Scientists accidentally discover a bacterium that eats metal

Microbiologists at the California Institute of Technology have discovered unusual bacteria that feed on manganese. It is noteworthy that their existence was predicted over a century ago.

Research has shown that bacteria use manganese to convert CO 2 into biomass. This process is called chemosynthesis. Previously, scientists already knew about the existence of bacteria and fungi capable of oxidizing manganese or depriving it of electrons. On this basis, they suggested that there may be unknown microbes that use this process to grow.

One of the research participants, Professor Jared Leadbitter, found chemosynthetic bacteria on a glass jar, which he forgot to wash before leaving, after which it lay for several months before his return.

Leadbitter's attention was drawn to an unusual black coating on the jar, which turned out to be manganese oxide, produced by unknown bacteria, which, apparently, got to its surface with tap water.

Manganese is one of the most abundant chemical elements on Earth. Manganese oxides (MnO2) are a dark lumpy substance found in soil sediments as well as in water distribution systems.

The research results will help to understand the process of formation of special manganese formations - nodules, which cover a significant part of the seabed. These spherical formations, sometimes reaching the size of a grapefruit, were first described in the 70s of the XIX century. In recent years, mining companies have been developing plans for their extraction, as they may contain rare metals.