Paul Berg

Biochemist

• Born: June 30, 1926
• Birthplace: Brooklyn, New York
• Died: February 15, 2023
• Place of death: Stanford, California

Microbiologist and educator

Berg won the Nobel Prize in Chemistry in 1980 for his pioneering technique of splicing together deoxyribonucleic acid (DNA) from different types of organisms, which revolutionized the study of viral chromosomes and launched the field of genetic engineering.

Area of achievement: Science and technology

Early Life

Paul Berg was born to Sarah and Harry Berg on June 30, 1926, in Brooklyn. Paul Berg graduated from the New York City public schools in 1943 with a great interest in microbiology, fostered by Mrs. Wolf, a high school teacher who ran an after-school science club. Berg entered Pennsylvania State University in 1943, served in the US Navy from 1944 to 1946 and returned to school to graduate with a degree in biochemistry in 1948. He then moved to Case Western Reserve University in Cleveland, Ohio, graduating with a doctorate in biochemistry in 1952 and taking a yearlong American Cancer Society postdoctoral fellowship with Herman Kalckar at the Institute of Cytophysiology in Copenhagen, Denmark, and then a second fellowship with Arthur Kornberg at Washington University in St. Louis, Missouri. In 1956, he became an assistant professor of microbiology. He accepted the position of professor of biochemistry at Stanford University’s School of Medicine in 1959.

Life’s Work

Throughout the 1950s Berg patiently conducted a series of experiments to determine how amino acids, which combine to form proteins, join together. In 1956, he determined that a special molecule specifically joined the amino acid methionine to the ribonucleic acid (RNA) during replication. This molecule was one of a class of similar molecules, each specific to a unique amino acid that ultimately became known as transfer RNA (tRNA). His important discovery increased his interest in the study of genes, so he spent a sabbatical year in 1967 learning about deoxyribonucleic acid (DNA) tumor viruses at the Salk Institute with Renato Dulbecco. He returned to Stanford and began working with the monkey tumor virus SV40 to figure out how mammalian genes operate. Patient accumulation of data from many experiments enabled him to map out where on the DNA molecule the various viral genes occurred and the relationships among the various specific sequences of nucleotides in the genes and how they affect the DNA of the host organism that they infect. This information was important in ascertaining how cells became cancerous, that is, exhibit abnormal reproduction and growth.

Berg realized that he might be able to combine the DNA of the SV40 with the DNA of a bacteriophage (a type of virus) that would infect the intestinal bacterium Escherichia coli. In this way it would be possible to study a gene from one species in isolation from the usual set of genes with which it naturally interacted in its original host, since it was in another host that lacked such genes. This was the first time that anyone had artificially engineered at the genetic level what was in effect an organism possessing genes from two different organisms. Berg’s methodology also would enable scientists to quickly replicate particular proteins or other desirable materials using the second organism as a convenient host, a technique widely applied in agricultural, pharmaceutical, and chemical industries.

The problem with these newly created organisms was that they contained foreign genes, and the harmful effects of such artificial manipulation could not be reasonably predicted. This suggested to several scientists who were following these developments that caution should be exercised. A group of scientists in Boston first raised the issue. Berg published a letter in the July 26, 1974, issue of Science that listed a series of recommendations from a quickly convened Committee on Recombinant DNA Molecules Assembly of Life Sciences that Berg chaired for the National Academy of Sciences. It raised the possibility of the biological hazards posed by the new genetic engineering and called for a temporary moratorium on further work until such time as a meeting of experts could be assembled to “discuss appropriate ways to deal with the potential biohazards of recombinant DNA molecules.”

A group of 140 scientists with a few lawyers and science journalists gathered for a three-day meeting at the Asilomar Conference Center in Pacific Grove, California, on February 27, 1975, to take up these issues. A set of safeguards was created that was further refined by the Recombinant DNA Advisory Committee of the National Institutes of Health. Among many provisions was a requirement that special facilities be created for work with recombinant DNA to ensure that organisms undergoing genetic manipulation did not escape from laboratory facilities. Initially there was considerable controversy over these rules and their implementation on university and research campuses across the nation. Ultimately the standards for work with many organisms were relaxed, but certain pathogenic organisms require high standards of biosecurity. Berg became a professor emeritus at Stanford; he ceased conducting research in 2000 but still serves on many important advisory boards.

Significance

Berg’s work over many years to elucidate the biochemistry of nucleic acids, especially in regards to recombinant DNA, resulted in his winning the Nobel Prize in Chemistry in 1980 (with biochemists Walter Gilbert and Frederick Sanger), the Albert Lasker Basic Medical Research Award in 1980, the National Medal of Science in 1983, the Biotechnology Heritage Award in 2005, and numerous other awards. His careful attention to the ethical dimensions of his scientific work, motivated by a precautionary principle, has been heralded as a model for others to emulate. He chaired the advisory board of the Human Genome Project of the National Institutes of Health as well as numerous other important boards and panels over the years.

Bibliography

Berg, Paul. "Paul Berg—Biographical." NobelPrize.org. Nobel Prize AB, Mar. 2004. Web. 25 Apr. 2016.

Berg, Paul, and Maxine Singer. Dealing with Genes: The Language of Heredity. Herndon: University Science Books, 2008. Print.

Frederickson, Donald S. The Recombinant DNA Controversy: A Memoir. Science, Politics, and the Public Interest, 1974–1981. Washington, DC: Amer. Society for Microbiology, 2001. Print.

Morange, Michel. A History of Molecular Biology. Cambridge: Harvard UP, 1998. Print.

Wade, Nick. The Ultimate Experiment. New York: W. H. Freeman, 1977. Print.

Wright, Susan. Molecular Politics: Developing American and British Regulatory Policy for Genetic Engineering, 1972–1982. Chicago: U of Chicago P, 1994. Print.