Engineered peptide kills highly resistant bugs

An engineered peptide could kill an entire category of highly resistant bugs that are behind potentially lethal infections such as pneumonia and sepsis. The synthetic drugs acts by shredding and dissolving their double-layered membranes, believed to shield these gram negative bugs from antibiotics, which include E. coli and those that cause gonorrhea, typhoid fever, cholera, syphilis, plague, and Lyme disease. "The antibiotic pipeline against multidrug-resistant Gram-negative problem pathogens is a major unmet need in contemporary medicine; as such, our new antimicrobial agent holds immediate promise," said study co-author Wadih Arap, professor at the University of Texas MD Anderson's Cancer Centre, the journal Proceedings of the National Academy of Science reports. Arap, Renata Pasqualini, also study co-author and professor at Texas Cancer Centre, and colleagues have previously constructed peptide combinations that are in development against cancer and white fat cells, according to a Texas statement. "The prototype introduced here as an antibiotic candidate has a unique mechanism of action and translational applications readily identified," Pasqualini said. The spiral peptide called KLAKLAKKLAKLAK acts against bacteria by puncturing their lipid bilayer membranes and has only low toxicity toward mammalian cells.