Earlier this year, scientists in China made an intriguing discovery: a strain of bacteria found aboard the Tiangong space station in 2023 appeared to be a variety never previously identified on Earth.
Following its discovery by members of the Shenzhou-15 mission, the crew swabbed the space station with sterilization wipes, froze the samples they collected, and sent them back to Earth for review.
After its return to Earth, analysis showed the bacteria were closely related to Niallia circulans, a rod-shaped, spore-forming bacterium commonly found in soil, sewage, and food. It is known to cause sepsis in immunocompromised individuals. In other words, the unique sample was indeed a strain of earth-dwelling bacteria, although it showed signs of adaptation to the space station’s unique environment.
The Mayo Clinic describes sepsis as a serious condition in which the body responds improperly to an infection. The infection-fighting processes turn on in the body, causing the organs to work poorly. Sepsis may progress to septic shock, a dramatic drop in blood pressure that can damage the lungs, kidneys, liver, and other organs. When the damage is severe, it can lead to death.
New Adaptations to the Space Environment
The bacteria displayed several adaptations to endure the harsh environment of space, including the presence of genes that help manage oxidative stress, repair radiation-induced damage, and form biofilms by breaking down gelatin to extract carbon and nitrogen.
In a study published this year detailing their findings, the research team noted, “Understanding the characteristics of microbes during long-term space missions is essential for safeguarding the health of astronauts and maintaining the functionality of spacecraft.”
The researchers added that they believe identifying the new bacteria could benefit future space missions for many years and in various ways. Whether the new strain poses a direct risk to humans remains uncertain. However, researchers aim to better understand how it and other microbes adapt to space environments to develop effective strategies to protect astronauts from potential dangers posed by space-adapted bacteria.
Microorganisms in Space
In April, China launched three astronauts (or taikonauts) into space to head to the Chinese Tiangong space station to replace the existing crew onboard. China’s Tiangong, or “Heavenly Palace,” space station has made China a key competing player in the space race. The Chinese-built spacecraft was designed after Congress passed a law prohibiting NASA from collaborating with China aboard the ISS due to U.S. national security concerns.
Understanding microbial life aboard spacecraft becomes increasingly vital as humanity sets its sights on more space missions. The discovery of new bacterial strains like Niallia tiangongensis and the persistent challenges posed by resilient biofilms highlight the complex relationship between microbes and the challenging conditions of space.
Continued research into how these microorganisms adapt, survive, and potentially impact astronaut health and spacecraft integrity is critical to understanding and preparing for future space missions.
By advancing the world’s space exploration knowledge and developing progressive and innovative strategies to monitor and control microbial growth, researchers can better protect astronauts and prepare for commercial travel into deep-space exploration for years to come.
These findings were published in the International Journal of Systematic and Evolutionary Microbiology.
Chrissy Newton is a PR professional and founder of VOCAB Communications. She currently appears on The Discovery Channel and Max and hosts the Rebelliously Curious podcast, which can be found on YouTube and on all audio podcast streaming platforms. Follow her on X: @ChrissyNewton, Instagram: @BeingChrissyNewton, and chrissynewton.com.
