wired.com: By Brandon Keim

Infectious diseases may have an unexpected weakness: their own propensity for laziness. Researchers genetically engineered “cheating” versions of a common, inflammation-causing microbe. When injected into already-infected mice, the bugs benefited from the chemical labors of other microbes without working themselves. Able to devote their energies to reproduction, the lazy bugs divided faster than their brethren, and infections turned rapidly less virulent.

“The wild bacteria expend all this energy to make these signaling compounds and virulence factors. That slows down their growth,” said Kendra Rumbaugh, a microbiologist at Texas Technical University and lead author of the study, published Thursday in Current Biology. “The cheaters save up like crazy, divide like crazy, and take over the population.” [ read more ]