6OX6

Crystal structure of the complex between the Type VI effector Tas1 and its immunity protein


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.17 Å
  • R-Value Free: 0.231 
  • R-Value Work: 0.185 
  • R-Value Observed: 0.187 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

An interbacterial toxin inhibits target cell growth by synthesizing (p)ppApp.

Ahmad, S.Wang, B.Walker, M.D.Tran, H.R.Stogios, P.J.Savchenko, A.Grant, R.A.McArthur, A.G.Laub, M.T.Whitney, J.C.

(2019) Nature 575: 674-678

  • DOI: 10.1038/s41586-019-1735-9
  • Primary Citation of Related Structures:  
    6OTT, 6OX6

  • PubMed Abstract: 
  • Bacteria have evolved sophisticated mechanisms to inhibit the growth of competitors 1 . One such mechanism involves type VI secretion systems, which bacteria can use to inject antibacterial toxins directly into neighbouring cells. Many of ...

    Bacteria have evolved sophisticated mechanisms to inhibit the growth of competitors 1 . One such mechanism involves type VI secretion systems, which bacteria can use to inject antibacterial toxins directly into neighbouring cells. Many of these toxins target the integrity of the cell envelope, but the full range of growth inhibitory mechanisms remains unknown 2 . Here we identify a type VI secretion effector, Tas1, in the opportunistic pathogen Pseudomonas aeruginosa. The crystal structure of Tas1 shows that it is similar to enzymes that synthesize (p)ppGpp, a broadly conserved signalling molecule in bacteria that modulates cell growth rate, particularly in response to nutritional stress 3 . However, Tas1 does not synthesize (p)ppGpp; instead, it pyrophosphorylates adenosine nucleotides to produce (p)ppApp at rates of nearly 180,000 molecules per minute. Consequently, the delivery of Tas1 into competitor cells drives rapid accumulation of (p)ppApp, depletion of ATP, and widespread dysregulation of essential metabolic pathways, thereby resulting in target cell death. Our findings reveal a previously undescribed mechanism for interbacterial antagonism and demonstrate a physiological role for the metabolite (p)ppApp in bacteria.


    Organizational Affiliation

    David Braley Centre for Antibiotic Discovery, McMaster University, Hamilton, Ontario, Canada. jwhitney@mcmaster.ca.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Tas1A439Pseudomonas aeruginosaMutation(s): 0 
Gene Names: CGU42_21755IPC3_19385
EC: 3.2.2.5
Find proteins for Q9I739 (Pseudomonas aeruginosa (strain ATCC 15692 / DSM 22644 / CIP 104116 / JCM 14847 / LMG 12228 / 1C / PRS 101 / PAO1))
Explore Q9I739 
Go to UniProtKB:  Q9I739
Protein Feature View
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
PA14_01140B77Pseudomonas aeruginosaMutation(s): 0 
Gene Names: 
Find proteins for A0A090A233 (Pseudomonas aeruginosa)
Explore A0A090A233 
Go to UniProtKB:  A0A090A233
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ACT
Query on ACT

Download CCD File 
A
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
AL-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.17 Å
  • R-Value Free: 0.231 
  • R-Value Work: 0.185 
  • R-Value Observed: 0.187 
  • Space Group: P 43 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 66.631α = 90
b = 66.631β = 90
c = 148.307γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
PHENIXrefinement
HKL-3000data reduction
HKL-3000data scaling
PHENIXphasing
PHENIXmodel building
Cootmodel building

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)United StatesHHSN272201200026C
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)United StatesHHSN272201700060C

Revision History 

  • Version 1.0: 2019-09-18
    Type: Initial release
  • Version 1.1: 2019-11-06
    Changes: Data collection, Database references
  • Version 1.2: 2019-11-20
    Changes: Database references
  • Version 1.3: 2019-12-11
    Changes: Database references
  • Version 1.4: 2019-12-18
    Changes: Author supporting evidence