Persistence and resistance as complementary bacterial adaptations to antibiotics

Area of Science:

• Microbiology
• Evolutionary Biology
• Genetics

Background:

• Bacterial persistence is phenotypic heterogeneity allowing survival under stress.
• Antibiotic resistance enables growth during antibiotic exposure.
• The relationship between resistance and persistence as evolutionary strategies is unclear.

Purpose of the Study:

• Investigate the co-evolution of antibiotic resistance and persistence in Pseudomonas.
• Determine if resistance and persistence are complementary or alternative adaptations.
• Identify genetic factors influencing persistence.

Main Methods:

• Comparative phylogenetic methods to analyze Pseudomonas strains.
• Assessed intrinsic antibiotic resistance (ciprofloxacin, rifampicin).
• Quantified bacterial persistence following antibiotic exposure.
• Correlated genomic features, including type II toxin-antitoxin systems (TAs), with resistance and persistence.

Main Results:

• Significant variation in antibiotic resistance and persistence across Pseudomonas strains.
• Positive correlation observed between antibiotic resistance and persistence.
• Resistance and persistence are controlled by different genes, indicating independent evolution.
• Type II toxin-antitoxin systems (TAs) correlate with persistence but not resistance.

Conclusions:

• Antibiotic resistance and persistence are complementary but independent evolutionary adaptations.
• Type II toxin-antitoxin systems play a crucial role in the evolution of bacterial persistence.
• Understanding these independent yet complementary traits is vital for combating antibiotic stress.