Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 34.84 kDa 
• Atom Count: 2580 
• Residue Count: 301 
• Unique protein chains: 1

5HIQ

Crystal Structure of PQS Response Protein PqsE in Complex with 2-(1H-pyrrol-1-yl)benzoic acid

• DOI: 10.2210/pdb5HIQ/pdb

• Classification: METAL BINDING PROTEIN
• Organism(s): Pseudomonas aeruginosa PAO1
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2016-01-12 Released: 2016-04-27 
• Deposition Author(s): Witzgall, F., Blankenfeldt, W.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Free: 0.236 
• R-Value Work: 0.193 
• R-Value Observed: 0.195 

Literature

Dissecting the Multiple Roles of PqsE in Pseudomonas aeruginosa Virulence by Discovery of Small Tool Compounds.

Zender, M., Witzgall, F., Drees, S.L., Weidel, E., Maurer, C.K., Fetzner, S., Blankenfeldt, W., Empting, M., Hartmann, R.W.

(2016) ACS Chem Biol 11: 1755-1763

• PubMed: 27082157 
• DOI: 10.1021/acschembio.6b00156
• Primary Citation of Related Structures:  
  5HIO, 5HIQ, 5HIP, 5HIS


• PubMed Abstract: 
  

Pseudomonas aeruginosa uses quorum sensing (QS) as a cell-to-cell communication system to orchestrate the expression of virulence determinants. The biosynthesis of the important Pseudomonas quinolone signal (PQS) requires the pqsABCDE operon. Here, PqsE acts as a pathway-specific thioesterase, but it also contributes to the regulation of bacterial virulence via an unknown mechanism. In this manuscript, we report the discovery of PqsE inhibitors as tool compounds to gain further insights into its different functions. Differential scanning fluorimetry (DSF) was used to screen a fragment library, and isothermal titration calorimetry (ITC) was employed as a secondary filter. As proven by X-ray crystallography, hit molecules bound to the active center inhibiting PqsE's thioesterase activity in cell-based and in vitro assays. Notably, the ligands did not affect the levels of the PqsE-regulated virulence factor pyocyanin. These findings indicate that the regulatory function of PqsE is not linked to its thioesterase activity and must be encoded outside of the active center. This study highlights the potential of fragment-based screening for the discovery of tool compounds. This approach provided novel insight into complex biological systems, which could not be obtained by knockout studies.

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Organizational Affiliation: 

Pharmaceutical and Medicinal Chemistry, Department of Pharmacy, Saarland University , Campus E8.1, 66123 Saarbrücken, Germany.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PqsE	A	303	Pseudomonas aeruginosa PAO1	Mutation(s): 0  Gene Names: PA1000, pqsE EC: 3.1.2.32
Find proteins for P20581 (Pseudomonas aeruginosa (strain ATCC 15692 / DSM 22644 / CIP 104116 / JCM 14847 / LMG 12228 / 1C / PRS 101 / PAO1)) Explore P20581  Go to UniProtKB:  P20581

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
60Q	A	2-pyrrol-1-ylbenzoic acid C11 H9 N O2 GNWTWXOZRSBCOZ-UHFFFAOYSA-N
FE	A	FE (III) ION Fe VTLYFUHAOXGGBS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Free: 0.236 
• R-Value Work: 0.193 
• R-Value Observed: 0.195 
• Space Group: P 3₂ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 60.88	α = 90
b = 60.88	β = 90
c = 146.212	γ = 120

Software Package:

Software Name	Purpose
Aimless	data scaling
PHENIX	refinement
PDB_EXTRACT	data extraction
XDS	data reduction
Coot	model building

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2016-01-12 
• Released Date: 2016-04-27 
Deposition Author(s): Witzgall, F., Blankenfeldt, W.

Revision History 

• Version 1.0: 2016-04-27
  Type: Initial release
  
• Version 1.1: 2016-06-29
  Changes: Database references