'Space flight alters cellular and physiological responses in astronauts including the immune response. However, relatively little was known about microbial changes to infectious disease risk in response to space flight,' said Nickerson, who led a project aboard NASA's space shuttle mission STS-115.
The September 2006 mission involved a large, international collaboration between NASA, ASU and 12 other research institutions.
Cheryl Nickerson and lead author James Wilson, both professors in from the Biodesign Institute at Arizona State University's School of Life Sciences, performed study, the first of its kind, to investigate the effect of space flight on the genetic responses and disease-causing potential, or virulence, of Salmonella typhimurium, the main bacterial culprit of food poisoning.
They sent specially contained tubes of Salmonella in an experimental payload aboard the Space Shuttle Atlantis. The tubes of bacteria were placed in triple containment for safety and posed no threat to the health and safety of the crew during or after the mission.
Upon their return, they were compared to bacteria that remained on earth. The findings published in the journal Proceedings of the National Academy of Sciences revealed a key role for a master regulator, called Hfq, in triggering the genetic changes that showed an increase in the virulence of Salmonella as a result of spaceflight.
The space-travelling Salmonella had changed expression of 167 genes.
Animal virulence studies further showed that the bacteria that were flown in space were almost three times as likely to cause disease when compared with control bacteria grown on the ground.
The researchers say the results of these studies hold potential to greatly advance infectious disease research in space and here on Earth, and might lead to the development of new therapeutics to treat and prevent infectious disease.