Har Gobind Khorana

Indian-born scientist

• Born: January 9, 1922
• Place of Birth: Raipur, Punjab, British India (now Pakistan)
• Died: November 9, 2011
• Place of Death: Concord; Massachusetts

• Pronunciation: hahr goh-BIHND koh-RAH-nuh

Har Gobind Khorana was an organic chemist best known for deciphering and elucidating the genetic code, and for synthesizing the first artificial gene. Khorana, along with Marshall W. Nirenberg and Robert W. Holley, was awarded the Nobel Prize in Physiology or Medicine in 1968. His work significantly advanced the general scientific conception of many biological processes.

Areas of achievement: Science, technology

Early Life

Har Gobind Khorana was born on January 9, 1922, to Shri Ganput Rai Khorana and Shrimat Krishna Devi Khorana in the village of Raipur in Punjab, British India, which is now in eastern Pakistan. Both of Khorana’s parents were Hindu. The youngest of five children, he was homeschooled by his father, a taxation official in the British-Indian government, but later attended D. A. V. Multan High School. Khorana attended Punjab University in Lahore, where he received a BS in chemistry in 1943 and an MS in 1945. An Indian government fellowship allowed him to enroll in a doctoral program at the University of Liverpool in England, where his research was supervised by Roger J. S. Beer.

He received a PhD in organic chemistry in 1948, having studied the structure of violacein, a bacterial pigment. Immediately following the completion of his PhD, Khorana conducted postdoctoral studies at the Eidgenössische Technische Hochschule (Federal Institute of Technology) in Zurich, Switzerland, until 1949. He returned to India for a short time, but in the wake of the partition of the province of Punjab between India and Pakistan, he could not find a job. Thus, he applied for and received a Nuffield Fellowship, which allowed him to study proteins and nucleic acids at the University of Cambridge with G. W. Kenner and Alexander R. Todd.

Life’s Work

In 1952, Khorana accepted the position of director in the organic chemistry section of the British Columbia Research Council at the University of British Columbia in Vancouver, Canada. There, he joined a research group interested in studying nucleic acids and phosphate esters, and with John G. Moffatt he synthesized coenzyme A, an accomplishment that won Khorana international acclaim. While at the University of British Columbia, he began to work on the synthesis of short polymers of nucleotides. Also in 1952, Khorana married Esther Elizabeth Sibler, with whom he had three children.

In 1960, Khorana accepted a position as professor and codirector of the Institute for Enzyme Research at the University of Wisconsin–Madison. In 1966, Khorana became a naturalized citizen of the United States. Khorana accepted the position of Alfred P. Sloan Professor of Biology and Chemistry at the Massachusetts Institute of Technology (MIT) in 1970. From 1974 to 1980, while still at MIT, Khorana served as the Andrew D. White Professor-at-Large at Cornell University. Khorana retired from MIT in 2007.

Khorana is best known for his work in explaining the operation of the genetic code—the structure of the nucleic acids (DNA and RNA) that control all the inherited traits of living organisms. Specifically, Khorana and his colleagues figured out how the chemical structure of nucleic acids controls the synthesis of the thousands of kinds of proteins involved in the operations of living cells. Khorana’s work began in 1960 while he was at the University of Wisconsin and complemented the work of Marshall W. Nirenberg at the National Institutes of Health. Nirenberg was the first person to synthesize a simple nucleic acid, which was used to produce a corresponding protein, showing that the one “translated” into the other. Khorana’s expertise in chemical synthesis allowed him to synthesize more and larger nucleic acids over the next five years—crucial steps in the final “cracking” of the genetic code by mid-decade, for which Nirenberg, Khorana, and Robert W. Holley shared a Nobel Prize in 1968.

After his work on the genetic code, Khorana continued working on the chemical synthesis of DNA, contributing greatly to methods for synthesizing artificial genes used widely in biotechnology in the twenty-first century. Khorana authored over five hundred publications during his career. In 1966, he was elected to the National Academy of Sciences. Khorana was the recipient of numerous awards and honors in addition to the Nobel Prize, including the Albert Lasker Basic Medical Research Award in 1968 and the National Medal of Science in 1987. He held numerous honorary degrees.

Significance

Deciphering the genetic code was a scientific triumph that has had a profound impact on science’s understanding of many biological processes. The work of Khorana and others on the genetic code elucidated the mechanism of the transfer of information contained in DNA and RNA to the amino acid sequences that make up proteins. Khorana’s work confirmed many of the attributes of the genetic code originally envisioned by molecular biologist Francis Crick, led to an understanding of how mutations affect the structure of proteins, and has contributed to the development of many pharmaceuticals. His work greatly modernized the field of molecular biology and raised its profile in modern science.

Bibliography

Bansal, Kamna. "Unraveling the Genetic Code: The Legacy of Har Gobind Khorana (January 9, 1922, to November 9, 2011)." Cureus, vol. 16, no. 5, 2024, 10.7759/cureus.60048. Accessed 20 Aug. 2024.

Doughty, Danielle. "Biographical Memoir Published on Har Gobind Khorana, Nobel Laureate and Former Alfred P. Sloan Professor of Biology and Chemistry." Massachusetts Institute of Technology, 20 June 2024, chemistry.mit.edu/chemistry-news/biographical-memoir-published-on-har-gobind-khorana-nobel-laureate-and-former-alfred-p-sloan-professor-of-biology-and-chemistry/. Accessed 20 Aug. 2024.

Jones, Phillip. The Genetic Code. New York: Chelsea, 2010. Print.

Khorana, H. Gobind. Chemical Biology: Selected Papers of H. Gobind Khorana. Singapore: World Scientific, 2000. Print.

---. “Essays on Science and Society: A Life in Science.” Science 287.545 (Feb. 2000): 810. Science/AAAS. Web. 20 Jan. 2012.

Reichard, P. “Award Ceremony Speech.” 1968. Nobelprize.org. Nobel Media, 2012. Web. 23 Feb. 2012.