John Howard Northrop

Northrop was born in Yonkers, New York to John Isaiah, a zoologist and instructor at Columbia University who is a member of the Havemeyer family, and Alice Rich Northrop, 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 and Columbia University, where he earned his BA in 1912 and PhD in chemistry in 1915.^[3][4] During World War I, he conducted research for the U.S. Chemical Warfare Service on the production of acetone and ethanol through fermentation. This work led to studying enzymes.

In 1929, Northrop isolated and crystallized the gastric enzyme pepsin^[5] and determined that it was a protein. For this achievement, he was elected to the United States National Academy of Sciences in 1934.^[6] In 1938 he isolated and crystallized the first bacteriophage (a small virus that attacks bacteria), and determined that it was a nucleoprotein. He was elected to the American Philosophical Society that same year.^[7] Northrop also isolated and crystallized pepsinogen (the precursor to pepsin), trypsin, chymotrypsin, and carboxypeptidase.

For his 1939 book, Crystalline Enzymes: The Chemistry of Pepsin, Trypsin, and Bacteriophage, Northrop was awarded the Daniel Giraud Elliot Medal from the National Academy of Sciences.^[8] He was elected a Fellow of the American Academy of Arts and Sciences in 1949.^[9] Northrop was employed by the Rockefeller Institute for Medical Research in New York City from 1916 until his retirement in 1961. In 1949 he joined the University of California, Berkeley as Professor of Bacteriology, and later, he was appointed Professor of Biophysics.^[10]

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.^[11] Northrop committed suicide in Wickenburg, Arizona in 1987.^[12]

• Economos, A. C.; Lints, F. A. (1985), "Growth rate and life span in Drosophila V. The effect of prolongation of the period of growth on the total duration of life (J.H. Northrop, 1917) – revisited", Mech. Ageing Dev., vol. 33, no. 1 (published December 1985), pp. 103–113, doi:10.1016/0047-6374(85)90112-5, PMID 3908838, S2CID 23576391
• Herriott, R. M. (1981), "John Howard Northrop", J. Gen. Physiol., vol. 77, no. 6 (published June 1981), pp. 597–599, doi:10.1085/jgp.77.6.597, PMC 2215443, PMID 7021760
• Herriott, R. M. (1994), "John Howard Northrop: July 5, 1891 – May 27, 1987", Biographical Memoirs. National Academy of Sciences (U.S.), vol. 63, pp. 423–450, PMID 11615389

• See also this version of Northrop's National Academy of Science biography.

• Northrop, J. H. (1939), Crystalline Enzymes, Columbia University Press
• Shampo, M A; Kyle, R. A. (2000), "John Northrop – definitive study of enzymes", Mayo Clin. Proc., vol. 75, no. 3 (published March 2000), p. 254, doi:10.4065/75.3.254, PMID 10725951
• van Helvoort, T. (1992), "The controversy between John H. Northrop and Max Delbrück on the formation of bacteriophage: bacterial synthesis or autonomous multiplication?", Annals of Science, vol. 49, no. 6 (published November 1992), pp. 545–575, doi:10.1080/00033799200200451, PMID 11616207

• Works by or about John Howard Northrop at the Internet Archive
• John Howard Northrop on Nobelprize.org   including the Nobel Lecture on December 12, 1946 The Preparation of Pure Enzymes and Virus Proteins