The battle against antibiotic resistant superbugs is one of the biggest challenges medical researchers are facing in the 21st century. But not all pathogenic bacteria needs to evolve a variant to avoid destruction from antibiotics. A new study has revealed that some bacteria can effectively enter a state of hibernation, waiting for the effects to antibiotics to pass, resulting in persistent and chronic infections.

One of the ways antibiotics work is by preventing bacterial growth. Different antibiotics utilize different techniques to achieve this, but in general the bacteria must replicate in order to be killed. One strategy pathogenic bacteria use to avoid antibiotics is to slow growth temporarily when antibiotics are present.

"We studied E. coli bacteria from urinary tract infections that had been treated with antibiotics and were supposedly under control," explains Kenn Gerdes, one of the researchers on the new study. "In time, the bacteria re-awoke and began to spread once again."

This process tends to explain why some people suffer from persistent recurring infections. Courses of antibiotics can stifle the growth of certain bacterial pathogens but some bacteria can enter this hibernation phase and avoid destruction.

"A bacterium in hibernation is not resistant. It is temporarily tolerant because it stops growing, which allows it to survive the effects of an antibiotic," says Gerdes.

The new research set out to discover how bacteria triggers this dormant phase. Using a relatively new method called phosphoproteomics, the researchers revealed that E. coli bacteria can produce a specific enzyme that inhibits its growth leading to physiologically dormant state.

It's unclear at this stage why, in a given bacterial population, some bacteria can trigger this enzyme and go dormant while others do not, but the study suggests the discovery offers exciting research pathways toward new drugs that can attack these hibernating bacterial cells.

"The enzyme triggers a 'survival program' that almost all disease-causing bacteria deploy to survive in the wild and resist antibiotics in the body," says Gerdes. "Developing an antibiotic that targets this general programme would be a major advance."

The research was published in the journal Science Signaling.