Discovery of unknown bacterial strains on the International Space Station

In addition to accommodating astronauts, the International Space Station (ISS) also serves as a laboratory for scientific experiments in weightlessness. Among the experiments currently taking place there is an extensive investigation to determine the possibility of growing plants in space.

Understanding how plants behave in such an environment is indeed important for the success of future space missions. On this subject, a team of scientists led by the University of Southern California geneticist Swati Bijlani is studying the presence of microbes on the International Space Station. And an important discovery has just been made.

Enable cultivation in space thanks to microorganisms

Science Alert informs us that four strains of bacteria were discovered on board the vehicle. Three of them are completely new. Sure, this information might startle some of us, but they know that scientists consider it excellent news.

The presence of these microorganisms actually means that we should be able to grow plants in an alien world. They were also discovered on board the station because the astronauts were already cultivating plants there.

Three completely new bacteria

Contrary to what some of us might think, the identified tribes are therefore not of extraterrestrial origin. In their report, published March 15 in the journal Frontier in Microbiology, the researchers point out that this family of bacteria lives primarily in soil and freshwater.

According to the study, one strain that was harvested on a HEPA filter at the station belongs to a family known as Methylorubrum rhodesianum, while the other three entirely new strains were named IF7SW-B2T, IIF1SW-B5, and IIF4SW-B5. However, further analysis has shown that these are linked to a bacterium called Methylobacterium indicum.

Three of the four strains were isolated in 2015 and 2016 – one was found on a hanging board from ISS research stations, the second in a module, the third on the surface of the dining table, and the fourth in an old HEPA filter returned to Earth in 2011 back. Photo credit: Shutterstock / Design Projects

A very promising variety

Genetic analysis has shown that the strain IF7SW-B2T is the strain most likely to support plant growth in an extraterrestrial environment. It contains promising genes, including one linked to an enzyme essential for cytokinins.

“In order to grow plants in extreme locations with scarce resources, it is important to isolate new microbes that encourage plant growth in stressful conditions,” said two team members, Kasthuri Venkateswaran and Kumar Singh of JPL of Nitin NASA, in a press release.

The latter is actually a substance that promotes cell division in roots and sprouts. More in-depth studies are needed to confirm this. In fact, the team plans to analyze around 1,000 more samples collected from the ISS. On January 15, 1998, the crew of the Mir space station discovered a floating ball of liquid filled with microorganisms when they opened a seldom used service panel.