Scientists are reporting "laboratory resurrections" of several 2-3-billion-year-old proteins that are ancient ancestors of the enzymes that enable today's antibiotic-resistant bacteria to shrug off huge doses of penicillins, cephalosporins and other modern drugs. The achievement, reported in the Journal of the American Chemical Society, opens the door to a scientific "replay" of the evolution of antibiotic resistance with an eye to finding new ways to cope with the problem. Jose M. Sanchez-Ruiz, Eric A. Gaucher, Valeria A. Risso and colleagues explain that antibiotic resistance existed long before Alexander Fleming discovered the first antibiotic in 1928. Genes that contain instructions for...