Engineered Magneto-Receptive E. coli

Naturally occurring magnetotactic bacteria have an inherent ability to sense and align to earth's geomagnetic field due to the presence of magnetosomes-membranous microstructures containing iron oxide nanoparticles. These functionalities can be exploited for tuning movements and guided spatial patterning in controlled magnetic field. While being arduous to culture in laboratories, these organisms have complex genetic make-up with tight regulation on their magnetosome synthesis. Inspired by the magnetotactic bacteria, we aim to render magnetic behavior to E. coli. We mimic the magnetosomes in magnetotactic bacteria by employing a membraneless proteinaceous compartment from the thermophilic iron storage protein, ferritin, fused with a magnetite-forming peptide, m6A. To enhance iron accumulation, the E. coli iron metabolism is engineered by tailoring the expression of iron influx and efflux genes. Numerical simulations support our observations of a highly responsive magnetic E. coli. This study presents a strategy to engineer magnetic response in E. coli which can be adopted to other bacteria.