Evidence of the bacterial transfer during space missions

Most modern organisms require specific conditions to survive: liquid water, oxygen, moderate temperatures, stable aboveground air pressure, and low-level radiation exposure. However, not all terrestrial organisms live harmoniously under such moderate conditions; in fact, there are extremophiles living in generally life-threatening environments, and several “ordinary” microbes are capable of readily adapting to extreme conditions.

An extract from Biotechnqiues:

According to a meta-analysis by the International Space Station’s (ISS’s) microbial research teams, humans bring large microbiomes on board even after going through pathogen-removal quarantine for 10 days before entering the spacecraft. Lingering microbes sparked several ideas in astrobiologists wanting to see how microorganisms change in the ISS and space shuttle’s closed-system microgravity environments.

Between 2006 and 2008, researchers sent several Salmonella typhimurium samples into low-Earth orbit on the space shuttles Atlantis and Endeavour. Once returned to Earth, the S. typhimurium was injected into mice and found to be more virulent than usual.

These findings left scientists wondering if the ability of microbes to adapt to new environments poses greater contamination threats than originally thought.

For further details see:

Osman S, Peeters Z, La Duc MT, Mancinelli R, Ehrenfreund P, Venkateswaran K. Effect of Shadowing on Survival of Bacteria under Conditions Simulating the Martian Atmosphere and UV Radiation. 2008. Journal of Appl. And Env. Microbio. doi: 10.1128/AEM.01973-07

Posted by Dr. Tim Sandle