Researchers have decoded the chemical mechanism behind the extraordinary radiation resistance of Deinococcus radiodurans, a bacterium known as "Conan the Bacterium," according to Interesting Engineering. This microbe continues to astonish the scientific world with its remarkable ability to withstand extreme conditions, including high doses of radiation, acidic environments, cold, and drought.
Brian Hoffman, a chemist from Northwestern University, and Michael Daly from the Uniformed Services University (USU), have uncovered that the resilience of Deinococcus radiodurans is linked to a powerful antioxidant complex composed of manganese, phosphate, and peptides, forming a molecular complex known as MDP with exceptionally strong antioxidant effects, Interesting Engineering reported. "We already knew that manganese and phosphate are strong antioxidants. But discovering the 'magical' effect that emerges with the addition of the third component, peptide, was a major breakthrough," Hoffman stated, according to Interesting Engineering.
The findings of this research were published in the journal Proceedings of the National Academy of Sciences (PNAS). The researchers synthesized an analogue of the powerful antioxidant found in Deinococcus radiodurans and proved that it provides reliable protection to cells from radiation damage, Gazeta.ru reported.
Deinococcus radiodurans can survive extreme doses of radiation, tolerating thousands of times higher radiation than what would kill humans, including up to 25,000 Gray (Gy), Interesting Engineering noted. In dehydrated and frozen states, Deinococcus radiodurans can survive radiation doses of up to 140,000 Gray, which is 28,000 times greater than the lethal dose for humans, as reported by Focus Online.
The bacterium's radiation resistance is attributed to its powerful antioxidant system based on manganese and phosphate that neutralizes toxic oxygen molecules, protecting essential proteins necessary for the cellular repair process, Sozcu explained.
Hoffman and Daly have been studying the bacterium for several years, according to GEO France. In previous work, the researchers studied Deinococcus radiodurans' potential to survive Martian radiation, and in 2022, they published results showing that it can resist the radiation present.
Daly envisions applications to protect astronauts during missions in deep space. "This new understanding could lead to the development of manganese-based stronger antioxidants. These materials, which can be used in many fields such as health, industry, and space exploration, could make a big difference in the future," he said, as reported by Interesting Engineering.
These antioxidants could also protect people on Earth from radiation during nuclear accidents and could be used in preparation for radiation-related emergency situations, Focus Online explained.
The team used advanced paramagnetic resonance spectroscopy to draw the definitive conclusion behind Deinococcus radiodurans' resistance to deadly radiation, and they were able to measure the levels of manganese antioxidants in the cells of the microorganism, Interesting Engineering reported. The synthetic antioxidant was analyzed using electron paramagnetic resonance spectroscopy (EPR) and nuclear magnetic resonance (NMR) techniques, Focus Online noted.
"In tests, the ternary complex protected a protein from radiation doses of up to 60,000 Gray, while a manganese-phosphate complex protected only up to 10,000 Gray," Focus Online reported.
The discovery of MDP has led to the design of new compounds to preserve proteins in vaccines that require sterilization by gamma radiation, Interesting Engineering reported. The researchers engineered a new antioxidant called MDP, inspired by Deinococcus radiodurans' superpower.
This article was written in collaboration with generative AI company Alchemiq