Transformation products of antibiotics: overlooked drivers for enhancing the environmental spread of antibiotic resistance

Abstract

Humans have released thousands of antibiotics into the environment, which is a primary driver of the global dissemination of bacterial resistance. Parent compounds can generate various transformation products (TPs), many of which remain unidentified and lack comprehensive microbial risk assessments. The TPs formed during the process may exhibit structural similarities to the parent compounds, and they can induce antibiotic-like resistance transmission despite lacking the bactericidal/antibacterial properties of the parent compounds. However, assessments of antimicrobial resistance hazards predominantly emphasize parent compounds while largely neglecting their TPs. Here, we highlight that TPs warrant greater attention regarding chemical structure identification and the risk of resistance transmission. This perspective summarizes TPs’ potential, mechanisms, and challenges in triggering the risk of resistance transmission.

Keywords

Antibiotic resistance / transformation products / resistance transmission / horizontal gene transfer / antibiotic-like effects

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