Francois Jacob studied in bacteria and bacteriophages at the Institut Pasteur in Paris, France, in the second half of the twentieth century. In 1965, Jacob won the Nobel Prize in Physiology or Medicine with Andre M. Lwoff and Jacques L. Monod for their work on the genetic control of enzyme synthesis. Jacob studied how genes control and regulate metabolic enzymes in the bacterium Escherichia coli (E. coli) and in lysogenic bacterial systems. He contributed to theories of transcriptional gene regulation, the operon model, and the distinction between structural and regulatory genes. Jacob also introduced the concept of bricolage (tinkering) in evolutionary biology.