Lafayette Benedict Mendel (February 5, 1872 – December 9, 1935) was an American
biochemist
Biochemists are scientists who are trained in biochemistry. They study chemical processes and chemical transformations in living organisms. Biochemists study DNA, proteins and cell parts. The word "biochemist" is a portmanteau of "biological ch ...
known for his work in
nutrition
Nutrition is the biochemical and physiological process by which an organism uses food to support its life. It provides organisms with nutrients, which can be metabolized to create energy and chemical structures. Failure to obtain sufficient ...
, with longtime collaborator
Thomas B. Osborne, including the study of
Vitamin A
Vitamin A is a fat-soluble vitamin and an essential nutrient for humans. It is a group of organic compounds that includes retinol, retinal (also known as retinaldehyde), retinoic acid, and several provitamin A carotenoids (most notably ...
,
Vitamin B,
lysine
Lysine (symbol Lys or K) is an α-amino acid that is a precursor to many proteins. It contains an α-amino group (which is in the protonated form under biological conditions), an α-carboxylic acid group (which is in the deprotonated − ...
and
tryptophan
Tryptophan (symbol Trp or W)
is an α-amino acid that is used in the biosynthesis of proteins. Tryptophan contains an α-amino group, an α-carboxylic acid group, and a side chain indole, making it a polar molecule with a non-polar aromatic ...
.
Life
Mendel was born in
Delhi, New York, son of Benedict Mendel, a merchant born in
Aufhausen
Aufhausen is a municipality in the district of Regensburg in Bavaria
Bavaria ( ; ), officially the Free State of Bavaria (german: Freistaat Bayern, link=no ), is a state in the south-east of Germany. With an area of , Bavaria is the largest ...
,
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwee ...
in 1833, and Pauline Ullman, born in Eschenau,
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwee ...
. His father immigrated to the
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...
from
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwee ...
in 1851, his mother in 1870.
["Lafayette Benedict Mendel."](_blank)
World of Biology. Farmington Hills, Mich.: Thomson Gale. 2006.
At 15, he won a New York State scholarship. Mendel studied classics, economics and the humanities, as well as biology and chemistry at
Yale University
Yale University is a private research university in New Haven, Connecticut. Established in 1701 as the Collegiate School, it is the third-oldest institution of higher education in the United States and among the most prestigious in the w ...
and graduated with honors in 1891.
He then began graduate work at the
Sheffield Scientific School
Sheffield Scientific School was founded in 1847 as a school of Yale College in New Haven, Connecticut, for instruction in science and engineering. Originally named the Yale Scientific School, it was renamed in 1861 in honor of Joseph E. Sheffiel ...
on a fellowship and studied
physiological chemistry under
Russell Henry Chittenden. He finished his
Ph.D. 1893 after only two years; his thesis topic was the study of the seed storage protein
edestin Edestin, (also known as Edistin) is a highly-digestible, hexameric legumin protein with six subunits, and a seed storage protein, with a molecular weight of 310 kDa. This protein is primarily found in hemp seeds. Edestin is a globular protein (bi ...
extracted from
hemp
Hemp, or industrial hemp, is a botanical class of '' Cannabis sativa'' cultivars grown specifically for industrial or medicinal use. It can be used to make a wide range of products. Along with bamboo, hemp is among the fastest growing plants ...
seed. Upon graduation, he began as an assistant at the Sheffield School in
Physiological chemistry. He also studied in
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwee ...
and was made an assistant professor on his return in 1896. He became a full professor in 1903 with appointments in the
Yale School of Medicine
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 ...
and the
Yale Graduate School as well as Sheffield.
With Chittenden, Mendel became one of the founders of the science of
nutrition
Nutrition is the biochemical and physiological process by which an organism uses food to support its life. It provides organisms with nutrients, which can be metabolized to create energy and chemical structures. Failure to obtain sufficient ...
. Together with longtime collaborator
Thomas B. Osborne he established
essential amino acids. As early as 1910 he found an important growth factor...later to be known as vitamin B. In 1903, at age 31, he was appointed full professor of physiological chemistry. In promoting Mendel, Yale made him one of the first high-ranking Jewish professors in the United States. Capping his illustrious career Mendel was appointed
Sterling Professor of Physiological Chemistry in 1921.
Of the twenty professors to be designated Sterling professors in the decade following their inception in 1920, only two were selected before Mendel. Of the twenty, Mendel was the only Jew.
Mendel wrote over 100 papers with Osborne of the
Connecticut Agricultural Experiment Station, where Mendel was also an appointee. In their early work, they studied the deadly poison
ricin
Ricin ( ) is a lectin (a carbohydrate-binding protein) and a highly potent toxin produced in the seeds of the castor oil plant, ''Ricinus communis''. The median lethal dose (LD50) of ricin for mice is around 22 micrograms per kilogram of bo ...
which is classified as a type 2
ribosome inactivating protein (RIP) from
castor beans. He was a member of the
Connecticut Academy of Arts and Sciences
The Connecticut Academy of Arts and Sciences is a learned society founded in 1799 in New Haven, Connecticut "to cultivate every art and science which may tend to advance the interest and happiness of a free and virtuous people." Its purpose is the ...
.
Vitamin A discovery
Mendel and Osborne's most important work involved the use of carefully controlled studies on
rats to study the necessary elements in a healthy diet. They discovered
Vitamin A
Vitamin A is a fat-soluble vitamin and an essential nutrient for humans. It is a group of organic compounds that includes retinol, retinal (also known as retinaldehyde), retinoic acid, and several provitamin A carotenoids (most notably ...
in 1913 in butter fat – independently discovered by
Elmer McCollum and
Marguerite Davis, who submitted their publication first, with both papers appearing in the same issue of the ''
Journal of Biological Chemistry
The ''Journal of Biological Chemistry'' (''JBC'') is a weekly peer-reviewed scientific journal that was established in 1905., jbc.org Since 1925, it is published by the American Society for Biochemistry and Molecular Biology. It covers research i ...
''
– as well as water-soluble
vitamin B in milk. They showed, for example, that a lack of Vitamin A in the diet led to
xerophthalmia
Xerophthalmia (from Ancient Greek "xērós" (ξηρός) meaning "dry" and "ophthalmos" (οφθαλμός) meaning "eye") is a medical condition in which the eye fails to produce tears. It may be caused by vitamin A deficiency, which is som ...
.
They also established the importance of
lysine
Lysine (symbol Lys or K) is an α-amino acid that is a precursor to many proteins. It contains an α-amino group (which is in the protonated form under biological conditions), an α-carboxylic acid group (which is in the deprotonated − ...
and
tryptophan
Tryptophan (symbol Trp or W)
is an α-amino acid that is used in the biosynthesis of proteins. Tryptophan contains an α-amino group, an α-carboxylic acid group, and a side chain indole, making it a polar molecule with a non-polar aromatic ...
in a healthy diet.
["Lafayette Benedict Mendel."Dictionary of American Biography, Supplements 1-2: To 1940. American Council of Learned Societies, 1944-1958. Reproduced in Biography Resource Center. Farmington Hills, Mich.: Thomson Gale. 2007.]
Mendel wrote many articles and published ''Changes in the Food Supply and Their Relation to Nutrition'' (1916) and ''Nutrition, the Chemistry of Life'' (1923).
Mendel married Alice R. Friend on July 29, 1917; they had no children. He died in 1935 of a heart condition after a long illness.
His house in
New Haven
New Haven is a city in the U.S. state of Connecticut. It is located on New Haven Harbor on the northern shore of Long Island Sound in New Haven County, Connecticut and is part of the New York City metropolitan area. With a population of 134,023 ...
is a
National Historic Landmark
A National Historic Landmark (NHL) is a building, district, object, site, or structure that is officially recognized by the United States government for its outstanding historical significance. Only some 2,500 (~3%) of over 90,000 places liste ...
.
Honors and awards
Mendel received many honors during his career. He was made
Sterling Professor
Sterling Professor, the highest academic rank at Yale University, is awarded to a tenured faculty member considered the best in his or her field. It is akin to the rank of university professor at other universities.
The appointment, made by the ...
at Yale in 1921. He was the first president of the American Institute of Nutrition. He was made a member of the
National Academy of Sciences
The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nat ...
in 1913. He won the
American Institute of Chemists Gold Medal
The American Institute of Chemists Gold Medal is the highest award of the American Institute of Chemists and has been awarded since 1926.
It is presented annually to a person who has most encouraged the science of chemistry or the profession of ...
in 1927 "for his outstanding contributions to chemistry". He won the Conné Medal of the Chemist's Club of New York in 1935 "for his outstanding chemical contributions to medicine".
References
{{DEFAULTSORT:Mendel, Lafayette B.
1872 births
1935 deaths
American biochemists
American people of German descent
Members of the United States National Academy of Sciences
People from Delhi, New York
Scientists from New Haven, Connecticut
Scientists from New York (state)
Vitamin researchers
Yale Sterling Professors
Yale School of Medicine faculty
Yale School of Engineering & Applied Science