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Moses Kunitz, 1924

Courtesy of the Marine Biological Laboratory Archives

Moses Kunitz (1887–1978) was a Russian-American biochemist who is best known for a series of experiments in the purification and crystallization of proteins, contributing to the determination that enzymes are proteins. He spent most of his career at Rockefeller University.

Kunitz's position at Rockefeller was originally secured by Jacques Loeb. After Loeb died in 1924, John H. Northrop succeeded him and retained Kunitz's position; the two would collaborate extensively on experiments involving protein crystallization for much of their remaining careers. Both Northrop and Kunitz moved to Rockefeller's Princeton, New Jersey campus in 1926; Kunitz returned to New York City in 1952. He then assumed professor emeritus status but continued to work regularly in the laboratory until eventually retiring in 1970.

Kunitz was awarded the Carl Neuberg Medal in 1957 in recognition of his long research career and noted technical skill in the laboratory, which was critical to his long series of successes in protein crystallization. He was elected to the National Academy of Sciences in 1967. In addition to his work on the crystallization of proteases, Kunitz also performed careful work in enzymology, characterizing the kinetics and thermodynamics of protease reactions. He worked on other proteins as well, in particular ribonucleases, which were popular model systems for their small size and ease of crystallization. During World War II he worked on government-assigned crystallization projects and was noted for the facility with which he crystallized hexokinase. Kunitz was widely recognized specifically for his craftsmanship and technical skill in the laboratory.

Years at The Rockefeller University: 1913-1953; emeritus 1953-1978


protein crystallization, biochemistry


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