Related Experiment Video

Updated: Mar 26, 2026

Establishment of a High-throughput Setup for Screening Small Molecules That Modulate c-di-GMP Signaling in Pseudomonas aeruginosa
11:31

Establishment of a High-throughput Setup for Screening Small Molecules That Modulate c-di-GMP Signaling in Pseudomonas aeruginosa

Published on: June 30, 2016

9.2K

Functional Characterization of Pseudomonas Contact Dependent Growth Inhibition (CDI) Systems

Chryslène Mercy1,2, Bérengère Ize1, Suzana P Salcedo2

  • 1Laboratoire d'Ingénierie des Systèmes Macromoléculaires, CNRS UMR7255, Université Aix Marseille, Marseille, France.

Plos One
|January 26, 2016
PubMed

Insights

Contact-dependent inhibition (CDI) systems in Pseudomonas offer competitive advantages. These bacterial toxin-delivery systems are implicated in adhesion, biofilm formation, and niche adaptation.

Area of Science:

  • Microbiology
  • Bacterial Genetics
  • Molecular Biology

Background:

  • Contact-dependent inhibition (CDI) is a bacterial mechanism for inter-bacterial competition.
  • CDI systems involve toxins (CdiA-CT) and immunity proteins (CdiI).
  • CDI systems are widespread but previously undescribed in Pseudomonadaceae.

Purpose of the Study:

  • To identify and characterize functional CDI systems in the Pseudomonas genus.
  • To investigate the regulation and ecological role of CDI systems in Pseudomonas aeruginosa.

Main Methods:

  • Bioinformatic analysis to identify CDI toxin/immunity genes.
  • Experimental validation in Pseudomonas aeruginosa PAO1.
  • Identification of regulatory elements using genetic approaches.

Main Results:

  • Functional CDI toxin/immunity genes were identified in Pseudomonas.
  • Variability in peptide motifs delimiting CdiA-CT domains was observed.
  • The translational repressor RsmA was identified as a negative regulator of CDI systems.
  • CDI systems in P. aeruginosa are linked to adhesion, biofilm formation, and competitive fitness.

Conclusions:

  • CDI systems are present and functional in Pseudomonas, exhibiting novel variations.
  • RsmA plays a crucial role in regulating CDI system expression.
  • CDI systems likely contribute to niche adaptation and ecological success in Pseudomonadaceae.

More Related Videos

Use of the Soft-agar Overlay Technique to Screen for Bacterially Produced Inhibitory Compounds06:38

Use of the Soft-agar Overlay Technique to Screen for Bacterially Produced Inhibitory Compounds

Published on: January 14, 2017

34.3K
Deferred Growth Inhibition Assay to Quantify the Effect of Bacteria-derived Antimicrobials on Competition07:42

Deferred Growth Inhibition Assay to Quantify the Effect of Bacteria-derived Antimicrobials on Competition

Published on: September 3, 2016

15.7K

Related Concept Videos

Gene Regulation in Microbial Communities: Quorum Sensing01:28

Gene Regulation in Microbial Communities: Quorum Sensing

Quorum sensing is a mechanism of bacterial communication that enables coordinated gene expression in response to changes in population density. This facilitates collective behaviors that enhance survival, resource acquisition, and ecological adaptation. This process relies on small signaling molecules called autoinducers that accumulate as bacterial populations grow. When a critical threshold concentration of autoinducers is reached, bacterial cells collectively modify gene expression,...
868
Stringent Response in E. coli01:23

Stringent Response in E. coli

Bacterial growth is closely tied to nutrient availability, with cells proliferating exponentially under favorable conditions and entering a stationary phase when resources become scarce. This transition is mediated by a regulatory mechanism known as the stringent response, which allows bacteria to adapt to nutrient deprivation by modulating gene expression and metabolic activity.During nutrient scarcity, intracellular amino acid levels decline. It results in the accumulation of uncharged tRNAs...
465
Regulation of Bacterial Virulence01:28

Regulation of Bacterial Virulence

Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...
17
Inhibitors of Gram-positive Cell Wall Synthesis01:23

Inhibitors of Gram-positive Cell Wall Synthesis

Bacterial cell walls are typically rigid structures composed mainly of peptidoglycan, a mesh-like polymer that provides mechanical strength and maintains cell shape. The synthesis of peptidoglycan is a crucial process in bacterial growth and serves as a primary target for many antibiotics.Mechanism of Action of Beta-Lactam AntibioticsBeta-lactam antibiotics, such as penicillin, inhibit peptidoglycan synthesis in actively growing cells. These antibiotics share a characteristic four-membered...
33
Biological Methods for Microbial Control01:28

Biological Methods for Microbial Control

Biological agents offer an effective means of controlling microbial growth by leveraging natural processes like predation, competition, and the secretion of antimicrobial substances.Predatory bacteria such as Bdellovibrio species target and kill pathogens like Salmonella and E. coli. They are widely used in poultry farms to control infections. Myxococcus species help combat plant-pathogenic fungi. These naturally occurring predators serve as eco-friendly alternatives to chemical pesticides and...
1.3K
Defense Against Bacterial Pathogens01:31

Defense Against Bacterial Pathogens

The human immune system is a complex network of cells, tissues, and organs that work together to defend the body against bacterial infections. It consists of various immune cells, each playing a specific role in the defense mechanism.
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
3.4K