Our world is currently being engulfed by the ever growing annual production of plastic waste, and us humans suffer along with the destruction of nature. This prompts us to find a solution to combat this looming threat to humanity, and so we promote PLA product recycling and field-specific degradation.
Plastic pollution is in fact a pressing global issue, and addressing it requires both effective recycling and efficient degradation strategies.
Integrating Human Practice played a vital part in our effort, we eventually targeted our goal through it. Specifically, we promoted sustainability by setting up a target field to prevent plastic contamination, organizing educational events, and submitting a citizen proposal to improve waste management policies.
Later, we identified two main challenges in our iGEM project: current PLA-degrading enzymes exhibit limited activity, and public understanding of plastic classification and disposal is often unclear. To tackle these issues, we adopted a dual approach combining laboratory engineering and community engagement.
In lab, we constructed recombinant genes for Proteinase K (PK), Bacillus licheniformis Alcalase (AC), Candida antarctica Lipase B (CA), and Amycolatopsis sp. PLA Depolymerase (DP). Then, we evaluated their enzymatic activity using pNPB assays. While some enzymes performed slightly better than the GFP control, their activity was generally modest and substrate-specific.
Measurement, aimed to enhance the performances of enzymes, we introduced random mutations to generate variants with potentially higher PLA-degrading capability. Auto-induction was employed to rapidly express and screen multiple variants, enabling efficient testing. Among these, PK variants demonstrated the most significant PLA degradation, becoming the most promising strains in our study.
In SDGs, we aligned our efforts with SDG 4 (Quality Education) and SDG 17 (Partnerships for the Goals) by promoting public education on plastics and submitting a citizen proposal advocating for the establishment of industrial composting systems and clearer waste management policies in Taiwan. In addition, we created a controlled target field where PLA could be used in isolation, preventing contamination with other plastics. Through these activities, we aimed to connect scientific innovation with civic engagement.
Overall, our project demonstrates the potential of enzyme engineering to enhance PLA degradation while highlighting the importance of combining technological solutions with education and policy support. Although further optimization is needed, our findings provide a promising foundation for future strategies in PLA waste reduction and circular bioeconomy applications.