Efraim Racker (June 28, 1913 – September 9, 1991) was an
Austria
Austria, , bar, Östareich officially the Republic of Austria, is a country in the southern part of Central Europe, lying in the Eastern Alps. It is a federation of nine states, one of which is the capital, Vienna, the most populous ...
n
biochemist who was responsible for identifying and purifying Factor 1 (F1), the first part of the
ATP synthase enzyme to be characterised. F1 is only a part of a larger ATP synthase complex known as Complex V. It is a peripheral membrane protein attached to component Fo, which is integral to the membrane.
[Cox, Michael M. and David L. Nelson. Lehninger Principles of Biochemistry 4th Edition. New York: WH Freeman and Company. 2005]
Early life
Efraim Racker was born to a Jewish family in 1913 in
Neu Sandez,
Austrian Galicia
The Kingdom of Galicia and Lodomeria,, ; pl, Królestwo Galicji i Lodomerii, ; uk, Королівство Галичини та Володимирії, Korolivstvo Halychyny ta Volodymyrii; la, Rēgnum Galiciae et Lodomeriae also known as ...
), and grew up in
Vienna
en, Viennese
, iso_code = AT-9
, registration_plate = W
, postal_code_type = Postal code
, postal_code =
, timezone = CET
, utc_offset = +1
, timezone_DST ...
. His elder brother,
Heinrich Racker
Heinrich Racker (1910, Poland – 28 January 1961, Buenos Aires) was a Polish-Argentine psychoanalyst of Austrian-Jewish origin.R. Horacio Etchegoyen, 'Heinrich Racker (1910-1961)', ''International Dictionary of Psychoanalysis''Reprinted onlineat ...
, was to become a famous
psychoanalyst. Efraim Racker was studying medicine at the
University of Vienna
The University of Vienna (german: Universität Wien) is a public research university located in Vienna, Austria. It was founded by Duke Rudolph IV in 1365 and is the oldest university in the German-speaking world. With its long and rich hist ...
when Hitler invaded in 1938. Racker fled to Great Britain, where he took a job in a mental hospital in Wales. His research focused on the biochemical causes for mental diseases. During the war, Racker was given the opportunity to practice medicine, but he decided to move to the United States to continue his research.
[Kresge, Nicole, Robert D. Simoni and Robert L. Hill. "Unraveling the Enzymology of Oxidative Phosphorylation: The Work of Efraim Racker". Journal of Biological Chemistry Vol. 281, Issue 4. January 27, 2006. http://www.jbc.org/cgi/content/full/281/4/e4]
Career
In the U.S., he accepted a position as a research associate in physiology at the
University of Minnesota
The University of Minnesota, formally the University of Minnesota, Twin Cities, (UMN Twin Cities, the U of M, or Minnesota) is a public land-grant research university in the Twin Cities of Minneapolis and Saint Paul, Minnesota, United States. ...
in Minneapolis from 1941 to 1942. While investigating the biochemical basis for brain diseases, he discovered that the
polio
Poliomyelitis, commonly shortened to polio, is an infectious disease caused by the poliovirus. Approximately 70% of cases are asymptomatic; mild symptoms which can occur include sore throat and fever; in a proportion of cases more severe s ...
virus inhibited
glycolysis in the brains of mice. He eventually left his research position for a job as a physician at the
Harlem Hospital
Harlem Hospital Center, branded as NYC Health + Hospitals/Harlem, is a 272-bed, public teaching hospital affiliated with Columbia University. It is located at 506 Lenox Avenue in Harlem, Manhattan, New York City and was founded in 1887.
The hosp ...
in New York City. In 1944 he became an associate professor of
microbiology at the
New York University Medical School
NYU Grossman School of Medicine is a medical school of New York University, a private research university in New York City. It was founded in 1841 and is one of two medical schools of the university, with the other being the Long Island School of ...
, where he continued his work on glycolysis.
In 1952 he accepted a position at
Yale Medical School
The Yale School of Medicine is the graduate medical school at Yale University, a private research university in New Haven, Connecticut. It was founded in 1810 as the Medical Institution of Yale College and formally opened in 1813.
The primary te ...
, but left after two years to accept the position of chief of the Nutrition and Physiology Department at the
Public Health Research Institute of the City of New York. It was here that Racker demonstrated that glycolysis was dependent on ATPase and the continuous regeneration of ADP and phosphate. Maynard E. Pullam joined Racker's staff in 1953, and decided to uncover the mechanism of ATP synthesis in
mitochondria and
chloroplasts. Joined by Anima Datta and Harvey S. Penefsky, they set out to identify the enzymes used in ATP synthesis.
Racker left the Public Health Research Institute in 1966 to found the biochemistry department at
Cornell University
Cornell University is a private statutory land-grant research university based in Ithaca, New York. It is a member of the Ivy League. Founded in 1865 by Ezra Cornell and Andrew Dickson White, Cornell was founded with the intention to tea ...
. He continued his research at Cornell, and was awarded many honors and prizes, including the Warren Triennial Prize in 1974, the
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 scienc ...
in 1976, the Gairdner Award in 1980, and the America Society of Biological Chemistry's Sober Memorial Lectureship. In addition, he was appointed to 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 ...
and the
National Academy of Sciences.
Efraim Racker died in 1991, leaving colleague and friend Dr. Mossaad Abdel-Ghany to take care of his lab and graduate students, but not before coining the phrase, "Don’t waste clean thinking on dirty enzymes," which is often quoted as one of "The Ten Commandments of Enzymology".
Discovery
Racker and his associates, Anima Datta, Maynard Pullmand, and Harvey Penefsky, worked to isolate the enzymes involved in ATP synthesis. They observed that isolated mitochondrial fragments were capable of respiration but not able to synthesize ATP. Racker and his co-workers concluded that oxidative phosphorylation could be restored by addition of the supernatant from the
centrifuging. The complex making this restoration possible was named Factor 1 or F1 as it is a necessary coupling factor for ATPase activity. This discovery of the first enzyme of oxidative phosphorylation was identified and purified in 1960.
["Efraim Racker". Biographical Memoirs, Volume 70. National Academy of Sciences. 1996. http://www.nap.edu/readingroom/books/biomems/eracker.html]
The factor that binds F1 to the membrane, Fo, was discovered later in conjunction with Yasuo Kagawa. This particle was found to be sensitive to the antibiotic oligomycin and thus named Fo. This discovery had the added benefit of silencing any critics of the role of F1 in oxidative phosphorylation because it conferred oligomycin sensitivity on the ATPase activity complex.
Once both of these factors were identified Racker was able to confirm
Peter D. Mitchell
Peter Dennis Mitchell, FRS (29 September 1920 – 10 April 1992) was a British biochemist who was awarded the 1978 Nobel Prize for Chemistry for his discovery of the chemiosmotic mechanism of ATP synthesis.
Education and early life
Mitc ...
's hypothesis that contrary to popular opinion, ATP synthesis was not coupled to respiration through a high-energy intermediate but instead by a transmembrane proton gradient.
F1 is a critical part of ATP synthesis within the mitochondria. In its absence, Complex V is not able to create the proton gradient necessary to produce ATP.
It is responsible for coupling the
oxidation
Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a ...
of nutrients to the synthesis of ATP from ADP and inorganic phosphates.
On September 6, 1991, Racker was felled by a severe
stroke, and died in
Syracuse three days after.
References
External links
Biography-
The National Academies PressEfraim Racker, Scientist and Artist, June 28, 1913 - September 9, 1991 Cornell University LibraryEfraim Racker-Art Albums
{{DEFAULTSORT:Racker, Efraim
1913 births
1991 deaths
American biochemists
American medical researchers
Medical educators
Science teachers
Cornell University faculty
Yale School of Medicine faculty
American people of Polish descent
American people of Austrian-Jewish descent
Jews from Galicia (Eastern Europe)
Jewish American scientists
National Medal of Science laureates
Members of the United States National Academy of Sciences
Jews who immigrated to the United Kingdom to escape Nazism
20th-century American Jews
Austrian emigrants to the United States