Scientists Unveil How ‘Conan The Bacterium’ Has Become Resistant To High Doses Of Radiation

Meet Deinococcus radiodurans, a species of bacteria that survived outside the International Space Station for three years and can put the extremes of cold, dehydration, and acidity to shame. Best of all, it can endure radiation 28,000 times greater than human beings. Scientists have naturally given it an equally good nickname—Conan the Bacterium.

Now, scientists have discovered the secret to how the bacterium keeps radiation injuries at bay. The bacterium just needs an antioxidant to protect itself. The researchers believe that they can use the antioxidants to protect humans from radiation on Earth and beyond in the future.

The antioxidant contains phosphate, manganese, and a small peptide (a chain of amino acids). This is basically the holy trinity of a radiation shield, which can shield astronauts from radiation in outer space and the solar system in the future. Study co-author Brian Hoffman recognizes the potency of this radioprotectant, which fares much better than the duo of manganese ions and phosphates.

Brian Hoffman, Michaely Daly, and a group of other scientists discovered that the amount of manganese antioxidants determines how resistant a bacterium is to radiation damage. The greater the amount of manganese antioxidants, the greater the resistance. When dried and frozen, Deinococcus radiodurans can survive 140,000 grays, units of X-ray and gamma-ray radiation.

For the latest research, the team used MDP, or melatonin-derived protective, a type of synthetic antioxidant based on the antioxidant present in ‘Conan the Bacterium’, designed by Daly. The overall structure contains manganese, phosphates, and a peptide called DP1. When together, the trio forms a ternary structure that acts as a radioprotectant. 

MDP can be used in the future to protect astronauts from radiation in deep space, says Daly. Accidents that cause a radiation spillover can be neutralized with the help of MDP. The team’s next mission is to find out if any other bacterium has antioxidants that protect them from radiation.