisciplinary Biocenter, University of Manchester, Manchester M17DN, United Kingdom.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Aromatic amine dehydrogenase, small subunit DH135Alcaligenes faecalisMutation(s): 1 
Gene Names: aauA
EC: 1.4.99.4 (PDB Primary Data), 1.4.9.2 (UniProt)
Find proteins for P84887 (Alcaligenes faecalis)
Explore P84887 
Go to UniProtKB:  P84887
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Aromatic amine dehydrogenase, large subunit AB361Alcaligenes faecalisMutation(s): 0 
Gene Names: aauB
EC: 1.4.99.4 (PDB Primary Data), 1.4.9.2 (UniProt)
Find proteins for P84888 (Alcaligenes faecalis)
Explore P84888 
Go to UniProtKB:  P84888
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
HY1
Query on HY1

Download Ideal Coordinates CCD File 
D, H
PHENYLACETALDEHYDE
C8 H8 O
DTUQWGWMVIHBKE-UHFFFAOYSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
TQQ
Query on TQQ
D,HL-PEPTIDE LINKINGC11 H11 N3 O3TRP
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.45 Å
  • R-Value Free: 0.188 
  • R-Value Work: 0.154 
  • R-Value Observed: 0.156 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 70.807α = 90
b = 88.957β = 90.31
c = 81.016γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
MOSFLMdata reduction
CCP4data scaling

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2007-05-01
    Type: Initial release
  • Version 1.1: 2008-02-06
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Version format compliance