They Came from Space… Superbugs!

Unlike the space tourists who have paid tens of millions of dollars to throw off the surly bonds of gravity, I’ve never had a desire to fly to the moon or beyond. Sure, space is fascinating, but hurtling through it in a cramped capsule just doesn’t sound appealing (overseas flights are bad enough). Now, a new study suggests that along with tipsy astronauts, cramped quarters—and the risk of explosion—there’s one more thing for space travelers to worry about: superbugs. A research team led by astrobiologist Cheryl Nickerson at Arizona State University found that getting a lift to and through space on the Space Shuttle Atlantis increased the virulence of Salmonella typhimurium, the same bacteria that infects human digestive tracts, to very unpleasant effect. Space travel altered the expression of more than 150 S. typhimurium genes, and the resulting strain kills mice more quickly—and at lower doses—than earthbound S. typhimurium (animals that you might call "ground controls"). The authors believe a protein called Hfq may regulate the bug’s response to the effects of microgravity and other space conditions. Researchers suspected something strange would happen to bacteria in space, given that they act a bit wonky when grown in NASA-designed space-simulating labs. But it wasn’t until the intrepid bacteria returned home that scientists could measure the real effects of space. As we aim for more distant targets such as Mars, spaceflights will inevitably get longer, and infectious disease is a real concern; during the notorious Apollo 13 flight, one astronaut suffered from a urinary tract infection. By noodling out the cellular mechanisms of dangerous bacteria with experiments like these, scientists may find new ways to keep nasty critters from infecting us—especially those of us with the guts and gumption to ride rockets into space.