Antibiotics share killing mechanism

All three major classes of antibiotics share a single mechanism for killing bacterial cells, reports this week's Cell. Although these drugs initially have different effects on bacterial cells, they all converge on a pathway that kills cells by generating highly reactive free radicals. The results suggest new ways of improving antibiotic effectiveness, the authors say."This is one of those neat, unpredictable findings," said Scott Singleton of the University of North Carolina at Chapel Hill, who was not involved in the study. "It's really not just a linear extension of what we knew before."Drugs that kill bacteria, called bactericidal antibiotics, are grouped into three classes, depending on how the drug damages bacterial cells. One class inhibits DNA replication and repair, another inhibits protein synthesis, and the third prevents cell-wall turnover. "Prior thinking was that cell death arose principally from those interactions and that each [class] acted differently," said senior author...