NASA astronauts conducted the successful sequencing of the DNA of microbes that are present on the International Space Station. The event marks the first instance when the sequencing and identification of unknown microbes were entirely carried out in space.
The ISS crew members discovered that the mysterious organisms were two microbes commonly linked with the human microbiome. Before this event, microbes were generally sent back to the planet for analysis.
The new sequencing event marks not only a significant step toward the diagnosis of illnesses of astronauts but also paves the way to identify any life based on DNA on other extraterrestrial worlds.
Ground-based researchers further verified the correctness of the organism identifications, which marked the success of the ISS-based experiment.
A Successful Experiment Conducted In Space
ISS astronauts touched a petri plate to the space station’s surface last year and cultivated the bacteria collected there into colonies. ISS crew member Peggy Whitson amplified and subsequently sequenced the DNA of the cultivated bacteria.
In July last year, crew member Kate Rubins was the first person to conduct DNA sequencing in space. The latest experiment was, however, the first instance of transferring the cells for observation and identifying the unknown microbes in space.
The experiment on the space station was led by Whitson with guidance from the U.S. space agency’s Sarah Wallace, who is a microbiologist.
"Right away, we saw one microorganism pop up, and then a second one, and they were things that we find all the time on the space station," said Wallace. "The validation of these results would be when we got the sample back to test on Earth."
Further Observations Made During Ground-Based Study
Once the samples and Whitson reached back Earth during September 2017, the next stages of the Genes in Space-3 mission started. Researchers carried out a sequencing of the organisms again, this time, on Earth. It was found that the space sequencing experiment was correct and successful in its identification.
One of the three colonies cultivated and then sequenced on the ISS was Staphylococcus capitis, and the remaining two were Staphylococcus hominis. Both the identified microbes, which are commonly related to the human microbiome, are benign and commonly found in areas occupied by humans. They have also been identified in previous samples, which were sent back from the space station and are not pathogens.
Previously, crew members have used a device known as miniPCR thermal cycler to amplify DNA for observation on the ISS and subsequently sequenced a sample of DNA with the help of the MinION device. It is the first time that both the devices were put together to facilitate important applications of molecular biology.