'Superbugs' Could Benefit Humans

Zero Gravity and Radiation Produce Powerful Microbes

Truth or fiction?

¿ A high school student gains superpowers after being bitten by a radioactive spider.

¿ An electron beam meant to clean up a bioterrorism site transforms a mild-mannered microbe into a life form able to withstand radiation doses hundreds of times stronger than would kill a person.

¿ Altered by the absence of gravity, an everyday bacterium aboard a spacecraft mutates into a highly lethal bug that poses a surprise threat to astronauts.

Okay, Spider-Man is still fiction. But a pair of independent studies has brought the other two scenarios to life.

The twin tales of menacing mutants are stark reminders of the microbial kingdom's immense versatility -- and of the inadvertent biological transformations that can be wrought by human activities.

But they also point to potential new therapies for cancer and infectious diseases that otherwise might never have been identified.

"When we push the frontier and push biological systems to their limits to see what they can do, that's often when we get the breakthrough insights," said Cheryl Nickerson, a microbiologist at Arizona State University in Tempe, whose experiment led to the creation of lethal bacteria on a recent space shuttle mission -- in fully sealed containers, she emphasized.

That experiment, flown aboard the shuttle Atlantis last fall, was the first to test in true weightlessness a curious observation: In conditions mimicking microgravity on Earth, bacteria undergo changes that make them more deadly.