Evolutionary obstacles and not C-F bond strength make PFAS persistent

Area of Science:

• Environmental microbiology
• Biochemistry
• Evolutionary biology

Background:

• Microorganisms are key to degrading environmental organic matter and anthropogenic chemicals.
• Per- and polyfluorinated compounds (PFAS) exhibit resistance to microbial degradation, often attributed to the strong carbon-fluorine (C-F) bond.
• Existing research frequently emphasizes chemical properties over biological factors in PFAS recalcitrance.

Purpose of the Study:

• To reframe the challenge of per- and polyfluorinated compounds (PFAS) biodegradation as a biological optimization problem rooted in evolution.
• To propose an alternative approach to enhancing PFAS biodegradation by focusing on directed evolution of biological systems.
• To challenge the prevailing view that C-F bond strength is the primary impediment to microbial degradation of PFAS.

Main Methods:

• Literature review and synthesis of current research on microbial degradation of chemicals.
• Analysis of the chemical structure and biological interactions of per- and polyfluorinated compounds (PFAS).
• Theoretical framing of biodegradation as an evolutionary and biological optimization challenge.

Main Results:

• Per- and polyfluorinated compounds (PFAS) resistance is better understood as a biological limitation rather than solely a chemical one.
• Recent findings show bacteria capable of degrading multiply fluorinated compounds, indicating biological potential.
• The primary obstacle to efficient PFAS biodegradation lies in biological systems, not inherent chemical stability.

Conclusions:

• The biodegradability of per- and polyfluorinated compounds (PFAS) is best viewed through the lens of biological evolution and optimization.
• Directed evolution of existing microbial C-F cleaving systems presents a more effective strategy than solely seeking new enzymes.
• Further research should concentrate on biological and evolutionary approaches to enhance microbial degradation of persistent fluorinated chemicals.