Integrated omics analyses elucidate acetaminophen biodegradation by Enterobacter sp. APAP_BS8

Acetaminophen (APAP) is an extensively consumed over-the-counter and prescribed medication and a constituent of many active pharmaceutical compounds as well as personal care products. Its wide-scale prevalence in the environment due to inefficient treatment technologies has classified APAP as a contaminant of emerging concern. Thus, it is imperative to explore efficient and sustainable methods for remediation of contaminated environments. Considering the need for potent microbial resources, the present study deals with the evaluation of Enterobacter sp. APAP_BS8, degrading ∼88% of APAP (300 mg kg^-1) in 16 days in microcosms, and accomplishes the mechanistic perspectives of degradation through in-depth insights into genomics, proteomics, and metabolomics. Whole genome analysis of the 4.9 Mbp genome sequence revealed deaminated glutathione amidase, glucosamine-6-phosphate deaminase, LLM class flavin-dependent oxidoreductase, and oxidoreductase genes can mediate the degradation. Increased expression of proteins corresponding to these genes was observed in proteome analysis. Molecular docking and simulations presented operative interaction and binding of the degradation pathway intermediates at the catalytic site of the identified enzymes. Analysis of the metabolome identified hydroxyquinol, 4-aminophenol, and 3-hydroxy-cis, cis-muconate as intermediates. The outcomes revealed that Enterobacter sp. APAP_BS8 exhibits potential enzymatic machinery for APAP degradation, thus providing scope for formulating sustainable bioremediation technologies.