For the first time, researchers have been able to observe the mode of action of a promising class of alternative antibiotics directly in bacterial cellular membranes. Until now, such studies could only be done in less relevant media, such as organic solvents or micelles. The approach they developed could provide important cues to design drugs for combatting drug-resistant bacteria. Their findings already suggest novel cues to improve the activity of nisin, the most popular antibiotic of this class. The study, led by Dr. Markus Weingarth and Dr. Eefjan Breukink of Utrecht University, was published in Nature Communications on 27 September.