His research has been at the boundary of chemistry and biochemistry. He has been particularly interested in the rate and specificity of enzyme catalysis and the evolution of protein function. He has published more than 250 research papers.
Knowles was born in England, where he was educated at Magdalen College School, Oxford. After serving as a pilot officer in the Royal Air Force, he graduated from Balliol College, Oxford, receiving his B.A. in 1959 and his D. Phil. in 1961. Before joining the Harvard faculty, he was fellow and tutor of Wadham College, Oxford. He also held a postdoctoral fellowship at the California Institute of Technology and was a visiting professor at both Harvard and Yale.
Knowles was elected a fellow of the Royal Society in 1977, and to membership in the American Academy of Arts and Sciences in 1982. In 1984, he was elected to an honorary fellowship of Balliol College, and in 1990, to an honorary fellowship of Wadham College, Oxford. He became a foreign associate of the National Academy of Sciences and a member of the American Philosophical Society in 1988.
Knowles has received many awards, including the Charmian Medal of the Royal Society of Chemistry, the Bader Award and an Arthur Cope Scholar Award from the American Chemical Society, the Davy Medal from the Royal Society, and the Robert A. Welch Award. He was appointed Commander of the British Empire in the Queen’s Birthday Honours of 1993.
Knowles will become one of the nine Trustees of the Howard Hughes Medical Institute, which is among the largest philanthropies in the world. The Institute’s scientists conduct basic biomedical research in hundreds of laboratories located on the campuses of the universities, academic medical centers, and other research institutions in the United States with which the Institute collaborates. HHMI also has a large grants program through which it supports science education at every level in the United States, as well as the work of individual scientists in selected foreign countries.