Deep Bacterium Goes it Alone (broadcast Friday, October 10th, 2008)

The rod-shaped D. audaxviator was recovered from thousands of liters of water collected deep in the Mponeng Mine in South Africa. Micrograph by Greg Wanger, J. Craig Venter Institute, and Gordon Southam, U

Researchers studying a sample of bacteria taken from water in a crack in a South African gold mine -- nearly 3 kilometers below the surface of the Earth -- have found that the ecosystem in the crack consists of only one organism. Writing in the journal Science, the researchers describe a study in which they sampled and sequenced the DNA of organisms found in the crack. Their analysis showed that the bacterium Candidatus Desulforudis audaxviator makes up more than 99.9 percent of the organisms inhabiting the fissure, able to survive without any other organism to feed on, break down, or interact with. In this segment, we'll talk with one of the researchers on the project about the unusual bacterium, which manages to pack all the different processes needed for life into its genome. Teachers, find more information about using Science Friday as a classroom resource in the Kids' Connection.