Ponnamperuma, Cyril Andrew

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Ponnamperuma, Cyril Andrew

(b. 16 October 1923 in Galle, Ceylon, now Sri Lanka; d. 20 December 1994 in Washington, D.C.), chemist known for his work on the chemical basis of life and for showing that the basic building blocks of DNA and RNA can be synthesized outside living cells.

Ponnamperuma was one of five children born to Andrew Ponnamperuma and Grace Siriwardene. Both of his parents were educators, and they persuaded him to study philosophy. After attending local schools, Ponnamperuma received a B.A. in philosophy from the University of Madras in 1948. At that point he decided to change his field of study to chemistry. He earned a B.Sc. from the University of London in 1959. While pursuing this degree, he also worked as a research chemist and as a radiochemist. He married Valli Pal on 19 March 1955. They had one daughter. The family immigrated to the United States in 1959, and Ponnamperuma became a U.S. citizen in 1967.

Ponnamperuma entered the University of California at Berkeley in 1959 and received a Ph.D. in chemistry in 1962. While at Berkeley he worked as research associate at the Lawrence Radiation Laboratory, where he collaborated with Melvin Calvin, a Nobel laureate and experimenter in chemical evolution, the chemical paths by which life might have originated. This relationship led to Ponnamperuma’s interest in chemical evolution.

After earning his Ph.D., Ponnamperuma won a one-year fellowship from the National Academy of Sciences to be a research scientist at the National Aeronautics and Space Administration (NASA) Ames Research Center in Mountain View, California. After his fellowship ended, he remained at Ames as a research scientist until 1971. From 1965 to 1971 he served as the chief of the Chemical Evolution Branch. In 1971 he became a professor of chemistry and the director of the Laboratory of Chemical Evolution, an endeavor supported by the National Science Foundation and NASA, at the University of Maryland in College Park. He held these positions until his death.

Although trained as a chemist, Ponnamperuma expressed interest in chemical evolution, exobiology, geochemistry, and space sciences. In his research he explored the chemical paths by which life might have originated and exploited dramatic advances in molecular biology, astrophysics, and micropaleontology. Ponnamperuma constructed a convincing theory about a series of chemical reactions that gave rise to the precursors of life on Earth. To do this he built on the work of Harold Urey and Stanley Miller in the early 1950s. Urey and Miller had experimented with a “primordial soup” concocted of the elements thought to have made up Earth’s early atmosphere, that is, methane, ammonia, hydrogen, and water. By sending electrical sparks through the mixture, they detected the formation of amino acids. Ponnamperuma set up variations of these experiments in the early 1960s. He sent high-energy electrons and then ultraviolet (UV) light through the primordial soup used by Urey and Miller. He succeeded in creating large amounts of adenosine triphosphate (ATP), a substance that fuels cells. In later experiments with the same conditions Ponnamperuma and his group created the nucleotides that make up nucleic acids. In 1984 Ponnamperuma reported the creation of all five chemical bases of living matter in a single experiment of bombarding a primordial soup mixture with electricity.

Ponnamperuma also was active in the growing field of exobiology, the study of extraterrestrial life. He worked with samples of lunar soil and with information sent back from Mars by the unmanned probes Viking, Pioneer, and Voyager in the 1970s.

Ponnamperuma received numerous national and international awards and distinctions, including the 1993 Harold Urey Prize awarded by the Russian Academy of Creative Arts, various honorary degrees, and a distinguished visiting professorship with the Indian Atomic Energy Commission in 1967. He was a fellow of the Royal Institute of Chemistry and the Third World Academy of Scientists and a member of the American Chemical Society, the Astronomy Association, the American Society of Biological Chemists, the American Association for the Advancement of Science, the Geochemical Society, and the Radiation Research Society. Ponnamperuma was also a foreign member of the Indian National Science Academy in 1978, director of the Arthur C. Clarke Center in Sri Lanka from 1984 to 1986, science adviser to the president of Sri Lanka from 1984 until his death, and director of the Institute for Fundamental Studies in Sri Lanka from 1984 to 1991. A member of the International Society for the Study of the Origin of Life, he received its A. I. Oparin Gold Medal in 1980. Ponnamperuma was renowned for his efforts promoting science to underdeveloped countries. At the time of his death he was the director and founder of the North-South Center for Sustainable Development, created by the Third World Foundation. The center’s mission is to facilitate the exchange of scientific information and technology between industrialized and developing countries.

Ponnamperuma’s scholarly work includes editorships of the Journal of Molecular Evolution from 1970 to 1972 and of Origins of Life from 1973 to 1983. He contributed many articles to professional journals; authored the books The Origins of Life (1972) and Cosmic Evolution, with George B. Field and Gerrit L. Verschuur (1978); and edited the books Limits of Life, with Lynn Margulis (1980), and Cometsand the Origin of Life (1981). Ponnamperuma suffered cardiac arrest in his office and died shortly thereafter at Washington Adventist Hospital in Washington, D.C.

For further information on Ponnamperuma see Jacques Cattell Press, ed., American Men and Women of Science: The Physical and Biological Sciences, vol. 5, 14th ed. (1971); Current Biography Yearbook (1995); and Emily J. McMurray, ed., Notable Twentieth-Century Scientists, vol. 3 (1995). An obituary is in the New York Times (24 Dec. 1994).

Maria Pacheco