March 25, 2016

Study finds bacteria that grows more readily in space than on Earth

Well, humans may be struggling to find ways to thrive in outer space, but it seems that bacteria are having no issues—and in fact, one particular species is doing better in space than it does on Earth.

We know all this thanks to a study out of the International Space Station, where microbiologists and members of the public collected samples of Earth bacteria and sent them to the ISS to see how they’d fare in microgravity, according to the study in PeerJ.

Surviving and thriving

Also known as part of Project MECCURI, the study focused on how the bacteria would survive inside the environmental conditions of the space station.

"The warm, humid, oxygen-rich environment of the ISS is a far cry from the vacuum of space," said Dr. David Coil, University of California, Davis, microbiologist and lead author on the study, in a statement.

But microgravity was still an unknown variable. In fact, the bacteria had to be grown on special solid media plates, since liquid media poses a risk in microgravity.

48 different bacterial strains made their way to the ISS. Many bacteria grew at a rate very similar to that on Earth. But one strain in particular was a stand-out: Bacillus safensis. This strain is already well-known to those familiar with the survival of bacteria in space, because its high resistance to UV and gamma radiation seems to have allowed to travel all the way to Mars in 2004, after hitching a ride on the Opportunity and Spirit rovers.

In the study, however, B. safensis didn’t just survive in microgravity—it appears to have grown 60 percent better in space. The current reasons behind this are unknown, but researchers believe that sequencing the genome of the bacteria might yield answers.

"I would love for someone else to follow up the result with Bacillus safensis and see if we could learn more about what happened," said Coil.

But more important than the mystery of B. safensis is the fact that the rest of the bacteria were more or less unaffected by microgravity—something key for planning a long-term piloted spaceflight. For example, bringing bacteria to a non-Earth planet could have devastating effects like we could never have anticipated. Imagine how invasive species have harmed ecosystems on Earth—and then think of something even tougher.

Regardless of the caveats, however, the study has been hugely instrumental in learning more for future space travel.

"The project expands the number of species that have been examined and opens future avenues for research," said Coil.


Image credit: Alex Alexiev/UC Davis, CC BY