John Howard Northrop (July 5, 1891 – May 27, 1987) was an American biochemist who, with James Batcheller Sumner and

Wendell Meredith Stanley Wendell Meredith Stanley (16 August 1904 – 15 June 1971) was an American biochemist, virologist and Nobel laureate. Biography Stanley was born in Ridgeville, Indiana, and earned a BSc in Chemistry at Earlham College in Richmond, Indiana. ...

, won the 1946

Nobel Prize in Chemistry ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then "M ...

. The award was given for these scientists' isolation, crystallization, and study of

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...

s, proteins, and viruses. Northrop was a Professor of Bacteriology and Medical Physics, Emeritus, at

University of California, Berkeley The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant u ...

Biography

Early years

Northrop was born in

Yonkers, New York Yonkers () is a city in Westchester County, New York, United States. Developed along the Hudson River, it is the third most populous city in the state of New York, after New York City and Buffalo. The population of Yonkers was 211,569 as en ...

to John Isaiah, a

zoologist Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the animal kingdom, including the structure, embryology, evolution, classification, habits, and d ...

and instructor at Columbia University who is a member of the Havemeyer family, and

Alice Rich Northrop Alice Rich Northrop (March 6, 1864 – May 6, 1922) was an American botanist. She was known for expanding access to nature for New York City's public school children. Northrop traveled extensively to regions of the world where women did not usual ...

, a teacher of botany at Hunter College. His father died in a lab explosion two weeks before John H. Northrop was born. The son was educated at

Yonkers High School Yonkers Middle High School is located in Yonkers, New York, United States. The school offers the International Baccalaureate program. Yonkers High School was ranked the 24th best American high school and the 4th best New York State high school in ...

and

Columbia University Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manhatt ...

, where he earned his BA in 1912 and PhD in chemistry in 1915. During

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

, he conducted research for the U.S. Chemical Warfare Service on the production of

acetone Acetone (2-propanone or dimethyl ketone), is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile and flammable liquid with a characteristic pungent odour. Acetone is miscib ...

and

ethanol Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a ...

through fermentation. This work led to studying enzymes.

Research

In 1929, Northrop isolated and crystallized the gastric enzyme

pepsin Pepsin is an endopeptidase that breaks down proteins into smaller peptides. It is produced in the gastric chief cells of the stomach lining and is one of the main digestive enzymes in the digestive systems of humans and many other animals, w ...

and determined that it was a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...

. In 1938 he isolated and crystallized the first bacteriophage (a small virus that attacks

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of prokaryotic microorganisms. Typically a few micrometr ...

), and determined that it was a

nucleoprotein Nucleoproteins are proteins conjugated with nucleic acids (either DNA or RNA). Typical nucleoproteins include ribosomes, nucleosomes and viral nucleocapsid proteins. Structures Nucleoproteins tend to be positively charged, facilitating int ...

. Northrop also isolated and crystallized pepsinogen (the precursor to pepsin),

trypsin Trypsin is an enzyme in the first section of the small intestine that starts the digestion of protein molecules by cutting these long chains of amino acids into smaller pieces. It is a serine protease from the PA clan superfamily, found in the d ...

, chymotrypsin, and

carboxypeptidase A carboxypeptidase ( EC number 3.4.16 - 3.4.18) is a protease enzyme that hydrolyzes (cleaves) a peptide bond at the carboxy-terminal (C-terminal) end of a protein or peptide. This is in contrast to an aminopeptidases, which cleave peptide bonds ...

. For his 1939 book, ''Crystalline Enzymes: The Chemistry of Pepsin, Trypsin, and Bacteriophage'', Northrop was awarded the

Daniel Giraud Elliot Medal The Daniel Giraud Elliot Medal is awarded by the U.S. National Academy of Sciences "for meritorious work in zoology or paleontology study published in a three- to five-year period." Named after Daniel Giraud Elliot, it was first awarded in 1917. ...

from the National Academy of Sciences. He was elected a Fellow of the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, a ...

in 1949. Northrop was employed by the

Rockefeller Institute for Medical Research The Rockefeller University is a private biomedical research and graduate-only university in New York City, New York. It focuses primarily on the biological and medical sciences and provides doctoral and postdoctoral education. It is classi ...

in New York City from 1916 until his retirement in 1961. In 1949 he joined the

as Professor of Bacteriology, and later, he was appointed Professor of Biophysics.

Personal life

In 1917, Northrop married Louise Walker (1891–1975), with whom he had two children: John, an oceanographer, and Alice, who married Nobel laureate Frederick C. Robbins. The family lived in a small home just outside of Mt. Vernon, New York. As their children grew older and Northrop looked for a more desirable workplace, the family bought a home in Cotuit, Massachusetts. This move shortened Northrop's commute to the laboratory in Princeton, New Jersey, and also put him in closer contact with the wilderness which he greatly enjoyed. Northrop committed suicide in

Wickenburg, Arizona Wickenburg is a town in Maricopa and Yavapai counties, Arizona, United States. As of the 2020 census, the population of the town was 7,474, up from 6,363 in 2010. History The Wickenburg area, along with much of the Southwest, became part ...

in 1987.See p. 440 of

References

External links

* * including the Nobel Lecture on December 12, 1946 ''The Preparation of Pure Enzymes and Virus Proteins'' {{DEFAULTSORT:Northrop, John Howard 1891 births 1987 suicides 20th-century American chemists American Nobel laureates Columbia University faculty Columbia College (New York) alumni Nobel laureates in Chemistry People from Yonkers, New York Suicides in Arizona Rockefeller University people People from Wickenburg, Arizona American people of German descent Fellows of the American Academy of Arts and Sciences Members of the United States National Academy of Sciences Medical physicists Scientists from New York (state) University of California, Berkeley faculty 1987 deaths Havemeyer family Columbia Graduate School of Arts and Sciences alumni