Manganese-Munching Microbes

If you've studied chemistry, you may know about manganese, the metal which occupies number 25 on the Periodic Table. Manganese can have good and bad effects. It has negatively affected air quality, groundwater, plants, and the health of humans and some animals. In small amounts, manganese is critical for physiological functions such as enzyme activity, cartilage and bone formation, and blood clotting. However, manganese overdose is very dangerous for humans and animals. If humans receive a large dose of manganese, they may suffer from manganism, a neurological condition characterized by tremors and weakness. Animals may suffer damage to the brain, lungs, liver, and vascular system.

Fortunately, scientists at Caltech have isolated a microbe that can consume manganese and use it for calories! Environmental Science professor Jared Leadbetter made this accidental discovery while he was performing another experiment. He had left a jar with manganese to soak in the sink for a couple of months. When he returned, he noticed an unusual dark material within the jar- microbes. His team wanted to learn more about these microbes. They created cultures, or grew the microbes, and analyzed their genomics and metabolic pathways.

Researchers have previously identified microbes that oxidize manganese, or take electrons from it. However, this is the first time that they have observed manganese chemosynthesis, or when bacteria use this metal to help fuel their physical growth. This discovery may guide bioremediation efforts against manganese pollution - the bacteria can help clean the environment by consuming the metal. This may also help scientists better understand manganese’s path through the nutrient cycle, and how mysterious manganese nodules(spherical objects found on the bottom of the sea) are formed.

Manganese

Picture Source: livescience.com