Abstract: A biologically pure culture of a bacterium of the genus Aquaspirillum, designated MS-1, has been found to contain chains (so-called magnetosomes) of single domain magnetite particles. The magnetite particles are roughly cubic and are about 500 A on a side. Each of the chains contains approximately 20 magnetite particles. These magnetite particles can be recovered from the bacterium and usefully employed in magnetic recording devices and the like. The biologically pure culture of the magnetic bacterium may be grown in a low oxygen environment and on a nutrient medium containing ferric quinate.

Abstract: A biologically pure culture of a bacterium of the genus Aquaspirillum, designated MS-1, has been found to contain chains (so-called magnetosomes) of single domain magnetite particles. The magnetite particles are roughly cubic and are about 500 A on a side and each of the chains contains approximately 290 magnetite particles. These magnetite particles can be recovered from the bacterium and usefully employed in magnetic recording devices and the like.