A myriad micro organisms on our planet’s surface – and especially subsurface – live in the harshest, most extreme environments.  Boundary conditions have been pushed in every possible direction, encompassing broad swaths of temperature, pH, pressure, radiation, salinity, energy, and nutrient limitation. Their metabolic activity depends on their ability to acquire and eventually feed off metal ions. Over billions of years microorganisms have evolved and perfected their repertoire of molecular solutions to metal separation problems.