Chemists from Innsbruck and New York managed to monitor single-molecule switching in action. In an article in “Nature Chemical Biology” they report their findings: The secret of bacterial riboswitches lies in their dynamics. These findings are also relevant in antibiotics research.
In various ways, bacteria are one step ahead to us humans. For example, they dispose of “intelligent” RNA molecules, so-called riboswitches, which help to regulate many of their essential metabolism pathways. The riboswitches, only discovered a few years ago, are sensors in RNA molecules. A riboswitch acts similarly to a motion sensor that switches on or off the light when people are nearby: the riboswitch switches genes off or on when certain metabolism products are present in a cell. There is no similar mechanism of gene regulation in humans, therefore this represents an ideal target for new antibiotics. However, how the sensoring and switching process is transduced has remained widely unexplained since the discovery of riboswitches. Now, an international team under the leadership of chemists from Innsbruck succeeded in monitoring the S-adenosylmethionine (SAM) II-riboswitch in action. SAM is a cofactor which is involved in many metabolism processes by transferring methyl groups to other molecules.