Toxic Effects of p-Chloroaniline on Cells of Fungus Isaria fumosorosea SP535 and the Role of Cytochrome P450

Efficient methods to remediate PCA (p-chloroaniline)-polluted environments are urgent due to the widespread persistence and toxicity of PCA in the environment. Microbial degradation presents a promising approach for remediating PCA pollution. However, the PCA-degrading fungi still have yet to be explored. This study confirmed the highly PCA-degrading efficiency of an isolated fungus, <i>Isaria fumosorosea</i> SP535. This fungus can achieve a PCA degradation efficiency of 100% under optimal conditions characterized by an initial PCA concentration of 1.0 mM, pH of 7.0 and a temperature of 25 °C. SEM and TEM analyses revealed that the toxicity of PCA resulted in roughened surfaces of <i>Isaria fumosorosea</i> SP535 hyphae, voids in the cytoplasm, and thickened cell walls. PCA addition significantly elevated the activities of cytochrome P450 monooxygenase in both cell-free extracts and microsomal fractions in the media, suggesting the important role of the P450 system in PCA metabolization by <i>Isaria fumosorosea</i> SP535. The results provide a microbial resource and fundamental knowledge for addressing PCA pollution.