Fungi onboard ISS survives high doses of ionizing radiation

Posted Jul 18, 2019 by Tim Sandle
New research presented at the 2019 Astrobiology Science Conference shows that mold on the International Space Station is capable of surviving high doses of ionizing radiation. This finding is important for future deep space missions.
The International Space Station is featured in this image photographed by an STS-133 crew member on ...
The International Space Station is featured in this image photographed by an STS-133 crew member on space shuttle Discovery after the station and shuttle began their post-undocking relative separation. Undocking of the two spacecraft occurred at 7 a.m. (EST) on March 7, 2011
Courtesy NASA
Fungi are found everywhere on Earth and there could be up to 1.5 million different species (this is difficult to estimate, given that only around 150,000 have been genetically characterized). One thing is for certain, fungi are associated with human habitats, and this extends beyond being Earth-bound. One of the environmental issues with the International Space Station (ISS) is the levels of indoor mold and the astronauts need to invest time every week or so cleaning and disinfecting the space inside (a necessary step to reduce allergies being triggered).
The new research suggests that fungi can also survive (at least phonetically) on the outside on the space station, being immune to the harsh effects of space, including bombardment with radiation. This means that fungal spores could, perhaps, be transported from Earth to Mars.
To understand if fungal spores are able to survive space travel, typical species common to Earth and in relation to what has been recovered from the space station were exposed to different kinds of radiation: ultraviolet, X-ray and heavy ions.
Research conducted by Dr. Marta Cortesão, a microbiologist at the German Aerospace Center (DLR) in Cologne has found that two genus of fungi, common to most habitats in Earth, survive X-ray exposure at 200 times the dose that would kill a human. These are the genus Aspergillus and Pennicillium. While not often harmful, both fungal groups can pose a risk to an immunocompromised person.
Based on the study, Cortesao said: "If we're planning a long duration mission, we can plan on having these mold spores with us because probably they will survive the space travel."
Fungi in space hold the possibility of doing good as well as causing harm. Filamentous fungi can produce important compounds like antibiotics and vitamins. However, the same organisms can be human pathogens and a food spoilers. They can also it also can be used to produce antibiotics.
The findings were presented at 019 Astrobiology Science Conference in Bellevue, Wa., U.S.