Part of a riboswitchWIKIMEDIA, FDARDELResearchers at the pharmaceutical company Merck have identified a new bacteria-killing compound with an unusual target—an RNA regulatory structure called a riboswitch. The team used its drug, described in Nature today (September 30), to successfully reduce an experimental bacterial infection in mice, suggesting that the molecule could lead to the creation of a new antibiotic. Moreover, the results indicate that riboswitches—and other RNA elements—might be hitherto unappreciated targets for antibiotics and other drugs.
“Finding an antibiotic with a new target . . . has always been one of the holy grails of antibiotics discovery,” said RNA biochemist Thomas Hermann of the University of California, San Diego, who was not involved in the work. “It looks like that’s what the Merck group has now accomplished.”
The team’s research began with the idea of finding a compound that blocks the bacterial riboflavin synthesis pathway. Riboflavin is an essential nutrient for humans and bacteria alike, but while humans must consume it as part of their diet, bacteria can either scavenge riboflavin from the environment or, if supplies are lacking, make their own. “We targeted the riboflavin pathway because it is specific to bacteria so you have a built in safety margin,” ...