Biodegradation of Pendimethalin by Paracoccus sp. P13

Area of Science:

• Environmental microbiology
• Bioremediation
• Pesticide degradation

Background:

• Pendimethalin is a widely used herbicide in agriculture.
• Effective and sustainable methods for pendimethalin removal from the environment are needed.
• Microbial degradation offers a promising approach for pesticide remediation.

Purpose of the Study:

• To isolate and identify microorganisms capable of degrading pendimethalin.
• To investigate the efficiency and optimal conditions for pendimethalin degradation by the isolated strain.
• To elucidate the initial steps of the microbial pendimethalin degradation pathway.

Main Methods:

• Isolation of pendimethalin-degrading bacteria from contaminated soil.
• Identification of the bacterial isolate using morphological, physiological, and 16S rRNA gene sequencing.
• Quantification of pendimethalin degradation using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS).
• Determination of optimal pH and temperature for degradation.

Main Results:

• A bacterial strain, identified as Paracoccus sp. P13, was isolated.
• Paracoccus sp. P13 efficiently degraded 100 mg/L pendimethalin within 2 days and 200 mg/L within 5 days.
• The degradation pathway was proposed to involve oxidation ring cleavage, yielding an alkane organic intermediate, ultimately producing CO2 and H2O.
• Optimal degradation occurred at pH 7.0 and 30°C.

Conclusions:

• Paracoccus sp. P13 is a highly efficient pendimethalin-degrading bacterium.
• This study presents a novel microbial pathway for pendimethalin degradation.
• The findings suggest potential applications for Paracoccus sp. P13 in the bioremediation of pendimethalin-contaminated environments.