It is an almost indestructible bacterium.
Deinococcus radiodurans, nicknamed "Conan the Bacterium," withstands levels of radiation that would destroy any organism on Earth. How does it manage to survive under such conditions? Scientists have finally uncovered its secret.
Capable of tolerating up to 140,000 grays of radiation, this bacterium exhibits a resilience that is almost unbelievable. In comparison, a dose of 5 grays is enough to kill a human. Recent studies have shown that this extreme robustness is based on a simple yet highly effective mechanism: a unique antioxidant complex.
Scientists believe that "Conan the Bacterium" (photo) could survive for 280 million years on Mars, if buried underground.
This complex, named MDP, combines three key elements: manganese ions, phosphate, and a small peptide. This "ternary complex" acts as a true shield against the destructive effects of radiation. Researchers from Northwestern University and the Uniformed Services University confirmed that these three components, when combined, protect cells far better than when used individually.
To uncover this mechanism, the team employed advanced spectroscopy techniques. These analyses revealed that the resistance of
Deinococcus radiodurans is directly linked to the abundant presence of manganese-based antioxidants in its cells. The higher their concentration, the more the bacterium can withstand radiation.
This discovery opens up astonishing possibilities. By mimicking the function of MDP, researchers have developed a synthetic antioxidant. This could be used to protect astronauts exposed to cosmic radiation during space missions. Indeed, beyond Earth's atmosphere, solar and galactic radiation pose a constant threat to living organisms.
The potential applications aren't limited to space. The healthcare industry could use these antioxidants to develop new treatments. For example, they could protect human cells from damage caused by radiation in medicine or during nuclear accidents.
Another promising field: the production of inactivated vaccines. Irradiation can destroy pathogens while preserving their structure. This approach, facilitated by MDP, could make vaccines more effective and safer.
Scientists do not rule out the possibility of applications on Mars. Previous studies had already shown that
Deinococcus radiodurans could survive beneath the Martian surface. This discovery strengthens the hypothesis that microbial life forms could exist on the Red Planet.
Thus, the study of this extreme bacterium offers much more than mere scientific curiosity. It paves the way for a future where natural survival mechanisms could inspire crucial innovations in space exploration and the protection of humanity from radiation.
Article author: Cédric DEPOND