Engineering biofilms for efficient removal of arsenic from water

One of the most fundamental necessity for mankind – clean water, is gradually decreasing as the world population increases beyond 7 billion. Arsenic contaminated groundwater is one of the main concerns, given its carcinogenic nature and widespread in waterbodies across the world. Various methods has been developed for arsenic removal, however, the application of these technologies is more often than not beyond the capacity of developing nations. In light of this, a research on the Shewanella oneidensis MR-1 strain was conducted to explore the feasibility of bacterial sorption of groundwater arsenic for the cleansing of water. S. oneidensis is a bacterium known for its functional protein, BpfA, which promotes the growth of biofilm. The innate ability of S. oneidensis to form biofilm for the sorption of arsenic is a more affordable method, however there is a threshold concentration limit to the extent of sorption. Hence, we explore the viability of modifying the genetics of the bacterium to enhance its sorption capacity. A mutant, BK3, was genetically-modified to express functional peptide for arsenic sorption on cell surface and was experimented in comparison with the wild type to differentiate their biofilm formation performance. In this report, the performance of wild type and BK3 in their biofilm and planktonic states will be discussed to determine the optimal conditions for sorption, and thus removal of arsenic.Bachelor of Engineering (Environmental Engineering