(331e) Bisphenol a Degradation and Biofilm Formation By Engineering Shewanella Oneidensis

Bisphenol A (BPA) has been widely used as a plasticizer in the production of synthetic polymers such as food storage containers and feeding/non-returnable bottles. BPA has drawn global attention due to its ability to interfere with endocrine systems, causing carcinogenicity, immunotoxicity, and embryotoxicity. Wastewater treatment bioprocess barely removes BPA due to the poor BPA degradation ability and efficiency of applied microorganisms. Shewanella oneidensis has been studied and a in the biodegradation process of wastewater treatment because of its excellent extracellular electron transfer properties. In this work, we engineered S. oneidensis MR1 to enable BPA degradation. We integrated bisdA and bisdB encoding a BPA degradation pathway from Sphingomonas bisphenolicum AO1 into S. oneidensis MR1. The engineered S. oneidensis MR1 exhibited over 95% of 10 μg/mL BPA degradation within 10 min, while the engineered Escherichia coli with the same BPA degradation pathway showed 80%. Similar BPA degradation percentages were obtained when the BPA concentration was increased to 100 μg/mL. However, high concentrations of BPA was toxic to cells: we observed that 100 μg/mL BPA killed and inhibited the cells after initial BPA degradation. In addition, we improved the biofilm formation of S. oneidensis by enhancing curli biogenesis and c-di-GMP production. Since biofilms are used to degrade toxic organic compounds during wastewater treatment, we study BPA degradation in functional S. oneidensis biofilms. We will discuss the relation between BPA degradation, enhanced electron transfer, and biofilm formation of S. oneidensis.