Har Gobind Khorana

Har Gobind Khorana
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Name	Har Gobind Khorana
Birth date	9 January 1922
Birth place	Raipur, Punjab Province, British India
Death date	9 November 2011
Death place	Concord, Massachusetts
Nationality	Indian-born Canadian-American
Field	Biochemistry, Molecular biology, Genetics
Institutions	University of British Columbia, University of Wisconsin–Madison, Massachusetts Institute of Technology, Institute for Enzyme Research
Alma mater	University of Punjab, University of Liverpool, University of Cambridge
Known for	Genetic code elucidation, synthetic gene construction
Prizes	Nobel Prize in Physiology or Medicine, Wolf Prize in Medicine, Albert Lasker Award for Basic Medical Research

Har Gobind Khorana Har Gobind Khorana was an Indian-born Canadian-American biochemist and molecular biologist whose work on the genetic code and the synthesis of oligonucleotides transformed biology, genetics, biotechnology, and medicine. He shared the 1968 Nobel Prize in Physiology or Medicine for deciphering the triplet nature of the genetic code and later pioneered chemical synthesis of genes, influencing institutions such as Massachusetts Institute of Technology and industries including Genentech and Biogen.

Early life and education

Khorana was born in Raipur in the Punjab Province during British India and studied at local schools influenced by figures like Mahatma Gandhi-era social change and the politics of Punjab. He attended the University of Punjab for a BSc and MSc, then moved to the United Kingdom to study under researchers associated with University of Liverpool and University of Cambridge, interacting with work from laboratories connected to scientists such as Alec Bangham and contemporaries influenced by Sir Frederick Gowland Hopkins and Alexander Fleming. Khorana later emigrated to Canada to join the University of British Columbia and then moved to the United States to work at the Institute for Enzyme Research and University of Wisconsin–Madison, collaborating with scholars in the tradition of Arthur Kornberg and Severo Ochoa.

Scientific career and research

Khorana's early research at the University of British Columbia and University of Wisconsin–Madison addressed nucleotide chemistry and enzymology, building on foundations laid by Erwin Chargaff and Oswald Avery and advancing techniques used by Stanley Cohen and Herbert Boyer. At the Institute for Enzyme Research he studied transfer RNA and codon assignments, working in the same epoch as teams led by Marshall Nirenberg, Francesco Crick, and James Watson. Khorana's experiments using chemically synthesized polynucleotides confirmed the triplet codon hypothesis originally proposed by George Gamow and tested by Marshall Nirenberg and Heinrich Matthaei, enabling codon-to-amino-acid assignments for proline, glycine, and other amino acids, complementing work by Robert W. Holley on tRNA structure. Khorana developed methods for solid-phase synthesis and enzymatic ligation that paved the way for gene synthesis techniques later employed at Massachusetts Institute of Technology and by biotechnology companies like Genentech and Cetus Corporation. His lab produced the first completely synthetic gene, demonstrating functional expression in Escherichia coli and influencing research by Paul Berg, David Baltimore, and Harold Varmus. Khorana also contributed to studies of membrane proteins, drawing connections with research done at institutions such as Scripps Research and Rockefeller University.

Nobel Prize and major honors

In 1968 Khorana shared the Nobel Prize in Physiology or Medicine with Robert W. Holley and Marshall W. Nirenberg for interpretation of the genetic code and its function in protein synthesis, joining a list of laureates that includes Francis Crick and James Watson for earlier discoveries related to DNA. He subsequently received the Wolf Prize in Medicine, the Albert Lasker Award for Basic Medical Research, and honors from academies such as the Royal Society and the United States National Academy of Sciences. Khorana was awarded honorary degrees from universities including Harvard University, University of Oxford, University of Cambridge, University of Chicago, and Columbia University, and he held fellowships and memberships in societies like the Biochemical Society and American Academy of Arts and Sciences.

Personal life and legacy

Khorana married and maintained family ties while navigating academic moves across British India, the United Kingdom, Canada, and the United States, balancing roles comparable to other émigré scientists such as Subrahmanyan Chandrasekhar and Homi J. Bhabha in diaspora communities. He mentored generations of researchers who later joined faculties at institutions including MIT, Harvard Medical School, Stanford University, Yale University, Columbia University, and University of California, Berkeley. Khorana's legacy includes impacts on industrial research at Genentech and regulatory discussions involving agencies such as the National Institutes of Health and debates that informed policies at World Health Organization forums. His work is commemorated in collections at the Library of Congress and exhibitions at museums like the Smithsonian Institution.

Selected publications and discoveries

Khorana authored influential papers in journals associated with publishers like Nature, Science, and Proceedings of the National Academy of Sciences. Key publications reported the synthesis of oligonucleotides, assignment of codons, and construction of synthetic genes, milestones referenced alongside studies by Marshall W. Nirenberg, Robert W. Holley, Paul Berg, Arthur Kornberg, and Severo Ochoa. Representative topics include chemical synthesis techniques later refined by researchers at Cold Spring Harbor Laboratory and Max Planck Institute, experimental codon assignments paralleling work at National Institutes of Health laboratories, and the demonstration of gene expression in Escherichia coli systems used broadly by laboratories at University of Wisconsin–Madison and Massachusetts General Hospital.

Category:1922 births Category:2011 deaths Category:Nobel laureates in Physiology or Medicine Category:Indian biochemists Category:American molecular biologists