For many years, scientists have been conducting studies at the International Space Station (ISS) to determine the effects of living in space on humans and microorganisms. In addition to high levels of radiation, there is also concern that prolonged exposure to microgravity can lead to genetic mutations. Understanding these and accepting countermeasures is essential if we want humanity to become a true space species.
Interestingly, a group of researchers from the Northwestern University recently conducted a study on bacteria that was on board the ISS. Contrary to what many assumed, the bacteria did not mutate into a super-resistant super-strain, but they were struggling to adapt to their environment. These results can be essential to understanding how living beings will adapt to the stressful environment of the space.
A study that describes the findings of the group has recently appeared in mSystems, a scientific journal that he published American Association for Microbiology. The research was led by Erica Hartmann, assistant professor at the Department of Civil and Environmental Engineering (DCEE) at the NWU, and included many DCEE postgraduate and postdoctoral researchers and Sarah Castro-Wallace from NASA Johnson Space Center.
Such studies are essential for missions planned in the near future, including the NASA plan for renewed missions to the surface of the Moon and their proposed mission on Mars. In addition, China, Russia and India are also planning to send astronauts to the moon in the coming decades. As Professor Hartmann explained in the press release NWU:
"There has been much speculation about radiation, microgravity and lack of ventilation and how this could affect living organisms, including bacteria. These are stressful, difficult conditions. Does the environment choose for superchargers because they have the advantage? It seems that the answer is "no".
Because of their study, Hartmann and colleagues provided data from the National Biotechnological Information Center (NCBI), which maintains archival information on microbial experiments carried out on the ISS. More specifically, they assessed how the bacterial strains of Staphylococcus aureus and Bacillus cereus grew in space.
The first one is located on the human skin and contains the healing resistant strain MRSA, which makes it responsible for several infections that are difficult to treat in humans. The latter lives in the ground and has few consequences for human health, but still provides valuable information on how the land microbes grow when they are removed from their comfort zone and subject to unfamiliar space conditions.
"Bacteria that live on the skin are very pleased there," said Hartmann. "Your skin is warm and contains some oils and organic chemicals that bacteria really adore. When you lose these bacteria, they find themselves in a very different environment. The building's surface is cold and clumsy, which is extremely stressful for some bacteria. «
When the team compared how these strains grew on the ISS, how they grow the same species on Earth. They found that bacteria living on the ISS mutated to adapt to local conditions, choosing favorable genes in order to continue eating, growing and acting in microgravity and exposure to higher levels of radiation.
Ryan Blaustein, a postdoctoral associate at Laboratory Hartmann, who was the first author of the study, showed that this was a surprising result. "Based on the analysis of genomes, bacteria appear to be adapting to life – they do not develop to cause disease," he said. "In the bacteria of the space station, we have not seen anything special about antibiotic resistance or virulence."
This is certainly good news for future astronauts, not to mention people who hope to once participate in the growing space of space tourism. In both cases, crews are forced to live, work, and usually tolerate time in small capsules or modules, where there is no ventilation, and air circulates for a long time.
Given the health risk, there is awareness that land bacteria will not mutate into super-calls that are even more resistant to antibiotics, certainly relief. Of course, Hartmann and her colleagues stressed that this study does not mean that microbes can not reproduce when they come to a spacecraft or a space station:
"Wherever you go, you bring microbes with you. Astronauts are extremely healthy people. But when we talk about the expansion of space flights to tourists who do not necessarily meet the criteria of astronauts, we do not know what will happen. We can not say that if someone who has an infection is placed in a closed bubble in the universe, he will not be transferred to other people. It's the same when someone coughs on a plane and everyone gets sick. "
As always, space exploration poses a great danger and the ability to send astronauts to longer trips or tourists into space presents many challenges. Fortunately, we have decades of research that we can rely on and a lot of top-notch experiments that help us to get information before this day comes.
This study was supported by the support provided by the Searle Leadership Fund and the National Institute of Health (NIH).
Further reading: Northwestern University, mSystems