The superbug MRSA (methicillin-resistant Staphylococcus aureus) has provoked fear in doctors and patients alike because it is endowed with genetic characteristics that make it impervious to many antibiotics, and it can be deadly to boot. Less well known, however, is another class of bacteria that also resist antibiotics, but for reasons that have puzzled scientists. These bugs cause stubborn infections in ears and urinary tracts and post-surgical wounds, even though, from their genetic profiles, they should be perfectly good targets for antibiotics.
Researchers are now starting to figure out how these bacteria withstand antibiotic treatment: by exploiting the same traits that have helped them endure environmental stressors. Two new research papers, published Friday in Science, show how bacteria use their ability to withstand prolonged periods without food or exposure to reactive oxygen to also fight off antibiotics. Knowing what these defenses are could lead to new ways of making existing therapies more effective.