Enzymatic depolymerization of polyamides (nylons): current challenges and future directions

• The excessive use of nylon plastics has caused environmental and health impacts. • Enzymatic depolymerization is a promising strategy for recycling waste nylons. • Only a few nylon hydrolases have been identified and characterized so far. • More hydrolases with significant nylon-degrading activity are required. • Several challenges need to be addressed before industrial and environmental use. Environmental accumulation of polyamide (nylon) waste is a pressing global issue. Microbial enzyme-mediated biodegradation serves as the most attractive and eco-friendly approach for the sustainable management of end-of-life nylons. However, it is hampered by inefficient degradation rates and a limited knowledge of potential enzymes and mechanisms. Given its significance, this review aims to provide a comprehensive overview of the advancements in enzymatic nylon depolymerization, their mechanisms, their challenges, and their opportunities. The review can then inform protein engineering and enhance the discovery of novel nylon-degrading enzymes.