In the event of a nuclear accident or blast, humans can be exposed to ionizing radiation that causes cancer and heart disease, among other problems. But now a group of scientists have bred a strain of bacteria that can repair its own radiation damage. This has implications for us, too.
One of the ways that radiation causes illness is by damaging our DNA. University of Wisconsin-Madison biochemist Michael Cox and his team wanted to find out whether they could breed the common bacteria E. coli to be more resistant to radiation damage. So they took a group of E. coli, bombarded it with radiation until 99 percent of the microbes were dead, and then bred a new generation from the survivors. After 20 rounds of this, they wound up with a group of E. coli that could repair radiation damage after being blasted with ionizing radiation that was four orders of magnitude greater than what their ancestors could endure.
In a new study, published earlier this month in the journal eLife, Cox and his team analyzed the 69 known mutations that allowed these E. coli to be so good at repairing themselves after intensive radiation bombardment. Our bodies repair DNA in many of the same ways that bacteria does. So this study sheds light on ways that human cells could one day repair radiation damage too.
Said Cox in a release, "What our work shows is that the [DNA] repair systems can adapt and those adaptations contribute a lot to radiation resistance."
It seems that Cox and his team's E. coli are actively repairing their DNA in the wake of radiation damage. But of course, there are a lot of unknowns here. "This extreme resistance we're looking at is a complicated phenotype," added Cox. "There are likely additional mechanisms buried in this data and we're working to pull those out."
If we can figure out how the E. coli are repairing themselves, we could one day possibly use gene therapy to make humans more resistant to radiation. This could help people undergoing radiation therapy and could lead to the development of bacteria engineered to clean up radioactive wastes in the event of disasters like those at the Fukushima reactor.
It's also possible that this research could help future astronauts and colonists on other worlds where there is more radiation bombardment from space.
Read the full scientific study in eLife