Bug eats iron, loves acid, lives in California

It eats iron and lives in an environment similar to battery acid. It may also be a major cause of toxic metal and acid runoff.

Not an X-Files episode, but researchers have discovered a super microbe living in a California mine. Published in the journal Science, the report says the microbe is a previously unknown organism that somehow took up residence in the Iron Mountain Mine near Redding, Calif.

Katrina J. Edwards, a geomicrobiologist at Woods Hole Oceanographic Institution and co-author of the study said the microbe gives off sulfuric acid, a chemical that eats into heavy metals and causes deadly concentrations of acid-metal pollution in mine runoff.

The toxic environment in the mine is lethal to most forms of life, according to Edwards. But not for the acid-loving microbe.

Called feroplasma acidarmanus, the microbe is a new species of Archaea a family of microscopic organisms that can live at extreme conditions.

Scientists said the microbe lives best at a level a thousand times more acidic than gastric juices in the human stomach. It also thrives in extremely high temperatures. According to the study, the bug lived off leftover minerals from the mine. It then gives off acid. This leads to a high concentration of dissolved metals that causes the water flowing from the mine to be deadly to other forms of life.

When researchers headed down the mine to collect samples, they had to wear protective clothing. Some suffered burns when water where the microbe lived came into contact with bare skin.

Scientists can't explain how the microbe, not found elsewhere, came to live in the Iron Mountain. But, they said the bug is apparently a major cause of the heavy acid-metal pollution flowing out of the old mine.