Potential plastic biodegradation in lakes worldwide

Area of Science:

• Environmental Microbiology
• Biotechnology
• Genomics

Background:

• Plastic pollution is a pervasive global issue, with limited understanding of microbial capabilities for plastic biodegradation.
• The distribution and potential of plastic-degrading microbes in natural environments remain largely unexplored.

Purpose of the Study:

• To investigate the global distribution of plastic-degrading potential in lake ecosystems.
• To identify and characterize novel plastic-degrading bacteria and enzymes for bioremediation applications.
• To develop a computational framework for assessing microbial degradation potential and a method for enriching target communities.

Main Methods:

• Integrated metagenomic and machine learning analyses of 182,661 global lakes.
• Construction of a comprehensive catalog of plastic-degrading bacterial enzymes and genomes.
• Development of a computational categorization system for candidate plastic-degrading bacteria.
• Customization of culture media and isolation of plastic-degrading microbial strains.

Main Results:

• Identified a tipping point (≥7.44 particles/m³ ) for effective in situ bioremediation.
• Cataloged 15,715 enzyme homologs and 4,856 metagenome-assembled genomes.
• Developed a computational approach to categorize bacteria by degradation potential, ecological risk, and adaptation.
• Successfully enriched plastic-degrading communities and isolated *Serratia ficaria* HfyG-1, capable of degrading polylactic acid and polyethylene terephthalate.

Conclusions:

• Plastic waste significantly influences the global distribution of microbial plastic-degrading potential.
• The study provides a valuable molecular resource and a proof-of-concept framework for identifying and utilizing microorganisms in plastic bioremediation.
• The isolated strain *Serratia ficaria* HfyG-1 demonstrates significant potential for degrading common plastics like polylactic acid and polyethylene terephthalate.