Bioremediation of Arsenic-Contaminated Water Through Application of Bioengineered Shewanella oneidensis

This study aims to determine the bioremediation potential of bioengineered Shewanella oneidensis as a cost-effective alternative for arsenic (As) removal from groundwater, as opposed to the current complex and hazardous chemical and physical methods. Herein we present a novel filtration method, by bioengineering a bacterium with bioremediation potential, S. oneidensis MR-1, to express As-binding protein, ArsR, as it adopts a biofilm lifestyle. The recombinant S. oneidensis (M) was compared to its wild-type MR-1 (WT) across a range of As concentrations (0–800 µM) and time (0–48 h) in its planktonic and biofilm form. Analyses of As-sorption in the wild-type MR-1 and recombinant indicated significant sequestration which increased with time incubated, while As-sorption did not plateau even at high As concentrations of 800 μM. The recombinant displayed significantly higher As sequestration than the wild type (p < 0.0001; cohen’s d = 122.4), with higher sequestration observed in the planktonic compared to the biofilm form (p < 0.0001; cohen’s d = 4.262). Filtration efficiencies of 87% and 94% were obtained for As(III) and As(V) respectively using our system, showing a significant improvement over current commercial systems. With applications in potable water and industrial wastewater filtration, especially for rural and underdeveloped countries given the lack of reliance on specialized equipment, this system represents a powerful potential next-generation Arsenic filtration method.