Sunday, April 25, 2010

Gerard Henri de Vaucouleurs

Gerard de Vaucouleurs was born on April 25, 1918 in Paris, France. From an early age he was interested in astronomy, observing the moon from the balcony of his family's apartment using a marine telescope he had borrowed. A few years later his mother purchased a telescope for him and he used it to observe various stellar occulations, planetary conjunctions, an eclipse and with his small telescope he photographed close approaches by Mars to the Moon and the Pleiades star cluster.

De Vaucouleurs received a B.Sc. in 1936 from the Lycee Charlemagne in Paris and went to the Sorbonne from 1937-1939 for training in physics, astronomy and physics. Starting in 1939 de Vaucouleurs worked briefly at the private observatory of Julien Peridir, but after two months their association was interrupted by the outbreak of World War II. During the war De Vaucouleurs served as an artillery officer. In 1943 de Vaucouleurs re-enrolled at the Sorbonne to work on his doctoral degree, graduating 1949 after completing a dissertation on the molecular (Rayleigh) scattering of light in gases and liquids. In 1944 he married his first wife Antionette, who was also interested in astronomy.

De Vaucouleurs, interested in extragalactic astronomy did not see a future for himself in France, emigrated first to England where he ran a weekly science radio program for the BBC. The frequently cloudy skies of England led de Vaucouleurs to Australia, where he went to Australian National University in Canberra and in 1951 he got an appointment to the Mt. Stromlo observatory where he became the first research fellow at ANU to preform radial velocity studies of galaxies in the unexplored southern sky. He received a D.Sc. degree from ANU in 1957 for research in molecular physics, optics, photography, astronomy and astrophysics. In 1957 de Vaucouleurs emigrated to the United States where he took a position working at the Lowell Observatory, continuing his observations of galaxies and Mars. In 1958 he moved to Harvard where he planned a program of precise observations of Mars which were used for NASA's Mariner 9 program.

In 1960 de Vaucouleurs moved to the University of Texas at Austin, where he spent the next 35 years observing galaxies at the McDonald Observatory. It was after his move to Texas that de Vaucouleurs began producing his Reference Catalog of Bright Galaxies, the first in 1964, the second in 1976, and the third in 1991. These catalogs were a monumental effort to collect and homogenize all the basic data on 2599 bright galaxies. The observations used to produce these works led de Voucouleurs to believe that the value of the Hubble constant was about 100 km/s/mpc.

The Hubble constant (Ho) is a constant that relates the velocity (v) of a receding galaxy to the distance (d) from an observer. The Hubble law equation is: v=Hod. The law was first published in 1929 by Edwin Hubble who had noticed a relationship between the doppler redshift of spectrum lines and estimated distances from the Milky Way of receding galaxies. This law is an expression of the expansion of the universe. At the time of de Voucouleurs pronouncement, Allan Sandage and Gustav Tammann had presented a value for Ho of about 50. This dispute was unresolved for years and remained at the time of de Vaucouleurs death. Various methods have been used to estimate Ho and it is currently believed to be about 70.

De Vaucouleurs received many awards for his work, including the Herschel Medal from the Royal Astronomical Society in 1980 and the Henry Norris Russel Prize from the American Astronomical Society in 1988. He was became a member of the U. S. National Academy of Sciences in 1986.

De Vaucouleurs died on October 7, 1995.


Burbidge, Margaret; "Gerard de Vaucouleurs"; in Biographical Memoirs, Vol. 82, National Academy Press; 2003

Buta, Ronald; "Gerard Henri de Vaucouleurs, 1918-1995"; Bulletin of the American Astronomical Society(1996)28:1449-1450

Hubble's Law Wikipedia Entry

Sunday, April 18, 2010

George Herbert Hitchings

George Herbert Hitchings was born on April 18, 1905 in Hoquiam, Washington, the son of George Herbert Hitchings, shipbuilder and Lilian Matthews Hitchings. Although not well educated, his parents were avid readers and their thirst for knowledge was passed on to him. Hitching's father died when he was only twelve. Due to his family's wanderings Hitchings attended grade school Berkeley and San Diego, California and Bellingham, Washington. He completed his secondary education in Seattle, Washington, where he was class salutatorian.

In 1923 he entered the University of Washington and initially intending to be a pre-medical student, however the enthusiasm of the students and faculty of the chemistry department shifted his course to become a chemistry student. He finished his B.S. in 1927 and is M.S. in 1928. He then went to Harvard University, where he was assigned to work with Cyrus Fiske, whose group was studying analytical methods for studying purines and had detected and isolated adenosine triphosphate (for a brief review of purine chemistry see here). Hitchings finished his Ph.D. in 1933 and for the next nine years served in a variety of temporary positions including doing cancer research at the C. P. Huntington Laboratories at Harvard, doing nutrition research at the Harvard School of Public Health, and doing electrolyte research at Western Reserve University Medical School.

In 1942 Hitchings joined Burroughs Wellcome Research Laboratories (now GlaxoSmithKline), in Tuckahoe, New York as the head and sole member of the biochemistry department. At first his resources were limited and this allowed him to be free to develop his own methods of inquiry. In 1944 he hired Gertrude Elion as a laboratory assistant, beginning a life-long collaboration in drug research. They began investigating the way that purines and pyrimidines are synthesized and metabolized by human cells, bacteria and viruses. Inspired by the recent development of sulfa drugs, they began investigating other substances that could inhibit microbial growth by mimicking these nitrogen containing bases. Their research indicated that bacteria could not synthesize nucleic acids without the presence of certain purines in their growth media and this led them to investigate substances that would inhibit the incorporation of purines into their DNA.

DNA (and RNA) is made up of three components: nitrogen containing bases, deoxyribose (a five carbon sugar missing an oxygen on carbon 2, that in RNA is replaced by ribose) and phosphate. There are two different types of nitrogen containing bases which make up the part of the DNA that carries the information used to synthesize proteins: purines, which have a bicyclic structure composed of a six membered ring fused to a five membered ring, and pyrimidines which contain a six membered ring. adenine and guanine are the purines, and cytosine and thiamine are the pyrimidines that are found in DNA. The focus of Hitchings' research was to find a chemical analog of one of these bases which would inhibit the microbial enzymes which were responsible for synthesizing it's DNA. These nitrogen containing base analogs can also be used to inhibit the growth of cancer cells, which require them for their rapid growth.

In 1947 Hitchings began to receive financial assistance from the Sloan-Kettering Institute in exchange for providing compounds to be used in cancer treatment. Among the compounds that they developed for the treatment of cancer are diaminopurine, thioguanine and 6-mercaptopurine, which have all been used in the treatment of leukemia due to their ability to block the synthesis of DNA in white blood cells. They also developed azathioprine, a less toxic form of 6-mercaptopurine, which can be used to block the immune reaction after organ transplants and allopurinol, a drug used to treat gout by blocking the synthesis of uric acid, an end product of purine metabolism. Hitchings and Elion also developed zidovudine, which led directly to the development of AZT, one of the first drugs used to treat A.I.D.S.

In 1967 Hitchings became the vice president of research for Burroughs Wellcome and he retired and became a scientist emeritus in 1976. In 1968 he became director and in 1971 president of the Burroughs Wellcome Fund, a charitable foundation dedicated to funding medical research. He also served as director and vice president of The United Way and director and chairman of the American Red Cross. In 1988 he and Gertrude Elion (along with Sir James Black) were awarded the Nobel Prize for Physiology or Medicine. Other honors he received include the Gregor Mendel Medal from the Czechoslovakian Academy of Science in 1968 and the Albert Schweitzer International Prize for Medicine in 1989. He was awarded 11 honorary degrees and was made a member of the National Academy of Science.

Hitchings died on February 27, 1998.


Harvey, Robert C.; "Hitchings, George H." in American National Biography: Supplement 2 (American National Biography Supplement)
; Mark C. Carnes, Editor; Oxford University Press, 2005

Hitchings, George H., Nobel Prize Autobiography at

Kresge, Nicole, Simoni, Robert D., and Hill, Robert L.; "The Rational Design of Nucleic Acid Inhibitors to Treat Leukemia: The Work of George H. Hitchings"; The Journal of Biological Chemistry (2008) 283: e10

Sunday, April 11, 2010

Percy Lavon Julian

Percy Lavon Julian was born on April 11, 1899 in Montgomery, Alabama, the oldest of six children of a railway clerk and a school teacher. Learning was emphasized by his parents and his two brothers went on to become physicians and his three sisters received masters degrees. After elementary school he attended the State Normal School for Negros. Upon graduation he moved to Greencastle, Indiana, where he attended DePauw University. Because of his inadequate preparation he was admitted as a "sub-freshman" and in addition to his college classes he had to take classes at a nearby high school. He supported his education by working as a waiter and digging ditches.

Julian graduated from DePauw in 1920 as valedictorian of his class and a member of Phi Beta Kappa. After graduation, following the advice of his teachers, he took a position as a chemistry teacher at Fisk University in Nashville, Tennessee. He taught at Fisk for two years and in 1922 he won an Austin Fellowship that allowed him to go to Harvard University where in 1823 he received a M.A. Unable to continue at Harvard due to the color of his skin, joined the faculty at West Virginia State College. In 1928 he became the head of the chemistry department at Howard University in Washington D. C.

In 1929 Julian received a Rockefeller foundation grant that allowed him to travel to Vienna where he worked in the laboratory of Ernst Spath at the University of Vienna. In Vienna, Julian was able to finish his Ph.D. in 1931, working on natural products chemistry and completing a thesis on the alkaloids of the Corydalis cava. After finishing his Ph.D. Julian returned to Howard University, where he taught for two more years. In 1933 he returned to DePauw University as a research fellow. At DePauw, working with Joseph Pikl, a colleague of his from Vienna, Julian completed the total synthesis of physostigmine, a reversible inhibitor of cholinesterase. It is used to treat myasthenia gravis, glaucoma and Alzheimer's disease.

Frustrated because he was unable to obtain a faculty position at DePauw, Julian went into industry, where in 1936 he got a job as the director of research for soya products at Glidden in Chicago, Illinois. He worked at Glidden for 18 years developing products from soya beans which resulted in numerous patents including a paper coating and a fire retardant foam widely used during World War II. His research made possible the production of large quantities of steroid hormones such as progesterone and hydrocortisone at low cost. Around 1950 the Julian family moved from Chicago to Oak Park, Illinois. The first African-American family in the white neighborhood, their house was twice bombed. These attacks galvanized the community and a community group was formed to support the Julians

In 1953 he left Glidden and established Julian Laboratories, which specialized in producing synthetic cortisone. Using wild yams from Mexico, which he found were a better source of steroids than soya, Julian established Labratorios Julian de Mexico in Mexico city which cultivated the yams and shipped them to Oak Park, Illinois for refinement. In 1961 he sold the Oak Park plant to Smith, Kline and French for 2.3 million dollars.

Among the honors that Julian received was the Springham Medal from the NAACP and election to the National Academy of Science in 1973, as the second African-American to receive that honor.

Julian died on April 19, 1975.


Witkop, Bernhard, "Percy Lavon Julian" in Biographical Memoirs, Vol. 52, National Academy Press, 1980

"Percy Julian" at

Percy Lavon Julian, Wikipedia entry

Sunday, April 4, 2010

William Cumming Rose

William Cumming Rose was born on April 4, 1885 in Greenville, South Carolina. His father, John M. Rose was a Presbyterian minister and the family moved often. Rose attended a variety of local schools until he was 14 when his father removed him from school because it was not providing enough intellectual stimulation. Thereafter he was tutored by his father who introduced him to Greek, Latin, and Hebrew. He a acquired an interest in chemistry from reading Ira Remsen's An Introduction to the Study Chemistry, a textbook used by his sister. Rose wished to attend a large university, but his father, worried for his sixteen year old son, convinced him to attend Davidson College in North Carolina.

At 19 Rose obtained his B.S. degree and went to Yale University and the Sheffield Scientific School. There he studied biochemistry and worked as an assistant in the laboratory of Layfayette Mendel. In Mendel's lab he did a project on creatine/creatinine metabolism, which formed the basis of his doctoral thesis. He graduated in 1911.

After graduating he obtained a position as an instructor in physiological chemistry at the University of Pennsylvania. Then after a short time studying in Germany, in the laboratory of Professor Franz Knoop at the University of Freiburg, he accepted an appointment at the University of Texas, where he organized the first biochemistry course for medical students. He remained in Texas for nine years. In 1922 he went to the University of Illinois, as professor of physiological chemistry (the title was changed to professor of biochemistry in 1936). Rose remained at the University of Illinois until his retirement in 1955.

Although he was interested in many aspects of metabolism, Rose's work focused on amino acid metabolism and nutrition. Amino acids are the units which form proteins (For a review of amino acids see here). There are twenty different amino acids which animals and plants use to put together proteins. Some of these can be synthesized in vivo and a are called nonessential. Others that cannot be synthesized and must come from diet are called essential. In an experiment Rose fed rats with the nineteen amino acids known at the time as their sole source of nitrogen and the rats lost weight. Using the laborious isolation techniques available before chromatography, Rose and his colleagues where able to isolate the amino acid threonine, which when added to the rat's diet allowed them to gain weight.

Over the next twenty years Rose experimented to determine which amino acids were essential and nonessential for rats by excluding them from their diet. He determined that rats required nine essential amino acids (including threonine) in their diet and one, arginine, was only essential for optimal growth. In 1942 Rose began a similar set of experiments to determine which amino acids were essential for humans, using male graduate students as experimental subjects (an account of the experiment can be found here). The subjects urine and feces were examined to determine nitrogen balance. The experiments concluded that there were eight essential required in the human diet.

Rose served on the Food and Nutrition Board of the National Research Council and was instrumental on advising government agencies on nutritional requirements. From 1939 to 1941 Rose served as the president of the American Society of Biochemists. On his ninetieth birthday the William C. Rose Lectureship was established to honor biochemists for outstanding research into biochemistry and molecular biology and a commitment to training younger scientists. The William C. Rose award, as it was renamed, is given annually by the American Society for Biochemistry and Molecular Biology.

Rose died on September 15, 1985.


Carter, Herbert E. and Coon, Minor J.; "William Cumming Rose" at National Academy Press (

Roe, Daphne; "William Cumming Rose"; Journal of Nutrition (1981)111:1311-1320

Simoni, Robert D., Hill, Robert L., and Vaughan, Martha; "The Discovery of the Amino Acid Threonine: the Work of William C. Rose"; Journal of Biological Chemistry (2002) 277, e25