Omics-centric evidences of fipronil biodegradation by Rhodococcus sp. FIP_B3.

Area of Science:

• Environmental Science
• Microbiology
• Biotechnology

Background:

• Widespread fipronil pesticide use leads to environmental accumulation, impacting soil health and human well-being.
• Microbial degradation offers a promising strategy for removing persistent fipronil residues from contaminated environments.

Purpose of the Study:

• To investigate the omics-based biodegradation of fipronil by the native bacterium Rhodococcus sp. FIP_B3.
• To elucidate the key enzymes, metabolites, and molecular mechanisms involved in fipronil degradation.

Main Methods:

• Utilized an omics approach, including whole genome analysis, for Rhodococcus sp. FIP_B3.
• Identified major biodegradation metabolites and employed in-silico molecular docking and dynamic simulations.
• Quantified degradation kinetics and half-life of fipronil.

Main Results:

• Rhodococcus sp. FIP_B3 achieved 84% fipronil degradation within 40 days, following pseudo-first-order kinetics (k = 0.0197/d, half-life ~11 days).
• Identified key enzymes (e.g., Cytochrome P450 monooxygenase, haloalkane dehalogenase) and major metabolites (e.g., fipronil-sulfone, trifluoropropanoic acid).
• In-silico analyses confirmed stable interactions between intermediates and enzymes, with binding energies ranging from -5.9 to -9.7 kcal/mol.

Conclusions:

• Rhodococcus sp. FIP_B3 exhibits significant potential for fipronil biodegradation.
• The identified mechanistic insights are crucial for developing effective bioremediation strategies for fipronil-contaminated ecosystems.