Unlike most bacteria, however, D. radiodurans contains multiple copies of its genetic material, which can act as backups for each other, Radman says.
Imagine that a cell's DNA holds the message "Humpty Dumpty sat on a wall, Humpty Dumpty had a great fall."
Since the spots where DNA breaks because of radiation or damage are random, each copy of the genetic material will likely have breaks in unique locations.
So if one DNA strand breaks into the split messages "Humpty Dumpty sat on a wall" and "Humpty Dumpty had a great fall," there's likely another chunk of material floating around that can bridge the gap.
The material might read "sat on a wall, Humpty Dumpty," for example.
The bacteria then chemically glue matching pieces together. Once they're bound, the cells fill in the missing parts of each of the two stuck-together copies, the study shows.
Using such clues, D. radiodurans can piece together all of its DNA in about three hours, even if it was split into hundreds of pieces.
"It's true that DNA is life," Radman said.
"As long as you can reconstitute the database of life, which is DNA, you can ... start life again."
The new study "is certainly the biggest advance in understanding the mechanism of radiation resistance" in this well-studied species, said John Battista, a biology professor at Wayne State University in Detroit, Michigan.
Other radiation-resistant microorganisms might use the same mechanism, Battista and Radman agree.
The process could also inspire ideas for repairing our own cells, Radman says.
"It could teach us, maybe one day, how to resurrect dead or close-to-dead neurons [brain cells]," Radman said.
"I joke in the lab that we're going to get a grant from the Vatican titled 'The Molecular Basis of Resurrection.'"
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