Regional-scale investigation for microbial competition-through-environment interactions modulating antibiotic...

Area of Science:

• Environmental microbiology
• Microbial ecology
• Public health

Background:

• Antibiotic resistance is a significant global health threat driven by microbial competition and various environmental pressures.
• Current strategies to limit antibiotic consumption have shown limited success in controlling resistance.
• The complex interplay between antibiotic-resistant genes (ARGs), microbial communities, and environmental factors necessitates further investigation for effective control.

Purpose of the Study:

• To investigate the relationship between ARGs, microbial communities, and environmental pressures in Yangtze Basin lake sediments.
• To identify potential control pathways for mitigating antibiotic resistance risks.
• To understand how environmental factors influence the evolution and spread of antibiotic resistance.

Main Methods:

• Analysis of surface sediments from 42 lake clusters across the Yangtze Basin.
• Identification and classification of antibiotic-resistant and nonresistant bacterial communities.
• Assessment of environmental parameters, including temperature, salinity, and Mg concentrations, and their correlation with ARGs.
• Modeling the feedback mechanisms between environmental pressures and microbial community dynamics.

Main Results:

• Eleven out of 670 bacterial families were identified as either antibiotic-resistant or nonresistant, exhibiting antagonistic interactions.
• Antagonistic competition within natural systems was found to regulate the abundance of ARGs.
• The dominance of antibiotic-resistant strains led to reduced microbial diversity and increased resistance risk.
• Antibiotics act as a nonlinear orientor shaping ARG evolution, while other environmental factors facilitate resistance.
• Nonresistant communities were found to outcompete resistant ones under specific environmental conditions (temperature, salinity, Mg).

Conclusions:

• Environmental pressures, including temperature, salinity, and Mg, play a crucial role in modulating antibiotic resistance.
• Understanding the chain of links from ARGs to microbial communities and environmental pressures offers a theoretical pathway for resistance risk management.
• Harnessing natural environmental feedbacks presents a potential strategy for controlling antibiotic resistance in aquatic environments.