Contribution

Overview:

Our team focused on dealing the chemical compounds such as PFAS via our engineering bacteria E. coli BL21(DE3), and consequently inspire and motivate water treatment actions, reducing negative effects caused by industrial wastes or some daily necessities.

Parts:

This year, BJWZ-China has made contributions of 2 suceed basic parts, 4 composite parts and 2 biocontainment system. For the composite parts, the team has engineered comprehensive genetic circuits comprising operators, distinct ribosome binding sites (RBS), and signal peptides， linkers, which are designed to enable direct utilization by future iGEM participants. Additionally, a suicidal system derived from BNU-China and BJWZ-China-2024 has been integrated to enhance the biosafety of the engineered system, thereby mitigating the potential risks of genetically modified organisms impacting natural ecosystems.

Hardware:

Focus on practical application

The engineered E. coli-based PFAS detection and degradation system demonstrates multifaceted practical values in real-world applications. In the domain of bioremediation, it targets short-chain PFAS contamination in water bodies and soils (such as accumulation issues in coastal soils), enabling real-time fluorescent warning and degradation initiation via engineered bacteria. By breaking the C-F bonds of PFAS and converting released fluoride ions into calcium fluoride precipitates, this system overcomes the inefficiency of traditional technologies (e.g., activated carbon adsorption and reverse osmosis) in treating short-chain PFAS.
In industrial settings, the system can be integrated into wastewater treatment processes of chemical and manufacturing industries to facilitate online monitoring and in-situ degradation of PFAS-laden effluents. This approach prevents the discharge of high-concentration PFAS (e.g., PFOS) into the environment while reducing the high costs associated with conventional methods like foam separation.
For daily applications, the system safeguards drinking water safety by visually indicating PFAS concentrations through fluorescent signals and achieving synchronous degradation. The arabinose-operon-controlled suicide mechanism of engineered bacteria prevents ecological proliferation, providing a safe and feasible bioremediation solution for small-scale water treatment in households and communities. This integrated technology offers an innovative pathway for cost-effective PFAS management across environmental, industrial, and domestic scenarios.

Purification process

Engineered E. coli BL21-T3 is encapsulated within gel particles (e.g., chitosan-g-polymethacrylic acid) and immobilized in Trough 1. Wastewater containing a defined concentration of PFAS is then passed through the adsorption device at a controlled flow rate, during which PFAS molecules enter the bacterial cells and undergo biodegradation. Following this adsorption treatment, the water flows into Trough 2, which contains a high concentration of calcium chloride, where calcium ions react with fluoride ions to form insoluble calcium fluoride precipitates. Once the water exiting Trough 2 shows no further precipitate formation, it can be directed to downstream reprocessing or discharged in compliance with regulatory standards.

Contribution to the Sustainable Development Goals

Sustainable development is a long and ongoing journey that requires the awareness and active participation of both current and future generations. This project constructs an integrated PFAS (per- and polyfluoroalkyl substances) "detection-degradation" system by engineering Escherichia coli, which is capable of specifically recognizing and degrading PFAS. It reduces the costs of detection and degradation, contributing to solving water pollution issues (corresponding to SDG 6: Clean Water and Sanitation); mitigates the threats of PFAS to human health (related to SDG 3: Good Health and Well-being); prevents the engineered bacteria from leaking through biosafety design, avoiding secondary ecological pollution (in line with SDG 14: Life Below Water and SDG 15: Life on Land); and promotes low-cost bioremediation technologies to drive the sustainable development of the environmental protection industry (responding to SDG 12: Responsible Consumption and Production and SDG 13: Climate Action).We hope that our contribution not only provides a strong foundation for this journey but also helps create a better, more sustainable future that goes beyond the present.