Ninety years after the discovery of the first antibiotic, penicillin, researchers have found an entirely new tactic in the fight against bacteria that cause infectious diseases. Instead of hunting for new ways to kill bacteria, researchers have developed a drug, called LED209, that disarms them, preventing them from releasing the toxins that cause illness.
“The sensors in bacteria are waiting for the right signal to initiate the expression of virulent genes,” [said lead researcher] Vanessa Sperandio…. “Using LED209, we blocked those sensing mechanisms and basically tricked the bacteria to not recognize that they were within the host” [Reuters]. The new technique, which has only been demonstrated in mice so far, could be a boon for researchers who are worried about creating more antibiotic-resistant “superbugs.”
Superbugs evolve when a few bacteria mutate into a form that can survive a dose of antibiotics; those few that survive are given a huge boost by this natural selection, and the antibiotic-resistant strain spreads. [B]ecause LED209 doesn’t kill bacteria, the one bug in a billion that’s lucky enough to be resistant to the drug won’t get much of a growth advantage – the key to antibiotic resistance. “You’re not wiping the other ones out,” [Sperandio] says. “You’re having a softer evolutionary pressure against resistance” [New Scientist].
In the study, published in the journal Science [subscription required], researchers showed that mice treated with the new drug didn’t get sick when exposed to bacteria like samonella, and to a potentially lethal bacteria that causes an illness called tularemia, or “rabbit fever.” Four-fifths of the [treated] animals survived tularaemia, whereas just 10% of the untreated mice pulled through [New Scientist].