Melvin Calvin

---

AMERICAN CHEMIST
1911–1997

Melvin Calvin was born to immigrant parents on April 8, 1911, in St. Paul, Minnesota. Calvin's family subsequently moved to Detroit, where young Calvin attended high school. With the help of a scholarship he attended the Michigan College of Mining and Technology (now Michigan Technological University) during the years 1927 to 1931 as its first chemistry major. He received a bachelor of science degree in 1931. Because offerings in chemistry were few, he took courses in disciplines such as mineralogy, geology, paleontology, and civil engineering, which helped him in his later interdisciplinary research.

Calvin continued his studies at the University of Minnesota, where he investigated the electron affinities of halogen atoms. He received a Ph.D. degree in 1935. As a Rockefeller Foundation fellow at the University of Manchester in England (1935–1937), Calvin worked with Michael Polanyi, who introduced him to the interdisciplinary approach, on coordination catalysis , the activation of molecular hydrogen, and metalloporphyrins. In 1937 he joined the faculty of the University of California, Berkeley, as an instructor, and remained there for the balance of his career.

During the early 1940s Calvin worked on molecular genetics. He proposed that hydrogen bonding was involved in the stacking of nucleic acid bases within chromosomes. During World War II he produced an oxygen-generating apparatus that used cobalt complexes that bond reversibly with oxygen, for use in submarines and on destroyers. As a member of the Manhattan Project , he used chelation and solvent extraction to purify and isolate plutonium from the fission products of irradiated uranium.

In 1942 Calvin married Genevieve Jemtegaard. After their first child Elin's death, related to Rh factor incompatibility, Calvin and his wife were part of an interdisciplinary project that investigated the etiology of the disease. They helped to determine the composition and structure of the Rh factor, named elinin for their daughter.

In 1946 Calvin began to investigate photosynthesis . He added carbon dioxide containing the radioactive isotope carbon-14 (as a tracer) to a suspension of the single-celled green alga Chlorella pyrenoidosa. By stopping the plant's growth at various stages and then isolating and identifying the radioactive compounds (present in minute amounts), he determined most of the reactions that comprise the intermediate steps of photosynthesis, by which carbon dioxide is converted into carbohydrates. He found that the so-called dark reactions of photosynthesis (now known as the Calvin cycle) is driven by compounds produced in the "light" reactions, which occur as a result of the absorption of light by chlorophyll (producing oxygen). This first use of carbon-14 to elucidate a chemical pathway earned Calvin the Nobel Prize in chemistry in 1961. Using isotopic tracer techniques he also traced the path of oxygen in photosynthesis.

When his bioorganic research group outgrew its quarters (at Berkeley), Calvin himself designed the Laboratory of Chemical Biodynamics. His design of a circular building included spacious laboratories, many windows, and few walls. He directed the laboratory until his retirement (1980), at which time it was renamed the Melvin Calvin Laboratory. He died in Berkeley, California, on January 8, 1997, after several years of declining health.

SEE ALSO Manhattan Project ; Nucleic Acids ; Photosynthesis .

George B. Kauffman

Bibliography

Calvin, Melvin (1964). "The Path of Carbon in Photosynthesis." In Nobel Lectures, Including Presentation Speeches and Laureates' Biographies 1942–1962. New York: Elsevier.

Calvin, Melvin (1992). Following the Trail of Light: A Scientific Odyssey. Washington, DC: American Chemical Society.

Kauffman, George B., and Mayo, Isaac (1994). "Melvin Calvin's Trail of Light." The World & I 9(5):206–213.

Kauffman, George B., and Mayo, Isaac (1996). "Multidisciplinary Scientist—Melvin Calvin: His Life and Work." Journal of Chemical Education 73(5):412–416.