According to the Centers for Disease Control and the World Health Organization, antibiotic-resistant bacteria are flourishing worldwide amid overuse of antibiotic wonder drugs. Yet, Dr. Daniel Nelson and his team at IBBR are developing ways to fight bacterial pathogens without antibiotics by exploiting a process that occurs billions of times per second globally. Cueing the old proverb, “the enemy of my enemy is my friend”, bacteriolytic enzymes produced by viruses that naturally infect bacteria can be harnessed for their ability to lyse bacteria on contact. These enzymes, known as enzybiotics (for ENZYme antiBIOTICS), break chemical ties in the bacterial cell wall. The high internal pressure of the bacterial cell causes it to explode and die once the rigid structure of the cell wall is compromised by the enzybiotic. Not only do enzybiotics act on contact, but they are highly species specific, meaning they can target pathogenic organisms yet are harmless to commensal organisms (i.e. good bacteria), a benefit not offered by even the most advanced antibiotic. On the human side, enzybiotics have been developed that target methicillin-resistant Staphylococcus aureus (i.e. MRSA), Clostridium difficile, Streptococcus pyogenes, and Bacillus anthracis (anthrax). On the animal side, enzybiotics have been developed for Streptococcus equi (equine strangles disease), Streptococcus suis (meningitis and other infections in pigs), Streptococcus uberis (bovine mastitis), and Staphylococcus aureus (bovine mastitis). Some of the first generation enzybiotics have already begun clinical trials. The Nelson laboratory is studying the host-pathogen relationship between bacteria and their viruses to bioengineer the viral enzymes with enhanced properties (i.e. greater activity or host range) in order to develop the next generation of enzybiotics.