Rose entered graduate school at the age of 19 when he enrolled in the
Sheffield Scientific School at Yale. Four years later he received his
Ph.D. under L. B. Mendel with a study that was part of a series on the
origin of creatine and creatinine. Rose occupied several academic posts
before accepting a position at the University of Texas Medical School
in Galveston where he organized a department of biochemistry. In 1922
Rose moved to the University of Illinois as professor of physiological
chemistry. In 1936 the title was changed to professor of biochemistry.
Until his retirement in 1955 Rose trained many future biochemists in addition
to his work as a pioneer in biochemistry and nutritional science.
Rose displayed a gift as a researcher for meticulous experimentation.
His early work on creatine and its dehydration product, creatinine, dealt
with the role of carbohydrates in the metabolism of those compounds and
with the effect of inanition (the loss of vitality that results from the
lack of food and water) on the creatine content of muscle. In his continuing
research in this area Rose explored the metabolic relationship of creatine
to creatinine and of both to other nitrogenous substances.
In the 1930s Rose undertook experiments that introduced the idea of an
essential amino acid into nutrition in both human and rodent diets. Nutritionists
had known for a long time that rats fed on a diet in which the only protein
was zein, which is found in corn, would inevitably die. Rose worked with
the constituent amino acids rather than proteins. He still found, however,
that the rats died regardless of the combination of amino acids he tried.
But if the milk protein casein was added to their diet, the ailing rats
Rose concluded that casein must contain an unknown amino acid not found
in zein that was essential to life. In a long series of experiments extracting
and testing various fragments of casein, Rose discovered threonine, the
essential amino acid that provided a satisfactory diet for rodents when
added to other amino acids. In addition, Rose structurally analyzed threonine
and showed that it is not synthesized by the body but must be obtained
from the diet. Rose proved that different amino acids are essential for
Rose argued that if there were one essential amino acid, there could well
be others. Over the years, he manipulated the rodent diet to establish
the primary importance of ten amino acids: lysine, tryptophan, histidine,
phenylalanine, leucine, isoleucine, methionine, valine, and arginine in
addition to the newly discovered threonine.
In the 1940s Rose undertook a ten-year research project on the human diet,
including the nutritive properties of amino acids. Most significantly,
Rose investigated the role of proteins in metabolism and the metabolic
interrelationships among amino acids. This work led to the determination
of amino acid requirements for humans.
Rose received many honors during his long and productive life. He was
elected to the National Academy of Sciences in 1936 and received the National
Medal of Science in 1966. Davidson College, Yale University, the University
of Chicago, and the University of Illinois accorded Rose honorary doctor
of science degrees. Rose also received the Willard Gibbs Medal from the
American Chemical Society in 1952 and the Charles F. Spencer Medal, also
of the ACS, in 1957.