Unveiling the mechanisms of metolachlor biodegradation and physiological adaptations in Penicillium oxalicum MetF1.

Environmental risk posed by metolachlor to farmland has garnered significant concern. AlthoughPenicillium oxalicumMetF1 exhibits metolachlor degradation potential, underlying biochemical mechanisms remain unclear. To address this, a comprehensive investigation integrating physicochemical properties, phenotypic characterization, transcriptomic profiling, and metabolomic analysis was conducted. Results demonstrate that MetF1 significantly accelerated metolachlor degradation during the logarithmic growth phase, with only trace metabolites detected. Scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) revealed enhanced phosphorus/sulfur assimilation and metolachlor tolerance, promoting robust microbial growth. Fourier transform infrared spectroscopy (FTIR) further indicated modifications to cellular surface functional groups. Aerobic degradation process involved critical pathways including oxidative phosphorylation, pentose phosphate metabolism, and phenylacetic acid catabolism, mediated by peroxidase, oxygenase, cytochrome P450s, and hydroxylase enzymes. Notably, metolachlor suppressed carbon metabolism while elevating benzene derivatives, suggesting fungal utilization of this herbicide as a growth substrate. This study elucidates the metabolic basis for MetF1-mediated bioremediation of organic pollutants.