Klebsiella pneumoniae is the leading cause of healthcare-associated infections worldwide. These infections are typically treated using a class of antibiotics called carbapenems, which travel into the bacterial cell through membrane pores called porins. However, resistance is emerging, which is a significant clinical threat. Professor Gad Frankel and team analysed large genome collections to identify a variety of mutations in the ompK36 gene that drive resistance. They also measured the frequency of such mutations. Further analyses revealed the resulting effects on the associated porin proteins. For example, some mutations narrow the diameter of the pore to restrict the diffusion of the antibiotics into the cell while others disrupt its translation. Their work highlights the need for therapies that circumvent the reliance on diffusion by porins. Read the publications in PLoS Pathogens (2022) and PNAS (2022).