Investigation into the Metabolism of Quaternary Ammonium Compound Disinfectants by Bacteria

Since the start of the COVID-19 pandemic, our reliance on disinfectants and sanitizers and the use thereof has grown. While this may protect human health, it may be selecting for antimicrobial-resistant microorganisms, including those that are not only capable of growth in the presence of disinfectants but also thrive using this as an energy source. Furthermore, there is a growing concern in emerging nosocomial pathogens, which have shown resistance to antibiotics and disinfectants. This rise in resistance has led to the investigation of various mechanisms behind resistance, such as biofilms, efflux pumps, and mobile genetic elements. Although many resistance mechanisms have been identified, it was discovered that some potentially pathogenic microbes could metabolize these compounds, which remains an avenue for further investigation. Investigating alternative metabolic pathways in microorganisms capable of growth using disinfectants as their sole carbon and energy source may provide insight into the metabolism of quaternary ammonium compound (QAC)-based antimicrobials. Many of the metabolic reactions proposed include hydroxylation, N-dealkylation, N-demethylation, and β-oxidation of QACs. If clear metabolic pathways and reactions are elucidated, possible alternative approaches to QACs may be advised. Alternatively, this may provide opportunities for biodegradation of the compounds that adversely affect the environment.