Magnetic Nanoparticles in Bacteria

Magnetotactic bacteria produce magnetic nanoparticles with controlled chemical composition, crystal structure, crystal morphology and size. This high level of control is achieved by an intricate biomineralization process occurring in a membrane enclosed compartment, the magnetosome. Additionally, magnetotactic bacteria make use of intracellular filaments to organize these organelles into chainlike structures. This maximizes the magnetic dipole moment of the bacteria and allows the cells to passively align with the field lines of Earth's magnetic field and to actively navigate along them in a process called magnetotaxis in the search for optimal living conditions. The formation of the magnetosome mineral particles and their organization, together with the biological determinants that are involved in these processes are presented in this chapter.