Antibiotic treatments are losing effectiveness against a range of common bacterial pathogens, including E. coli, K. pneumoniae, Salmonella and Acinetobacter, according to a warning issued by the World Health Organization last October. For the microbe that gives rise to tuberculosis, a team of researchers from Penn State and The University of Minnesota Medical School found that a potential solution may be chemically changing the structure of a naturally occurring peptide—a building block of proteins—to make it a more stable and effective antimicrobial agent, while reducing potential toxicity to human cells.