The researchers discovered that several unrelated viruses deactivate the key bacterial protein MurJ, which is essential for the construction of the bacterial cell wall. These viral proteins lock MurJ into one position, stopping the building of the cell wall and leading to the death of the bacteria. High-resolution imaging shows how viral proteins act as a wedge that blocks MurJ function. MurJ transports the building blocks of the cell wall, called Lipid II, across the cell membrane. Antibiotic-resistant bacteria are becoming increasingly difficult to treat, forcing the search for new targets for treatment. This discovery could change the fight against superbugs.