Exploring a Novel Metallophosphoesterase for Polycarbonate Degradation via Transcriptome Analysis

Polycarbonate (PC), a widely used thermoplastic, poses significant environmental challenges due to its persistence and the release of bisphenol A (BPA), a known xenoestrogen. Here, we report the isolation of Bacillus subtilis JNU01 (BsJNU01), capable of utilizing PC as its sole carbon source. Through transcriptomic analysis, we identified metallophosphoesterase from BsJNU01 (BsMPPE), the first reported metallophosphoesterase capable of degrading polycarbonate by catalyzing the hydrolysis of carbonate ester bonds. This enzyme operates under mild aqueous conditions (30 °C, pH 7), releasing 30 μmol of BPA as a monomer and demonstrating effective PC degradation under environmentally friendly conditions. PC biodegradation was confirmed by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), and gas chromatography-mass spectrometry (GC-MS). Furthermore, surface and mechanical analyses revealed significant degradation and structural changes in PC films following BsMPPE treatment, with toughness showing a 40-70 % decrease compared to untreated PC films. This study represents a breakthrough in microbial plastic degradation, establishing a sustainable biocatalytic platform for PC recycling and upcycling technologies.