When most people think of the microbiology of the built environment they think of pathogens that hang out in buildings.
Here’s a neat story about a helpful bacteria that lives in a very different kind of “built environment”… a uranium mill tailings site. These tailings facilities are where all the waste and excess rock from a uranium mine are kept. The facilities need to be maintained for thousands of years to prevent contamination of the surrounding environment.
However, even in this harsh environment we find several kinds of microbes and in this case a type called Geobacter sulfurreducens is actually reducing the uranium. This doesn’t eliminate the radioactivity, but it does immobilize the uranium which prevents it from leaching into groundwater. Very handy. Also useful for cases where uranium has already leaked into the water supply.
Anyway this recent report in PNAS (not open access) details the finding that this reduction activity takes place on the conductive pili on the surface of the bacterial cells. The authors also discuss the fact that these conductive pili have potential to generate electricity in a microbial fuel cell.
So in theory, there’s potential here to generate electricity, while simultaneously cleaning up polluted sites and preventing further groundwater contamination. Pretty cool.