Related Experiment Video

Updated: Aug 15, 2026

Pseudomonas aeruginosa Induced Lung Injury Model
07:24

Pseudomonas aeruginosa Induced Lung Injury Model

Published on: October 29, 2014

Hypoxia Reduces the Pathogenicity of Pseudomonas aeruginosa by Decreasing the Expression of Multiple Virulence

Bettina Schaible1, Javier Rodriguez2, Amaya Garcia2

  • 1Conway Institute and.

The Journal of Infectious Diseases
|April 4, 2017
PubMed

Insights

Hypoxia, a low-oxygen environment, reduces the virulence of Pseudomonas aeruginosa, an opportunistic bacterium. This finding suggests targeting bacterial oxygen sensing mechanisms could treat infections.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Bacterial Pathogenesis

Background:

  • The influence of the microenvironment on opportunistic bacterial infections remains poorly understood.
  • Pseudomonas aeruginosa is an opportunistic pathogen causing infections in various clinical settings.

Purpose of the Study:

  • To investigate the role of hypoxia in regulating the virulence of Pseudomonas aeruginosa.
  • To identify mechanisms by which hypoxia affects bacterial pathogenicity.

Main Methods:

  • Comparative analysis of Pseudomonas aeruginosa strains from acute and chronic infections.
  • Exposure of bacterial strains to hypoxic conditions.
  • Mass spectrometric analysis of bacterial secretomes.
  • Assessment of bacterial pathogenicity in a murine model of pneumonia.
  • Evaluation of the role of Pseudomonas prolyl-hydroxylase domain-containing protein.

Main Results:

  • Pseudomonas aeruginosa strains from acute infections exhibit higher pathogenicity than those from chronic infections.
  • Hypoxia significantly attenuates the pathogenicity of acute infection strains, but not chronic ones.
  • Hypoxia induces repression of multiple virulence factors in Pseudomonas aeruginosa, independent of growth rate.
  • A Pseudomonas prolyl-hydroxylase domain-containing protein is implicated in sensing oxygen and regulating virulence factor expression.
  • Pharmacological inhibition of hydroxylases reduces virulence factor expression and pathogenicity in a pneumonia model.

Conclusions:

  • Hypoxia plays a crucial role in modulating the virulence of Pseudomonas aeruginosa.
  • Bacterial hydroxylases are key regulators of Pseudomonas aeruginosa virulence under hypoxic conditions.
  • Targeting bacterial oxygen sensing pathways, specifically hydroxylases, presents a potential therapeutic strategy against Pseudomonas aeruginosa infections.
Keywords:
Alkaline proteaseExotoxin AHydroxylase.InfectionOxygenVirulence

More Related Videos

Methods for Detecting Cytotoxic Amyloids Following Infection of Pulmonary Endothelial Cells by Pseudomonas aeruginosa07:27

Methods for Detecting Cytotoxic Amyloids Following Infection of Pulmonary Endothelial Cells by Pseudomonas aeruginosa

Published on: July 12, 2018

Generation of In-Frame Gene Deletion Mutants in Pseudomonas aeruginosa and Testing for Virulence Attenuation in a Simple Mouse Model of Infection08:34

Generation of In-Frame Gene Deletion Mutants in Pseudomonas aeruginosa and Testing for Virulence Attenuation in a Simple Mouse Model of Infection

Published on: January 8, 2020

Related Concept Videos

Hypoxia01:23

Hypoxia

Hypoxia is a medical condition characterized by an inadequate oxygen supply to body tissues. It typically manifests as a bluish discoloration of the skin and mucosae, especially in fair-skinned individuals, when hemoglobin (Hb) saturation drops below 75%.
Types of Hypoxia
There are four primary types of hypoxia, each resulting from a different cause:
1. Anemic hypoxia: This type occurs due to insufficient oxygen delivery caused by a lack of red blood cells (RBCs) or RBCs with abnormal or...
Pneumonia II: Pathophysiology01:29

Pneumonia II: Pathophysiology

The pathophysiology of pneumonia involves the following steps:
Oxygen Requirements and Growth Patterns01:29

Oxygen Requirements and Growth Patterns

Microorganisms exhibit diverse oxygen requirements and growth patterns driven by their metabolic strategies and environmental adaptations. Oxygen, while essential for many organisms, can also be toxic under certain conditions, shaping how microorganisms grow and survive.Oxygen Requirements of MicroorganismsMicroorganisms are classified based on their ability to use or tolerate oxygen:● Obligate aerobes like Mycobacterium tuberculosis need oxygen for energy production, as it serves as the...
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,...
Determinants of Bacterial Pathogenicity and Virulence01:20

Determinants of Bacterial Pathogenicity and Virulence

Pathogenic bacteria employ a variety of strategies to establish infections, including the secretion of extracellular enzymes that act as potent virulence factors. These enzymes facilitate bacterial colonization of host tissues and help evade immune surveillance. By targeting structural components of host tissues and interfering with immune mechanisms, these enzymes play a pivotal role in disease progression.Extracellular Enzymes Facilitating Tissue Invasion: Several bacterial pathogens secrete...
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...