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Applying an Inducible Expression System to Study Interference of Bacterial Virulence Factors with Intracellular Signaling
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Pseudomonas Virulence Factor Produces Autoinducer (S)-Valdiazen

Drake M Crawford1, Jack C Roche1, Qiang Guo1,2

  • 1Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.

ACS Chemical Biology
|April 29, 2025
PubMed

Insights

Pseudomonas virulence factor (pvf) produces the autoinducer (S)-valdiazen, crucial for bacterial communication and virulence. This study identifies this molecule and suggests widespread bacterial production of similar diazeniumdiolate signals.

Area of Science:

  • Microbiology
  • Chemical Biology
  • Biochemistry

Background:

  • Pseudomonas virulence factor (pvf) regulates bacterial cell-to-cell communication and virulence through autoinducing small molecules.
  • Previous research linked pvf genes to diazeniumdiolate compounds, but the specific signal remained unidentified.

Purpose of the Study:

  • To identify the specific autoinducing small-molecule signal produced by Pseudomonas virulence factor (pvf).
  • To investigate the role of stereochemistry in signal activity and explore the prevalence of similar signals in bacteria.

Main Methods:

  • Chemical identification of the autoinducer produced by pvf in Pseudomonas entomophila.
  • Stereochemical analysis of related signals in Pseudomonas syringae.
  • Bioinformatic analysis to identify potential producers of diazeniumdiolate signals.
  • Chemical quenching assays using potassium permanganate.

Main Results:

  • Identified (S)-valdiazen as the autoinducer produced by pvf in P. entomophila.
  • Determined the (S)-stereochemistry of leudiazen from P. syringae, another diazeniumdiolate signal.
  • Bioinformatically identified 5383 bacterial species potentially producing diazeniumdiolate signals.
  • Demonstrated that the (S)-configuration is essential for valdiazen's signaling activity.

Conclusions:

  • The specific autoinducer (S)-valdiazen produced by pvf in P. entomophila has been identified.
  • The stereospecific biosynthesis and signaling of (S)-diazeniumdiolates are suggested by findings in two bacterial species.
  • This research provides a foundation for discovering novel diazeniumdiolate signals across diverse bacterial populations.

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