1920-

French biochemist who won the 1965 Nobel Prize for contributing to discoveries about the genetic regulation of enzymes. With Elie Wollman he proved that bacteria are able to exchange genetic material during a sexual reproductive process called conjugation. This discovery allowed the mapping of the bacterial chromosome. Work on bacteriophage viruses led to the development of the operon theory of genetic control, which predicted the existence of messenger RNA and the role of repressors in gene expression.