Masayori Inouye, a distinguished professor at the Rutgers Robert Wood Johnson Medical School, has cut a wide swath in biochemistry and molecular biology. His wide-ranging accomplishments include the determination of genetic codons in a protein and thus, for the first time, a partial DNA sequence of a gene, elucidation of the mechanism of biogenesis and assembly of membrane proteins, and creation of a protein-synthesizing bioreactor, among others. Many of his findings hold promise for application in biotechnology and clinical medicine. Inouye, who was elected to the National Academy of Sciences in 2019, is now trying to determine how genetic codons first evolved. Inouye’s Inaugural Article presents his hypothesis that primordial proteins consisted of seven amino acids, which he is using to synthesize an enzyme that may have been fundamental to the origin of life.