Good news from New Scientist – the so-called superbug has met its germ-killing kryptonite:
These bacteria are resistant to the most widely used class of antibiotics, called beta-lactams, which include penicillin, methicillin and carbapenems.
These drugs work by targeting essential components of a bacterium’s cell wall called peptidoglycans. But MRSA protects itself by using a type of molecule that can soak up the drug and stop it from working.
Now Christopher Tan and colleagues at Merck Research Laboratories in New Jersey have found a way to break this resistance. They have identified two compounds that make beta-lactam antibiotics powerful against MRSA again.
Called tarocin A and tarocin B, these compounds target a different part of a bacterium’s cell wall, called teichoic acid. Neither of these drugs kill bacteria on their own, but when either one is combined with an antibiotic, the combination can kill MRSA in both clinical samples and in infected mice.
“It’s like a two-prong attack,” says David Brown, of the charity Antibiotic Research UK. “They’re weakening the wall by a second mechanism, which makes it easier for the beta-lactams to have their effect as well.”