Demain advanced the field of fermentation biology, and made major contributions to the study of antibiotics such as penicillin, cephalosporin, and beta-lactam. He discovered the enzyme deacetoxycephalosporin C synthase, which transforms penicillins into cephalosporins. Later in his career, he examined Clostridium tetani and Clostridium difficile bacteria in hopes of devising tetanus and antibiotic-associated diarrhea vaccines. He ultimately authored more than 500 publications and 21 patents.

Photo credit: Steven Brener