MrSeb writes: "In the future, ultra-high-density non-volatile storage — such as hard drives — could be grown using magnetic bacteria. This breakthrough, shepherded by researchers from the University of Leeds in the UK and the Tokyo University of Agriculture and Technology, relies on certain strains of bacteria that ingest iron, which is then converted into magnetite (iron (II, III) oxide). These microbes, by following the Earth’s magnetic field, then use this built-in magnet to navigate. To turn this behavior into something that can actually act as magnetic storage, the researchers identified and extracted the protein responsible for converting iron into magnetite — Mms6. A gold substrate is then covered in a checkerboard fashion with chemicals that bind to Mms6, and the substrate is dunked in the protein. The whole caboodle is then washed with an iron solution, turning each of the Mms6 sites into a magnetic bit. For now the researchers have only managed to create magnetic bits that are 20 micrometers wide, which equates to 20,000 nanometers — a wee bit larger than the 10nm magnetic sites found on modern hard drives, but the researchers seem confident that 20nm magnetic sites should be possible."