In Germany, researchers at the Martin Luther University Halle-Wittenberg found that the bacterium called Cupriavidus metallidurans eats up toxic metallic compounds, continues to live and produces tiny gold nuggets as a result. So how do these bacteria manage to eat toxic gold compounds and convert them into the metallic form without harming itself? After studying the why and how since 2009, researchers finally know how the bacterium turn themselves into a gold-producing factory.
Once the gold and copper elements get into the bacterium cells, they interact and get transported deep inside the bacterium where the bacteria employ enzymes to move the toxic metals out of their cells. However, “when gold compounds are also present, the enzyme is suppressed and the toxic copper and gold compounds remain inside the cell,” co-author of the study and microbiologist Dietrich H. Nies told Science Alert. But the bacterium has another enzyme that it releases to get rid of all that unwanted copper which results in tiny gold nugget nanoparticles on the bacterial surface.