A bacterium has been found that has survived in space for a full year.

Living in space for a year is not as easy as it sounds. Scott Kelly, an American astronaut who lived on the ISS for a full year in 2015, underwent changes in his DNA, telomeres and gut microbiome when he returned to Earth. His bone density decreased and he had foot pains for nearly three months after his return. It all happened even when he lived within the ISS protection.

How did bacteria survive in space?

Imagine what would have happened if he had had to survive in the vast space where UV rays, vacuum, large temperature variations and microgravity all pose a serious danger. So, it was naturally no less than a miracle when a species of bacteria that was discovered in a jar of meat was found thriving after a year on a specially designed platform outside the ISS. The bacterium is called Deinococcus radiodurans.

Researchers have been studying the mysterious microbes for some time now. In 2015, a team of international researchers formed the Tanpopo mission where they placed these bacteria outside the Japanese Experimental Module Kibo. Bacteria D. radiodurans it has now shown that it is capable of surviving in vast space. The bacteria cells were shipped to the ISS in a dehydrated state and placed in the exposed facility. It is a kind of platform in constant contact with the environment of space. Here, the cells were placed behind a glass window to block UV light at wavelengths below 190 nm.

The research team from Austria, Japan and Germany wrote in their new article: “The results of this new study may help raise awareness of planetary protection issues on Mars as it absorbs UV rays with wavelengths below 190-200 nm. To generate the same conditions, we installed a silicon dioxide glass window in our experiment on the ISS. ”

Not an attempt to set a record

It wasn’t the only time D. radiodurans he had to survive such difficult conditions. In August of this year, they composed a paper on a sample of the same bacteria kept in space for a period of three years. However, the team wasn’t trying to set a record, they were just trying to understand what makes bacteria adapt to such a harsh environment.

After leaving the bacteria in the presence of intense radiation, varying temperatures and a lack of gravity, the team finally brought the bacteria back to Earth. Then they rehydrated two types of bacteria samples, one that had been on Earth for a year and another that was in Low Earth Orbit (LEO) to compare the results. The bacteria in the LEO had a lower survival rate than its relatives on Earth, but they seemed to be doing well despite some changes.

The team found that the LEO bacterium was enveloped in tiny bumps or vesicles on its surface. It was an indication of the repair systems that had been stimulated and some proteins and mRNAs were in excess. The team isn’t sure how the superficial blisters formed. Such an effort helps us to analyze whether bacteria could survive the journeys between worlds and their environment. The study was published in Microbiome.