2Y27

crystal structure of PaaK1 in complex with ATP from Burkholderia cenocepacia


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.194 
  • R-Value Work: 0.164 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Defining a Structural and Kinetic Rationale for Paralogous Copies of Phenylacetate-Coa Ligases from the Cystic Fibrosis Pathogen Burkholderia Cenocepacia J2315.

Law, A.Boulanger, M.J.

(2011) J.Biol.Chem. 286: 15577

  • DOI: 10.1074/jbc.M111.219683
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The phenylacetic acid (PAA) degradation pathway is the sole aerobic route for phenylacetic acid metabolism in bacteria and facilitates degradation of environmental pollutants such as styrene and ethylbenzene. The PAA pathway also is implicated in pro ...

    The phenylacetic acid (PAA) degradation pathway is the sole aerobic route for phenylacetic acid metabolism in bacteria and facilitates degradation of environmental pollutants such as styrene and ethylbenzene. The PAA pathway also is implicated in promoting Burkholderia cenocepacia infections in cystic fibrosis patients. Intriguingly, the first enzyme in the PAA pathway is present in two copies (paaK1 and paaK2), yet each subsequent enzyme is present in only a single copy. Furthermore, sequence divergence indicates that PaaK1 and PaaK2 form a unique subgroup within the adenylate-forming enzyme (AFE) superfamily. To establish a biochemical rationale for the existence of the PaaK paralogs in B. cenocepacia, we present high resolution x-ray crystal structures of a selenomethionine derivative of PaaK1 in complex with ATP and adenylated phenylacetate intermediate complexes of PaaK1 and PaaK2 in distinct conformations. Structural analysis reveals a novel N-terminal microdomain that may serve to recruit subsequent PAA enzymes, whereas a bifunctional role is proposed for the P-loop in stabilizing the C-terminal domain in conformation 2. The potential for different kinetic profiles was suggested by a structurally divergent extension of the aryl substrate pocket in PaaK1 relative to PaaK2. Functional characterization confirmed this prediction, with PaaK1 possessing a lower K(m) for phenylacetic acid and better able to accommodate 3' and 4' substitutions on the phenyl ring. Collectively, these results offer detailed insight into the reaction mechanism of a novel subgroup of the AFE superfamily and provide a clear biochemical rationale for the presence of paralogous copies of PaaK of B. cenocepacia.


    Organizational Affiliation

    Department of Biochemistry & Microbiology, University of Victoria, Victoria, British Columbia V8W 3P6, Canada.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PHENYLACETATE-COENZYME A LIGASE
A, B
437Burkholderia cenocepacia (strain ATCC BAA-245 / DSM 16553 / LMG 16656 / NCTC 13227 / J2315 / CF5610)Mutation(s): 0 
Gene Names: paaK
EC: 6.2.1.30
Find proteins for B4E7B5 (Burkholderia cenocepacia (strain ATCC BAA-245 / DSM 16553 / LMG 16656 / NCTC 13227 / J2315 / CF5610))
Go to UniProtKB:  B4E7B5
Small Molecules
Ligands 6 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ATP
Query on ATP

Download SDF File 
Download CCD File 
A, B
ADENOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O13 P3
ZKHQWZAMYRWXGA-KQYNXXCUSA-N
 Ligand Interaction
SCN
Query on SCN

Download SDF File 
Download CCD File 
A, B
THIOCYANATE ION
C N S
ZMZDMBWJUHKJPS-UHFFFAOYSA-M
 Ligand Interaction
GOL
Query on GOL

Download SDF File 
Download CCD File 
A, B
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
PG4
Query on PG4

Download SDF File 
Download CCD File 
A
TETRAETHYLENE GLYCOL
C8 H18 O5
UWHCKJMYHZGTIT-UHFFFAOYSA-N
 Ligand Interaction
BME
Query on BME

Download SDF File 
Download CCD File 
A, B
BETA-MERCAPTOETHANOL
C2 H6 O S
DGVVWUTYPXICAM-UHFFFAOYSA-N
 Ligand Interaction
MG
Query on MG

Download SDF File 
Download CCD File 
A, B
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A, B
L-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.194 
  • R-Value Work: 0.164 
  • Space Group: P 1
Unit Cell:
Length (Å)Angle (°)
a = 56.710α = 90.97
b = 62.470β = 109.81
c = 78.490γ = 106.51
Software Package:
Software NamePurpose
SHELXCDEphasing
REFMACrefinement
iMOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-05-04
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-07-12
    Type: Derived calculations