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Updated: Jul 7, 2026
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Replication of the Ordered, Nonredundant Library of Pseudomonas aeruginosa strain PA14 Transposon Insertion Mutants
Published on: May 4, 2018
Dynamics of Pseudomonas aeruginosa genome evolution
Kalai Mathee1, Giri Narasimhan, Camilo Valdes
1Department of Molecular Microbiology and Immunology, College of Medicine, School of Computing and Information Sciences, College of Engineering, Florida International University, Miami, FL 33199, USA.
Summary
Pseudomonas aeruginosa exhibits a mosaic genome, acquiring or losing gene blocks for niche adaptation. This genomic plasticity allows strains to customize their genetic makeup for survival in diverse environments, including human infections.
Area of Science:
- Microbiology
- Genomics
- Evolutionary Biology
Background:
- Pseudomonas aeruginosa is a Gram-negative bacterium known for its adaptability to diverse environments.
- This opportunistic pathogen frequently infects individuals with compromised immune systems or underlying conditions like cystic fibrosis (CF).
Purpose of the Study:
- To perform a complete genome sequencing and comparative analysis of two P. aeruginosa strains isolated from CF patients.
- To understand the genomic basis of P. aeruginosa's adaptability and niche specialization.
Main Methods:
- Whole-genome sequencing of two P. aeruginosa strains from cystic fibrosis patients.
- Comparative genomic analysis against other P. aeruginosa strains.
- Identification and characterization of genomic islands and regions of genomic plasticity.
Main Results:
- P. aeruginosa genomes are mosaic, comprising a conserved core and strain-specific gene blocks located in regions of genomic plasticity.
- A genomic island encoding terpenoid-degrading enzymes was identified in a CF isolate, demonstrating metabolic adaptation.
- Strain-specific genomic segments contribute to enhanced metabolic capacity and environmental adaptation.
Conclusions:
- Niche adaptation, driven by the acquisition and loss of genomic segments, is a key evolutionary force shaping P. aeruginosa genomes.
- Unlike genome reduction in host-adapted pathogens, P. aeruginosa exhibits genome expansion and customization through genomic plasticity.
- This genomic flexibility enables P. aeruginosa to colonize a wide range of environmental reservoirs and cause infections.
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