Abstract

Exposure to cadmium, a heavy metal commonly used in industrial processes, causes serious health problems including kidney disease, lung damage, bone fragility, cancer, infertility, and death. There is significant demand for the effective bioremediation of cadmium in developing countries and in industrial regions. Current methods are expensive and often produce undesired byproducts. This project aims to engineer a strain of magnetotactic bacteria known as Magnetospirillum magneticum AMB-1 for biosorption of cadmium.

AMB-1 is a strain of magnetotactic bacteria that aligns to magnetic fields with magnetite-accumulating organelles. This strain has been identified as a suitable chassis as it can be isolated with magnetic forces and may carry a heavy metal transporter that could result in natural cadmium tolerance. A metal transporter gene native to magnetotactic strains (mntH) and a S-adenosyl-methionine-dependent methyltransferase (smtA) derived from E. coli were incorporated into a genetic circuit designed to maximize biosorption and cadmium tolerance. AMB-1 carrying this design on a shuttle vector plasmid was tested for bioremediation efficiency.