For years, sci­en­tists and sci­ence writers have been sounding loud alarmsabout drug-​​resistant bac­teria that can shrug off our most potent antibi­otics. They are hard to kill, and so kill us with greater ease. These super­bugs are unde­ni­ably wor­rying but they’re only part of the problem—it is entirely pos­sible for bac­teria to defy antibi­otics without actu­ally resisting them.

All of our antibi­otics are designed to kill fast-​​growing microbes. Bac­teria can weather these assaults by entering a dor­mant state, and waiting until the drugs have worn off. These sleeper cells are called per­sis­ters. They’re the reason why bac­teria some­times cause long-​​lasting infec­tions that repeat­edly bounce back despite our best attempts to treat them. Each wave of drugs wipes out most of the microbes, but a small group of per­sis­ters can sur­vive to re-​​start a new wave of infection.

Per­sis­ters are not drug–resis­tant; if you whacked them with antibi­otics while they were growing, they’d die. But give the same drugs to a patient, and not much hap­pens. The bac­teria sur­vive because of their dor­mant nature, because of how they behave rather than what they are.

We’ve known about per­sis­ters since the 1940s, but they are hard to study and to kill. Many sci­en­tists are tack­ling the issue of drug resis­tance but per­sis­tence has, iron­i­cally enough, lain largely dormant.

But Kim Lewis from North­eastern Uni­ver­sity has now found an exciting way of killing per­sis­ters, with an antibi­otic called ADEP4 that forces these cells to eat them­selves in their sleep. He hasn’t tested it in humans yet, but it can com­pletely clear severe and long-​​lasting infec­tions in mice. It even kills per­sis­ters that are also resis­tant to tra­di­tional antibi­otics, such as MRSA. It’s a very impor­tant mile­stone,” says Lewis.

Read the article at National Geographic →