Three unknown strains of bacteria have been found living in different places in the International Space Station (ISS), researchers have revealed.
The NASA scientists believe that the hardy new bacteria growing on the spacecraft may hold the key to growing crops on Mars.
The the bacteria were found on the surface of the station’s dining table and on an old HEPA filter returned to Earth.
They thought to be related to experiments attempting to grow plants and food on the ISS, ScienceAlert reported.
One strain was identified as Methylorubrum rhodesianum, while the other three were previously undiscovered and belong to a novel species.
Genetic analysis showed them to be closely related to Methylobacterium indicum.
Methylobacterium species are involved in nitrogen fixation, plant growth promotion and biocontrol activity against plant pathogens – which could be useful for growing crops in space.
Dr Kasthuri Venkateswaran (Venkat) and Dr Nitin Kumar Singh, of NASA's Jet Propulsion Laboratory, said that the strains might possess "biotechnologically useful genetic determinants" for growing crops in space.
"To grow plants in extreme places where resources are minimal, isolation of novel microbes that help to promote plant growth under stressful conditions is essential," the researchers said.
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With NASA one day looking to take humans to the surface of Mars, the US National Research Council Decadal Survey recommends that the space agency use the ISS as a "test-bed for surveying microorganisms", according to Dr Venkat and Dr Singh.
"Since our group possess expertise in cultivating microorganisms from extreme niches, we have been tasked by the NASA Space Biology Program to survey the ISS for the presence and persistence of the microorganisms," they said.
"Needless to say, the ISS is a cleanly-maintained extreme environment. Crew safety is the number one priority and hence understanding human/plant pathogens are important, but beneficial microbes like this novel Methylobacterium ajmalii are also needed."
As part of an ongoing surveillance mission, eight locations on the ISS are being monitored for bacterial growths – including where the crew assembles or where experiments are conducted, such as the plant growth chamber.
Approximately 1,000 samples have been collected from various other locations on the space station but are awaiting a trip back to Earth where they can be examined.
According to researchers, the eventual goal is to bypass this lengthy process and potentially find new novel strains using molecular biology equipment developed and demonstrated for the ISS.
"Instead of bringing samples back to Earth for analyses, we need an integrated microbial monitoring system that collect, process, and analyse samples in space using molecular technologies.”
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