Antibiotics regulate bacterial diversification, niche expansion and evolution under primordial conditions

Area of Science:

• Origin of Life Studies
• Microbial Ecology
• Astrobiology

Background:

• Bioactive small molecules and life's building blocks co-emerge in early Earth chemical networks.
• The role of these molecules in primordial microorganism evolution is critical but understudied.
• Monopolization effects in early microbial communities shape energetic metabolisms.

Purpose of the Study:

• Investigate the impact of antibiotics on bacterial evolution in a simulated primordial environment.
• Determine if antibiotics influence energy source production and niche expansion.
• Assess the role of antibiotics in microbial community stability and adaptation.

Main Methods:

• Enrichment of bacterial communities with early energetic metabolisms from groundwater.
• Exposure of enriched communities to tetracycline, penicillin, and chloramphenicol.
• Analysis of bacterial responses, including energy source production and phenotypical changes.

Main Results:

• Antibiotics counteract monopolization by stimulating diverse energy sources (sulfide, acetate, nitrate, sulfate).
• Antibiotic exposure promotes bacterial niche expansion and adaptation to new energy sources.
• Tetracycline may enhance diversity disparity, stabilizing the micro-ecosystem; antibiotics drive phenotypical differentiation.

Conclusions:

• Antibiotics, co-generated with life's building blocks, act as an evolutionary force.
• They drive diversification, niche expansion, and ecosystem stability in primordial microorganisms.
• Antibiotics promote adaptation and counteract monopolization in early life forms.