Stanley Norman Cohen
Encyclopedia
Stanley Norman Cohen is an American
geneticist
.
Cohen is a graduate of Rutgers University
, and received his doctoral degree from the University of Pennsylvania
School of Medicine in 1960. Following subsequent training at various institutions, including the National Institutes of Health
, he joined the faculty of Stanford University
in 1968.
It was there that he began to explore the field of bacteria
l plasmid
s. He wanted to understand how the genes of plasmids could make bacteria resistant to antibiotic
s. Cohen's investigations in 1972, combined with those of Paul Berg
and Herbert Boyer
, led to the development of methods to combine and transplant genes. This discovery signaled the birth of genetic engineering
and earned Cohen the National Medal of Science
in 1988. He also co-authored (with Royston C. Clowes, Roy Curtiss
III, Naomi Datta
, Stanley Falkow
and Richard Novick) a proposal for uniform nomenclature for bacterial plasmids.
Today, Cohen is a professor of genetics and medicine at Stanford, where he works on a variety of scientific problems including cell growth and development.
and Herbert Boyer
made what would be one of the first genetic engineering
experiments, in 1973. They demonstrated that the gene
for frog
ribosomal
RNA
could be transferred into bacterial cells and expressed by them. First they constructed a plasmid
, which would be the vector, called pSC101
. This plasmid contained a single site for the restriction enzyme
EcoRI
and a gene for tetracycline resistance. The restriction enzyme EcoRI was used to cut the frog DNA into small segments. Next, the frog DNA fragments were combined with the plasmid, which had also been cleaved with EcoRI. The sticky ends of the DNA segments aligned themselves and were afterwards joined together using DNA ligase. The plasmids were then transferred into a strain of E. coli and plated onto a growth medium containing tetracycline. The cells that incorporated the plasmid carrying the tetracycline resistance gene grew and formed a colony of bacteria. Some of these colonies consisted of cells that carried the frog ribosomal RNA gene. The scientists then tested the colonies that formed after growth for the presence of frog ribosomal DNA. (Thieman, W.J and Palladino, M.A., Introduction to Biotechnology, Pearson Education, Benjamin Cummings, 2024. page 55)
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
geneticist
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
.
Cohen is a graduate of Rutgers University
Rutgers University
Rutgers, The State University of New Jersey , is the largest institution for higher education in New Jersey, United States. It was originally chartered as Queen's College in 1766. It is the eighth-oldest college in the United States and one of the nine Colonial colleges founded before the American...
, and received his doctoral degree from the University of Pennsylvania
University of Pennsylvania
The University of Pennsylvania is a private, Ivy League university located in Philadelphia, Pennsylvania, United States. Penn is the fourth-oldest institution of higher education in the United States,Penn is the fourth-oldest using the founding dates claimed by each institution...
School of Medicine in 1960. Following subsequent training at various institutions, including the National Institutes of Health
National Institutes of Health
The National Institutes of Health are an agency of the United States Department of Health and Human Services and are the primary agency of the United States government responsible for biomedical and health-related research. Its science and engineering counterpart is the National Science Foundation...
, he joined the faculty of Stanford University
Stanford University
The Leland Stanford Junior University, commonly referred to as Stanford University or Stanford, is a private research university on an campus located near Palo Alto, California. It is situated in the northwestern Santa Clara Valley on the San Francisco Peninsula, approximately northwest of San...
in 1968.
It was there that he began to explore the field of bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
l plasmid
Plasmid
In microbiology and genetics, a plasmid is a DNA molecule that is separate from, and can replicate independently of, the chromosomal DNA. They are double-stranded and, in many cases, circular...
s. He wanted to understand how the genes of plasmids could make bacteria resistant to antibiotic
Antibiotic
An antibacterial is a compound or substance that kills or slows down the growth of bacteria.The term is often used synonymously with the term antibiotic; today, however, with increased knowledge of the causative agents of various infectious diseases, antibiotic has come to denote a broader range of...
s. Cohen's investigations in 1972, combined with those of Paul Berg
Paul Berg
Paul Berg is an American biochemist and professor emeritus at Stanford University. He was the recipient of the Nobel Prize in Chemistry in 1980, along with Walter Gilbert and Frederick Sanger. The award recognized their contributions to basic research involving nucleic acids...
and Herbert Boyer
Herbert Boyer
Herbert W. Boyer is a recipient of the 1990 National Medal of Science, co-recipient of the 1996 Lemelson-MIT Prize, and a co-founder of Genentech. He served as Vice President of Genentech from 1976 through his retirement in 1991....
, led to the development of methods to combine and transplant genes. This discovery signaled the birth of genetic engineering
Genetic engineering
Genetic engineering, also called genetic modification, is the direct human manipulation of an organism's genome using modern DNA technology. It involves the introduction of foreign DNA or synthetic genes into the organism of interest...
and earned Cohen the National Medal of Science
National Medal of Science
The National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the fields of behavioral and social sciences, biology, chemistry, engineering, mathematics and...
in 1988. He also co-authored (with Royston C. Clowes, Roy Curtiss
Roy Curtiss
Roy Curtiss, III is a professor of Genomics, Evolution, & Bioinformatics at Arizona State University. He was elected to the United States National Academy of Sciences in 2001.-Education:...
III, Naomi Datta
Naomi Datta
Naomi Datta, FRS was a distinguished British geneticist. Working at Hammersmith Hospital in the 1950s and early 1960s she identified horizontal gene transfer as a source of multi-antibiotic resistance in bacteria....
, Stanley Falkow
Stanley Falkow
Stanley Falkow, PhD, is microbiologist and a professor of microbiology and immunology at Stanford University School of Medicine. He is sometimes referred to as the father of molecular microbial pathogenesis, which is the study of how infectious microbes and host cells interact to cause disease at...
and Richard Novick) a proposal for uniform nomenclature for bacterial plasmids.
Today, Cohen is a professor of genetics and medicine at Stanford, where he works on a variety of scientific problems including cell growth and development.
Experiment
Stanley Cohen, Paul BergPaul Berg
Paul Berg is an American biochemist and professor emeritus at Stanford University. He was the recipient of the Nobel Prize in Chemistry in 1980, along with Walter Gilbert and Frederick Sanger. The award recognized their contributions to basic research involving nucleic acids...
and Herbert Boyer
Herbert Boyer
Herbert W. Boyer is a recipient of the 1990 National Medal of Science, co-recipient of the 1996 Lemelson-MIT Prize, and a co-founder of Genentech. He served as Vice President of Genentech from 1976 through his retirement in 1991....
made what would be one of the first genetic engineering
Genetic engineering
Genetic engineering, also called genetic modification, is the direct human manipulation of an organism's genome using modern DNA technology. It involves the introduction of foreign DNA or synthetic genes into the organism of interest...
experiments, in 1973. They demonstrated that the gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
for frog
Frog
Frogs are amphibians in the order Anura , formerly referred to as Salientia . Most frogs are characterized by a short body, webbed digits , protruding eyes and the absence of a tail...
ribosomal
Ribosome
A ribosome is a component of cells that assembles the twenty specific amino acid molecules to form the particular protein molecule determined by the nucleotide sequence of an RNA molecule....
RNA
RNA
Ribonucleic acid , or RNA, is one of the three major macromolecules that are essential for all known forms of life....
could be transferred into bacterial cells and expressed by them. First they constructed a plasmid
Plasmid
In microbiology and genetics, a plasmid is a DNA molecule that is separate from, and can replicate independently of, the chromosomal DNA. They are double-stranded and, in many cases, circular...
, which would be the vector, called pSC101
PSC101
pSC101 is a DNA plasmid that is used as a cloning vector in genetic cloning experiments. pSC101 was the first cloning vector, used in 1973 by Herbert Boyer and Stanley Norman Cohen...
. This plasmid contained a single site for the restriction enzyme
Restriction enzyme
A Restriction Enzyme is an enzyme that cuts double-stranded DNA at specific recognition nucleotide sequences known as restriction sites. Such enzymes, found in bacteria and archaea, are thought to have evolved to provide a defense mechanism against invading viruses...
EcoRI
EcoRI
EcoRI is an endonuclease enzyme isolated from strains of E. coli, and is part of the restriction modification system.In molecular biology it is used as a restriction enzyme. It creates sticky ends with 5' end overhangs...
and a gene for tetracycline resistance. The restriction enzyme EcoRI was used to cut the frog DNA into small segments. Next, the frog DNA fragments were combined with the plasmid, which had also been cleaved with EcoRI. The sticky ends of the DNA segments aligned themselves and were afterwards joined together using DNA ligase. The plasmids were then transferred into a strain of E. coli and plated onto a growth medium containing tetracycline. The cells that incorporated the plasmid carrying the tetracycline resistance gene grew and formed a colony of bacteria. Some of these colonies consisted of cells that carried the frog ribosomal RNA gene. The scientists then tested the colonies that formed after growth for the presence of frog ribosomal DNA. (Thieman, W.J and Palladino, M.A., Introduction to Biotechnology, Pearson Education, Benjamin Cummings, 2024. page 55)
Awards
- 1980 Albert Lasker Award for Basic Medical ResearchAlbert Lasker Award for Basic Medical ResearchThe Albert Lasker Award for Basic Medical Research is one of the prizes awarded by the Lasker Foundation for the understanding, diagnosis, prevention, treatment, and cure of disease...
. - 1988 National Medal of ScienceNational Medal of ScienceThe National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the fields of behavioral and social sciences, biology, chemistry, engineering, mathematics and...
from President Reagan. - 1989 National Medal of TechnologyNational Medal of TechnologyThe National Medal of Technology and Innovation is an honor granted by the President of the United States to American inventors and innovators who have made significant contributions to the development of new and important technology...
. - 2004 Albany Medical Center PrizeAlbany Medical Center PrizeThe is the United States' highest value prize in medicine and biomedical research. Among prizes for medicine, the Albany Medical Center Prize is second only to the $1.4 million Nobel Prize in Medicine and the $1 million Shaw Price in life science and medicine....
(shared with Herbert BoyerHerbert BoyerHerbert W. Boyer is a recipient of the 1990 National Medal of Science, co-recipient of the 1996 Lemelson-MIT Prize, and a co-founder of Genentech. He served as Vice President of Genentech from 1976 through his retirement in 1991....
) - 2004 Shaw PrizeShaw PrizeThe Shaw Prize is an annual award first presented by the Shaw Prize Foundation in 2004. Established in 2002 in Hong Kong, it honours living "individuals, regardless of race, nationality and religious belief, who have achieved significant breakthrough in academic and scientific research or...
in Life Science and Medicine.