Biological Assembly 1  

 3D View: Structure | Electron Density

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

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly Evidence: gel filtration

Macromolecule Content

• Total Structure Weight: 13.74 kDa 
• Atom Count: 945 
• Residue Count: 118 
• Unique protein chains: 1

5WFT

PelB 319-436 from Pseudomonas aeruginosa PAO1

• DOI: 10.2210/pdb5WFT/pdb

• Classification: STRUCTURAL PROTEIN
• Organism(s): Pseudomonas aeruginosa PAO1
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2017-07-12 Released: 2017-10-04 
• Deposition Author(s): Marmont, L.S., Howell, P.L.
• Funding Organization(s): Canadian Institutes of Health Research (CIHR)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.82 Å
• R-Value Free: 0.272 
• R-Value Work: 0.215 
• R-Value Observed: 0.221 

Literature

PelA and PelB proteins form a modification and secretion complex essential for Pel polysaccharide-dependent biofilm formation in Pseudomonas aeruginosa.

Marmont, L.S., Whitfield, G.B., Rich, J.D., Yip, P., Giesbrecht, L.B., Stremick, C.A., Whitney, J.C., Parsek, M.R., Harrison, J.J., Howell, P.L.

(2017) J Biol Chem 292: 19411-19422

• PubMed: 28972168 
• DOI: 10.1074/jbc.M117.812842
• Structures With Same Primary Citation


• PubMed Abstract: 
  

The pellicle (PEL) polysaccharide is synthesized by the opportunistic pathogen Pseudomonas aeruginosa and is an important biofilm constituent critical for bacterial virulence and persistence. PEL is a cationic polymer that promotes cell-cell interactions within the biofilm matrix through electrostatic interactions with extracellular DNA. Translocation of PEL across the outer membrane is proposed to occur via PelB, a membrane-embedded porin with a large periplasmic domain predicted to contain 19 tetratricopeptide repeats (TPRs). TPR-containing domains are typically involved in protein-protein interactions, and we therefore sought to determine whether PelB serves as a periplasmic scaffold that recruits other components of the PEL secretion apparatus. In this study, we show that the TPR domain of PelB interacts with PelA, an enzyme with PEL deacetylase and hydrolase activities. Structure determination of PelB TPRs 8-11 enabled us to design systematic deletions of individual TPRs and revealed that repeats 9-14, which are required for the cellular localization of PelA with PelB are also essential for PEL-dependent biofilm formation. Copurification experiments indicated that the interaction between PelA and PelB is direct and that the deacetylase activity of PelA increases and its hydrolase activity decreases when these proteins interact. Combined, our results indicate that the TPR-containing domain of PelB localizes PelA to the PEL secretion apparatus within the periplasm and that this may allow for efficient deacetylation of PEL before its export from the cell.

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Organizational Affiliation: 

the Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
PelB	A	118	Pseudomonas aeruginosa PAO1	Mutation(s): 0  Gene Names: pelB, PA3063
Find proteins for Q9HZE5 (Pseudomonas aeruginosa (strain ATCC 15692 / DSM 22644 / CIP 104116 / JCM 14847 / LMG 12228 / 1C / PRS 101 / PAO1)) Go to UniProtKB:  Q9HZE5

Small Molecules

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.82 Å
• R-Value Free: 0.272 
• R-Value Work: 0.215 
• R-Value Observed: 0.221 
• Space Group: P 6₅ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 61.14	α = 90
b = 61.14	β = 90
c = 217.75	γ = 120

Software Package:

Software Name	Purpose
PHENIX	refinement
DENZO	data reduction
SCALEPACK	data scaling
SOLVE	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2017-07-12 
• Released Date: 2017-10-04 
Deposition Author(s): Marmont, L.S., Howell, P.L.

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Funding Organization	Location	Grant Number
Canadian Institutes of Health Research (CIHR)	Canada	--

Revision History 

• Version 1.0: 2017-10-04
  Type: Initial release
  
• Version 1.1: 2017-10-18
  Changes: Database references
• Version 1.2: 2017-12-13
  Changes: Database references
• Version 1.3: 2020-01-08
  Changes: Author supporting evidence