Pseudomonas flexibilis GCN5 family acetyltransferase

Experimental Data Snapshot

  • Resolution: 3.04 Å
  • R-Value Free: 0.302 
  • R-Value Work: 0.225 
  • R-Value Observed: 0.233 

wwPDB Validation   3D Report Full Report

This is version 1.2 of the entry. See complete history


The novel type II toxin-antitoxin PacTA modulates Pseudomonas aeruginosa iron homeostasis by obstructing the DNA-binding activity of Fur.

Song, Y.Zhang, S.Ye, Z.Song, Y.Chen, L.Tong, A.He, Y.Bao, R.

(2022) Nucleic Acids Res 50: 10586-10600

  • DOI: https://doi.org/10.1093/nar/gkac867
  • Primary Citation of Related Structures:  
    8GXF, 8GXJ, 8GXK

  • PubMed Abstract: 

    Type II toxin-antitoxin (TA) systems are widely distributed in bacterial and archaeal genomes and are involved in diverse critical cellular functions such as defense against phages, biofilm formation, persistence, and virulence. GCN5-related N-acetyltransferase (GNAT) toxin, with an acetyltransferase activity-dependent mechanism of translation inhibition, represents a relatively new and expanding family of type II TA toxins. We here describe a group of GNAT-Xre TA modules widely distributed among Pseudomonas species. We investigated PacTA (one of its members encoded by PA3270/PA3269) from Pseudomonas aeruginosa and demonstrated that the PacT toxin positively regulates iron acquisition in P. aeruginosa. Notably, other than arresting translation through acetylating aminoacyl-tRNAs, PacT can directly bind to Fur, a key ferric uptake regulator, to attenuate its DNA-binding affinity and thus permit the expression of downstream iron-acquisition-related genes. We further showed that the expression of the pacTA locus is upregulated in response to iron starvation and the absence of PacT causes biofilm formation defect, thereby attenuating pathogenesis. Overall, these findings reveal a novel regulatory mechanism of GNAT toxin that controls iron-uptake-related genes and contributes to bacterial virulence.

  • Organizational Affiliation

    Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610093, China.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
GCN5 family acetyltransferaseA [auth B],
B [auth A],
193Pseudomonas flexibilisMutation(s): 0 
Gene Names: PT85_02890SAMN05421672_12249
Find proteins for A0A0B3C4T8 (Pseudomonas flexibilis)
Explore A0A0B3C4T8 
Go to UniProtKB:  A0A0B3C4T8
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupA0A0B3C4T8
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 3.04 Å
  • R-Value Free: 0.302 
  • R-Value Work: 0.225 
  • R-Value Observed: 0.233 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 43.889α = 90
b = 99.013β = 101.866
c = 98.822γ = 90
Software Package:
Software NamePurpose
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report

Entry History & Funding Information

Deposition Data

Funding OrganizationLocationGrant Number
National Natural Science Foundation of China (NSFC)China81871615

Revision History  (Full details and data files)

  • Version 1.0: 2022-10-19
    Type: Initial release
  • Version 1.1: 2022-11-02
    Changes: Database references
  • Version 1.2: 2023-11-08
    Changes: Data collection, Refinement description