Antibiotic persistence and tolerance: not just one and the same.

Area of Science:

• Microbiology
• Molecular Biology
• Infectious Diseases

Background:

• Antibiotic tolerance and persistence are bacterial survival strategies under antibiotic stress.
• These phenomena are often conflated due to superficial similarities in bacterial survival.

Purpose of the Study:

• To distinguish between antibiotic tolerance and persistence.
• To clarify the underlying molecular mechanisms and experimental approaches for each.
• To evaluate their clinical relevance in bacterial infections.

Main Methods:

• Distinguishing tolerance (population-level, growth-dependent) from persistence (individual-level, transient).
• Analyzing genetic mutations and environmental factors influencing tolerance.
• Reviewing experimental challenges in studying transient persistence.

Main Results:

• Tolerance is a population-level phenomenon linked to growth restriction via mutations or environment.
• Persistence is an individual-level, transient state that is difficult to study.
• Tolerance mechanisms are often studied as a proxy for persistence.

Conclusions:

• Clear experimental differentiation between tolerance and persistence is essential to resolve field controversies.
• Understanding these distinct mechanisms is vital for combating antibiotic recalcitrance and infection relapse.