Har Gobind Khorana was a scientist born in 1922 in India who made significant contributions to understanding how DNA encodes for protein synthesis. He helped decode the genetic code and was the first to synthesize a gene. For these achievements, he received the 1968 Nobel Prize in Medicine along with Marshall Nirenberg and Robert Holley. Khorana investigated many areas including protein synthesis, the genetic code, and artificial gene synthesis.

1. HAR GOBIND KHORANA

2. • Born on 9 January 1922
• Raipur Village Punjab
• Citizenship -United States
• Studied in Government College University, Lahore Punjab University (BS, MS)
• University of Liverpool (PhD)
• Known for First to demonstrate the role of nucleotides in protein synthesis
• Awards
• Nobel Prize in Medicine (1968)
• Gairdner Foundation International Award (1980)

3. Louisa Gross Horwitz Prize
ForMemRS (1978)
Albert Lasker Award for Basic Medical Research
Padma Vibhushan
Willard Gibbs Award (1974)
CONTRIBUTIONS
Har Gobind Khorana was a scientist who traversed boundaries, voth scientifically and
culturally.

4. • He helped in decipher how RNA encodes for the synthesis of protein,research that
earn him the Nobel Prize in Medicine with Marshall Nirenberg and Robert Holey in
1968.
• He made significant contributions to the science of PCR tests, which we use today to
look for SARS-COV-2 infections.
• In 1960s, Khorana confirmed Nirenberg’s findings that the way the four different
nucleotides are arranged on the spiral “ staircase” of DNA molecule determines the
chemical composition and function of a new cell.
• He also proved that the nucleotide code is always transmitted to the cell in group of
three called codons

5. • Also determines that some of the codons prompt the cell to start or stop.
• Khorana and Nirenberg awarded the Louisa Gross Horwitz award from University of Columbia in
1968.
• In 1970 he and his research team were able to synthesis the first artificial copy of a yeast gene.
• He investigated mutation in rhodopsin, a light sensitive protein found in the retina of vertebrate
eye and are associated with retinitis pigmentosa, which cause colour blindness.
• He read widely German language Chemistry and become curious about little known synthetic
reagents called carbodiimides that help form larger organic molecules from smaller
components.
• One of these chemicals in particular diccyclohexylcarbodiimides or DCC become critical in his
future work.

6. • He focussed on using DCC to synthesise complex molecules, wspecially protein
molecules called enzymes that govern metabolism.
• He succeeded in synthesising ATP, the molecule responsible for producing energy
in cells.
• By 1960,he had synthesized an even more complex molecule coenzyme A, which
involved in digestion.
• It is because the diccyclohexylcarbodiimides allows to string together DNA
sequences .
• Khorana moved to University of Wincons ini n at Madison in 1960.

7. • In 1961,biochemists Marshall Nirenberg and Heinrich Matthaei announced a way to
translate DNA sequences to amino acid sequences outside aliving cell.
• They first placed a variety of cell components in test tube then they introduced short
DNA sequences into test tube, the system translated them into sequence of
aminoacids and then to part of a protein.
• Khorana used DCC to create DNA sequence. Inserting synthesised sequences into a
tet tube could produce all the amino acid sequences that DNA encodes.
• Khorana worked around the clock in double shifts to solve the code first. By 1966 it
was complete

8. • Khorana and Nirenberg were awarded the Nobel Prize in 1968 for Medicine,
which they shared with Robert Holley, who had discovered another molecule
involved in protein formation.
• In 1979,Khorana moved his laboratory to Massachusetts Institute of Technology.
In 1972,he completed the total synthesis of a functional gene outside a living
organism.
• He also showed it could function appropriately in bacterium.