Visualizing antibiotic action in a pathogenic bacterium at atomic to cellular scale

The mechanisms of antibiotic action can be highly context specific. Using in-cell cryo-electron tomography (cryo-ET) of Mycoplasma pneumoniae — a causative agent of respiratory disease — we visualized the context-dependent action of the ribosome-targeting antibiotic chloramphenicol simultaneously at atomic, molecular and cellular levels. This work highlights how in-cell structural biology can expand our understanding of antibiotic mechanisms of action.