The repressor PrtR1 and the global H-NS-like regulators MvaT and MvaV enable the fine-tuning of R-tailocin expression in Pseudomonas protegens

Abstract Background Bacteria rely on an arsenal of weapons to challenge their opponents in highly competitive environments. To specifically counter closely related bacteria, specialized weapons with a narrow activity spectrum are deployed, particularly contractile phage tail-like particles or R-tail...

Full description

Saved in:
Bibliographic Details
Main Authors: Clara Margot Heiman, Hammam Antar, Florian Fournes, Christoph Keel, Jordan Vacheron
Format: Article
Language:English
Published: BMC 2025-05-01
Series:BMC Microbiology
Subjects:
Online Access:https://doi.org/10.1186/s12866-025-03983-9
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849312168480079872
author Clara Margot Heiman
Hammam Antar
Florian Fournes
Christoph Keel
Jordan Vacheron
author_facet Clara Margot Heiman
Hammam Antar
Florian Fournes
Christoph Keel
Jordan Vacheron
author_sort Clara Margot Heiman
collection DOAJ
description Abstract Background Bacteria rely on an arsenal of weapons to challenge their opponents in highly competitive environments. To specifically counter closely related bacteria, specialized weapons with a narrow activity spectrum are deployed, particularly contractile phage tail-like particles or R-tailocins. Their production leads to the lysis of the producing cells, indicating that their expression must be carefully orchestrated so that only a small percentage of cells produce R-tailocins for the benefit of the entire population. Results In this study, we set out to better understand how the production of these phage tail-like weapons is regulated in environmental pseudomonads using the competitive plant root colonizer and environmental model strain Pseudomonas protegens CHA0. Using an RNA sequencing (RNA-seq) approach, we found that genes involved in DNA repair, particularly the SOS response program, are upregulated following exposure of the pseudomonad to the DNA-damaging agents mitomycin C and hydrogen peroxide, while genes involved in cell division and primary metabolism are downregulated. The R-tailocin and prophage gene clusters were also upregulated in response to these DNA damaging agents. By combining reverse genetics, transcriptional reporters and chromatin immunoprecipitation sequencing (ChIP-seq), we show that the R-tailocin locus-specific LexA-like regulator PrtR1 represses R-tailocin gene expression by binding directly to the promoter region of the cluster, while the histone-like nucleoid structuring (H-NS) proteins MvaT and MvaV act as master regulators that indirectly regulate R-tailocin cluster expression. Conclusion Our results suggest that at least these three regulators operate in concert to ensure tight control of R-tailocin expression and cell lytic release in environmental Pseudomonas protegens strains.
format Article
id doaj-art-4bf0f9778db242b384e6e5a8d7e8ab4b
institution Kabale University
issn 1471-2180
language English
publishDate 2025-05-01
publisher BMC
record_format Article
series BMC Microbiology
spelling doaj-art-4bf0f9778db242b384e6e5a8d7e8ab4b2025-08-20T03:53:11ZengBMCBMC Microbiology1471-21802025-05-0125111610.1186/s12866-025-03983-9The repressor PrtR1 and the global H-NS-like regulators MvaT and MvaV enable the fine-tuning of R-tailocin expression in Pseudomonas protegensClara Margot Heiman0Hammam Antar1Florian Fournes2Christoph Keel3Jordan Vacheron4Department of Fundamental Microbiology, University of LausanneDepartment of Fundamental Microbiology, University of LausanneDepartment of Fundamental Microbiology, University of LausanneDepartment of Fundamental Microbiology, University of LausanneDepartment of Fundamental Microbiology, University of LausanneAbstract Background Bacteria rely on an arsenal of weapons to challenge their opponents in highly competitive environments. To specifically counter closely related bacteria, specialized weapons with a narrow activity spectrum are deployed, particularly contractile phage tail-like particles or R-tailocins. Their production leads to the lysis of the producing cells, indicating that their expression must be carefully orchestrated so that only a small percentage of cells produce R-tailocins for the benefit of the entire population. Results In this study, we set out to better understand how the production of these phage tail-like weapons is regulated in environmental pseudomonads using the competitive plant root colonizer and environmental model strain Pseudomonas protegens CHA0. Using an RNA sequencing (RNA-seq) approach, we found that genes involved in DNA repair, particularly the SOS response program, are upregulated following exposure of the pseudomonad to the DNA-damaging agents mitomycin C and hydrogen peroxide, while genes involved in cell division and primary metabolism are downregulated. The R-tailocin and prophage gene clusters were also upregulated in response to these DNA damaging agents. By combining reverse genetics, transcriptional reporters and chromatin immunoprecipitation sequencing (ChIP-seq), we show that the R-tailocin locus-specific LexA-like regulator PrtR1 represses R-tailocin gene expression by binding directly to the promoter region of the cluster, while the histone-like nucleoid structuring (H-NS) proteins MvaT and MvaV act as master regulators that indirectly regulate R-tailocin cluster expression. Conclusion Our results suggest that at least these three regulators operate in concert to ensure tight control of R-tailocin expression and cell lytic release in environmental Pseudomonas protegens strains.https://doi.org/10.1186/s12866-025-03983-9TailocinPyocinRegulationPseudomonasH-NS regulatorsSOS response
spellingShingle Clara Margot Heiman
Hammam Antar
Florian Fournes
Christoph Keel
Jordan Vacheron
The repressor PrtR1 and the global H-NS-like regulators MvaT and MvaV enable the fine-tuning of R-tailocin expression in Pseudomonas protegens
BMC Microbiology
Tailocin
Pyocin
Regulation
Pseudomonas
H-NS regulators
SOS response
title The repressor PrtR1 and the global H-NS-like regulators MvaT and MvaV enable the fine-tuning of R-tailocin expression in Pseudomonas protegens
title_full The repressor PrtR1 and the global H-NS-like regulators MvaT and MvaV enable the fine-tuning of R-tailocin expression in Pseudomonas protegens
title_fullStr The repressor PrtR1 and the global H-NS-like regulators MvaT and MvaV enable the fine-tuning of R-tailocin expression in Pseudomonas protegens
title_full_unstemmed The repressor PrtR1 and the global H-NS-like regulators MvaT and MvaV enable the fine-tuning of R-tailocin expression in Pseudomonas protegens
title_short The repressor PrtR1 and the global H-NS-like regulators MvaT and MvaV enable the fine-tuning of R-tailocin expression in Pseudomonas protegens
title_sort repressor prtr1 and the global h ns like regulators mvat and mvav enable the fine tuning of r tailocin expression in pseudomonas protegens
topic Tailocin
Pyocin
Regulation
Pseudomonas
H-NS regulators
SOS response
url https://doi.org/10.1186/s12866-025-03983-9
work_keys_str_mv AT claramargotheiman therepressorprtr1andtheglobalhnslikeregulatorsmvatandmvavenablethefinetuningofrtailocinexpressioninpseudomonasprotegens
AT hammamantar therepressorprtr1andtheglobalhnslikeregulatorsmvatandmvavenablethefinetuningofrtailocinexpressioninpseudomonasprotegens
AT florianfournes therepressorprtr1andtheglobalhnslikeregulatorsmvatandmvavenablethefinetuningofrtailocinexpressioninpseudomonasprotegens
AT christophkeel therepressorprtr1andtheglobalhnslikeregulatorsmvatandmvavenablethefinetuningofrtailocinexpressioninpseudomonasprotegens
AT jordanvacheron therepressorprtr1andtheglobalhnslikeregulatorsmvatandmvavenablethefinetuningofrtailocinexpressioninpseudomonasprotegens
AT claramargotheiman repressorprtr1andtheglobalhnslikeregulatorsmvatandmvavenablethefinetuningofrtailocinexpressioninpseudomonasprotegens
AT hammamantar repressorprtr1andtheglobalhnslikeregulatorsmvatandmvavenablethefinetuningofrtailocinexpressioninpseudomonasprotegens
AT florianfournes repressorprtr1andtheglobalhnslikeregulatorsmvatandmvavenablethefinetuningofrtailocinexpressioninpseudomonasprotegens
AT christophkeel repressorprtr1andtheglobalhnslikeregulatorsmvatandmvavenablethefinetuningofrtailocinexpressioninpseudomonasprotegens
AT jordanvacheron repressorprtr1andtheglobalhnslikeregulatorsmvatandmvavenablethefinetuningofrtailocinexpressioninpseudomonasprotegens