Which bacterium is famously known for its extreme resistance to radiation?

The bacterium famously known for its extreme resistance to radiation is Deinococcus radiodurans. It can survive radiation doses that would be fatal to most organisms, as well as severe drying, vacuum, cold, and other stresses. Its toughness has earned it the nickname “Conan the Bacterium.”

The organism’s radioresistance is closely linked to its ability to protect and repair cellular components. It carries multiple copies of its genome and can reassemble chromosomes after radiation causes extensive DNA damage. Its tightly organized DNA and manganese-rich antioxidant systems also help protect proteins from destructive oxidative reactions.

D. radiodurans was originally classified in the genus Micrococcus as Micrococcus radiodurans. Later genetic and biochemical work placed it in its own genus, Deinococcus. The species name combines roots referring to radiation and survival. Although it is exceptionally hardy, it is not a pathogen and does not form endospores. Other organisms, including some Rubrobacter and Chroococcidiopsis species, also show strong radioresistance, but this species remains the classic quiz answer.