Spore forming bacterium are notoriously resistant to most ways of killing them. There's even a species that can resist radiation amounts that are 1000x the dose needed to kill a human.
I want this mutation. You have little nano-crawlers going up and down your DNA strands fixing problems. It’s like ECC RAM for the essence of YOU. And you’re basically immune to cancer.
Deinococcus radiodurans has a unique quality in which it can repair both single- and double-stranded DNA. When damage is apparent to the cell, it brings the damaged DNA into a compartmental ring-like structure where the DNA is repaired, and then is able to fuse the nucleoids from the outside of the compartment with the damaged DNA.