Mechanisms of ribosome inhibition by context-dependent antibiotics – RibioTiX

The bacterial ribosome is a major antibiotic target. Although drugs that target the ribosome have largely been regarded as general inhibitors of translation that prevent the synthesis of all proteins with the same efficiency, a more nuanced view of antibiotic action has emerged in recent years. Indeed, ribosomes interact with numerous ligands during translation and it is becoming increasingly clear that certain ribosome-targeting antibiotics affect protein synthesis in a context-dependent manner. Here, we propose to systematically assess the ability of most major classes of ribosome-targeting antibiotics to impact translation in a context-dependent manner, and to revise the mechanisms of action of these antibiotics accordingly. To do so, we will use inverse toeprinting to measure ribosomal stalling landscapes in the presence of more than two-dozen antibiotics, as well as biochemistry and high-resolution cryo-EM to determine the context-dependent mechanisms of action of 3-5 antibiotics. In doing so, we will provide the molecular details necessary for the development of improved antibiotics using a structure-based approach.