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Salmonella bacteria sent into our space responded to the altered gravity by becoming more virulent, with changed expression of 167 different genes, according to a study published in the Proceedings of the National Academy of Sciences.

"These bugs can sense where they are by changes in their environment," said Cheryl Nickerson, from the Center for Infectious Diseases and Vaccinology at Arizona State University (ASU). "The minute they sense a different environment, they change their genetic machinery so they can survive.“

Researchers placed strains of Salmonella typhimurium, a common food-poisoning agent, into two separate containment canisters. One of the canisters was sent into outer space for 12 days,while the other remained in the Orbital Environmental Simulator at Kennedy Space Center. The environmental simulator remained in constant communication with the space shuttle, immediately replicating in real-time whatever temperature and humidity conditions were being experienced in the vessel. This allowed the two groups of bacteria to be exposed to identical conditions, except for the fact that one group were under microgravity conditions in outer space.

The findings may be significant not only for those who travel in space, but also in terms of what microbes astronauts are bringing back.

"Wherever humans go, microbes go; you can't sterilize humans," Nickerson says. "Wherever we go, under the oceans or orbiting the Earth, the microbes go with us, and it's important that we understand how they're going to change.“

Nickerson also says that since S. typhimurium exists in a natural microgravity in the human gut, understanding how environmental conditions regulate the organism's virulence may help lead to better treatments.

In addition to researchers from ASU, scientists also participated in the study from the Johnson and Kennedy Space Centers, Kimmel Cancer Center, NASA Ames Research Center, Oklahoma City University, Tulane University, University of Arizona, University of Chicago, University of Colorado at Boulder and Denver, Southeast Louisiana Veterans Health Care System, and the Max Planck Institute for Infection Biology in Berlin.

(Source: naturalnews.com, 2008)