James Batcheller Sumner

1887-1955

American Biochemist

On his way to winning the 1946 Nobel Prize for Chemistry, James B. Sumner overcame not only a physical handicap, but prevailing scientific opinion. At that time the received wisdom held that, first of all, it was impossible to isolate an enzyme, and furthermore, that enzymes were not proteins. Sumner proved both assertions wrong.

Born in Canton, Massachusetts, on November 19, 1887, Sumner was the son of Charles and Elizabeth Kelly Sumner. They were a wealthy family whose New England lineage went back all the way to 1636, and they lived on a large estate. There the young Sumner enjoyed hunting and shooting, a hobby that resulted in tragedy when he lost his left forearm and elbow in a shooting accident. This was a particularly great misfortune due to the fact that he was left-handed, but he learned to work with his right.

Sumner originally enrolled at Harvard University to study electrical engineering, but soon discovered that he preferred chemistry, and in 1910 graduated with a degree in that discipline. After working briefly in a family business, followed by a stint as a chemistry teacher, he went on to his doctoral studies at Harvard in 1912. In 1914 he received his Ph.D. with a thesis on "The Importance of the Liver in Urea Formation from Amino Acids," published in the Journal of Biological Chemistry.

In 1915 Sumner married Bertha Louise Ricketts, with whom he would have five children. By then he had taken a position as assistant professor in the department of biochemistry at the Ithaca Division of Cornell University Medical College. Sumner would spend his entire career at Cornell.

Due to a heavy teaching load, Sumner lacked the time, as well as the research funds, to conduct lengthy or cost-intensive studies. Therefore, he reasoned that enzyme research would be a good undertaking, since he could fit the project into his time and money constraints. Furthermore, popular doubts about this enterprise meant that the rewards of success in such a long-shot effort would be great. Therefore, in 1917 he began his efforts to isolate an enzyme.

It took Sumner nine years to crystallize urease, which catalyzed the breakdown of urea into ammonia and carbon dioxide. Because it contained relatively large quantities of the enzyme, he chose to work with the jack bean. In 1926 he published his findings in the Journal of Biological Chemistry, reporting that he had isolated what he believed to be urease—and that he had proven it to be a protein.

Sumner's report earned him plenty of detractors, most notably German chemist Richard Willstätter (1872-1942), winner of the 1915 Nobel Prize for his work on chlorophyll. Willstätter, who himself had tried unsuccessfully to isolate an enzyme, contended that Sumner had merely crystallized the carrier of the enzyme rather than the enzyme itself. Yet, when John Howard Northrop (1891-1987) of the Rockefeller Institute crystallized pepsin in 1930, this bolstered Sumner's argument.

In 1946 Sumner and Northrop—along with Wendell Meredith Stanley (1904-1971), whose work concerned virus proteins—jointly received the Nobel Prize for Chemistry. In the meantime, Sumner remained busy with laboratory work, researching other enzymes and publishing his results in more than 125 papers and books. He also had a number of personal changes during the 1930s and 1940s. In 1930 he and Bertha divorced, and Sumner remarried to a Swedish woman named Agnes Lundquist the following year. Sumner and Agnes were later divorced, and in 1943 he married Mary Morrison Beyer, with whom had two sons, one of whom died in childhood.

In addition to his Nobel, Sumner received numerous honors from Sweden, Poland, and the United States. He belonged to a number of associations, among them the National Academy of Sciences and the American Association for the Advancement of Sciences. Sumner was preparing to retire from Cornell and to organize an enzyme research program at a medical school in Brazil when he was diagnosed with cancer. He died on August 12, 1955, at a hospital in Buffalo, New York.

JUDSON KNIGHT