Identification of a PET hydrolytic enzyme from the human gut microbiome unveils potential plastic biodegradation in human digestive tract

Widespread use of polyethylene terephthalate (PET) plastics and their recycling challenges have led to substantial accumulation of PET wastes in global environments, with inevitable consequences for their entry into the food chains. Recent studies have increasingly documented the ingestion of microplastics by humans through food and beverages. However, the fate of these microplastics within the gastrointestinal tract, particularly the role of the human gut microbiota, remains inadequately understood. To address this knowledge gap, we employed a bioinformatics workflow integrated with functional verification to investigate the PET digestion/degradation capabilities of intestinal microorganisms. This approach identified a novel PET hydrolase-HGMP01 from the human gut metagenome, which exhibits the capacity to hydrolyze PET nanoparticles. Moreover, comprehensive exploration for HGMP01 homologues in the human gut metagenome and metatranscriptome unveil their distribution in diverse intestinal microorganisms. This study provides biochemical evidence for an unforeseen role of human gut microbiome in plastic digestion, thus holding substantial implications for human health.