Research Area 2: Environmental Remediation: Biomaterials for environmental remediation
Chemicals of concern enter runoff and groundwater, damaging environmental and human health. Some compounds are not removed by conventional water treatment (e.g., perfluorinated alkylated substances (PFAS) and N-nitrosamines such as NDMA), and others are especially toxic (e.g., organophosphate (OP) pesticides), making these compounds especially concerning (Fig 3a). Effective, affordable water treatments are needed to mitigate the impact of these chemicals. We have a platform technology to display enzymes on microbial surfaces. We observe improved protein stability and activity with our scaffolded materials as compared to free protein and can capture or degrade environmental contaminants.
Detecting and degrading OPs. OPs have the same mechanism of action as sarin gas, causing thousands of illnesses and deaths annually. Detection generally involves monitoring degradation products in blood and urine using costly instrumentation. We have engineered a coculture for the simultaneous sensing and remediation of OPs. Engineered electroactive microbes generate current in the presence of OP degradation products and non-viable E. coli surface-express enzymes to degrade OPs (Fig 3b,c). This enables rapid degradation and detection of OPs with 100x higher sensitivity that optical detection for a fraction of the cost.
Figure 3. (a) Contaminants of concern: per- and polyfluoroalkyl substances (PFAS), microplastics, N-nitrosodimethylamine (NDMA), and organophosphate (OP) pesticides. (b) We degrade OPs to p-nitrophenol (p-NP) with surface-expressed enzymes on E. coli. (c) A p-NP-responsive genetic circuit in S. oneidensis generates current with OPs present.