NASA astronomers have finally identified three unknown microbes found hitching a ride on the International Space Station without sending the samples to Earth for analysis.
Which microbes are hitching a ride on the ISS?
Spoiler: it’s not aliens. However, astronomers were still able to clear a significant hurdle, which is being able to do successful gene sequencing aboard the the ISS itself. This effort was part of an experimental campaign called Genes in Space-3, a collaborative project that seeks to identify unknown microorganisms found in space. The project wanted to be able to achieve their goals without having to send their samples to Earth for identification.
How do you culture and sequence bacteria on the ISS?
This year, these goals became a reality. A new study details how researchers were able to complete the process from sample to sequencing right on board the ISS for the first time ever. The success of this project could lead to the ability to diagnose illnesses in astronauts in real time right on the space station.
Of course, doing something as groundbreaking as this for the first time is difficult. The handheld MiniON sequencer by Oxford Nanopore Technologies teamed up with a DNA replicator that facilitates a polymerase chain reaction, or PCR. Researchers made copies of the microbes’ DNA using a device called miniPCR, which were studied to determine the what exactly the mysterious microbes were.
NASA’s Peggy Whitson collected bacteria samples by touching petri dishes to various spots on the ISS. Cultivation of the bacterial colonies took about a week, before Whitson transferred the colonies to the Microgravity Science Glovebox on the station.
The Johnson Space Center [Photo by NASA]
However, while PCR amplification was taking place up on the ISS, Hurricane Harvey was battering Texas. Because of this, the Johnson Space Center wasn’t able to communicate with Whitson to talk her through the process of identifying the microbes. Luckily, Genes in Space-3 coordinator Sarah Wallace was able to reach Whitson through a cell phone and and guide her in putting the microbes through the sequencer.
The resulting sequencing enabled the researchers to figure out the exact order of nucleotides on the DNA, which in turn let them identify the microbes. The pairing of the miniPCR and the MiniON allowed the researchers to “take the lab to the samples, instead of us having to bring the samples to the lab,” says NASA biochemist Aaron Burton.
Researchers were eventually able to send the sample back to Earth, where researchers were able to verify the findings to be accurate.
Get weekly science updates in your inbox!