Sharing electrons: An extraordinary friendship between bacteria
Did you know that iron is one of the most important elements on Earth? It is assumed that life evolved close to iron sources. This means that the earliest life forms—and therefore oldest creatures—were able to use iron to obtain energy the way we use food. These tiny organisms are called iron microorganisms and can occur in sediments, which are mainly muddy sand. But less was known about where iron microorganisms live in these sediments—are they located close to the water surface or deep in the sediment? In this study, a team from the University of Tübingen investigated the distribution and variety of iron microorganisms. The scientists discovered that iron microorganisms live independent from their favorite foods: iron, oxygen, and light! This independence might be explained by an unexpected extraordinary friendship with a “living cable.” Are you curious about what a living cable is?