BME Researchers Discover How Superbugs Become Resistant to Antibiotics
Posted Feb 14 2010 7:04am
Many people with bacterial infections stop taking antibiotics when their symptoms improvethereby allowing the hardy bacteria that survive to multiply and potentially mount a more powerful defense against future applications of the same drug. But a new study led by Professor James Collins (BME) indicates that sub-lethal doses of an antibiotic can trigger anothermore alarming outcomein which the targeted bacteria become cross-resistant to multiple antibiotics.
CollinsBME graduate student Michael Kohanski and post-doc Mark DePristo described their research in the Feb. 12 edition of Molecular Cellfindings that could spark considerable changes in how antibiotics are used across the globe as the public health community strives to combat the proliferation of multidrug-resistant strains of bacteriathe so-called “superbugs.”
Two years agothe researchers had proven that when applied in lethal dosesantibiotics stimulate the production of reactive oxygen species (ROS) moleculesor free radicals that damage DNAprotein and lipids in bacterial cellscontributing to their demise. In the Molecular Cell studythey demonstrated that the free radicals produced in targeted bacteria by a sub-lethal dose of an antibiotic live on to accelerate the formation of mutations that protect against a variety of antibiotics other than the administered drug.