Old antibiotics are being revived to fight new threats

An alarming increase in bacterial infections that don’t respond to many medicines has forced physicians to reach for outdated drugs at the back of the cupboard. In doing so, however, they might have stumbled on a wellspring of options for tackling the threat of antimicrobial resistance. The unfashionable antibiotics in question are antimicrobial peptides (AMPs). Microorganisms, insects and mammals alike make thousands of these small proteins, typically no more than 60 amino acids in length. …