Vickery, Hubert Bradford
VICKERY, HUBERT BRADFORD
Vickery was the second son of Edgar Jenkins Vickery, owner of a book and stationery shop, and of Mary Katherine Dudman. He spent his entire career at the Connecticut Agricultural Experiment Station as an investigator of the chemicals present in plants, particularly organic acids and amino acids, and their role in plant metabolism. His interest in chemistry began in the seventh grade, when his father presented him with a copy of Steele’s Fourteen Weeks in Chemistry. During his years at Yarmouth Academy he took all the science courses offered there and decided to become a chemist. At DaJhousie University he completed the rigorous honors course in chemistry in three years and became a high school science teacher in Halifax. That period came to an abrupt end in December 1917, when a munitions ship exploded in the harbor, damaging the school so badly that no teaching was possible for many weeks. In the meantime Vickery took an analytical position with Imperial Oil Company (1917–1919), doing commercial analyses.
Vickery obtained a science teaching position in the Provincial Normal School at Truro in 1919 while also doing research on water resources that earned him an M.S. at Dalhousie (1920). About this time Dalhousie called on him for emergency teaching when both of its chemistry teachers became incapacitated. His services were rewarded by an 1851 Exhibition scholarship that enabled him to undertake graduate studies in organic chemistry at Yale under Treat B. Johnson.
Through somewhat accidental circumstances Johnson loaned Vickery to Thomas B. Osborne of the Connecticut Agricultural Experiment Station for some chemical studies on proteins, particularly the distinction between peptide and amide nitrogen in protein hydrolysis. The report on this work was accepted as a dissertation for the Yale Ph.D., awarded by the chemistry department in 1922. Osborne then offered Vickery an assistant chemist position in the experiment station laboratory.
Since Osborne had been deeply involved for the last decade with nutrition studies in association with Yale’s Lafayette B. Mendel, studies that were shedding light on the role of trace organic materials (vitamins) in animal nutrition, Vickery’s first assignment was to isolate vitamin B from alfalfa leaves, known to be a rich source of the nutrient. Because of the rudimentary state of vitamin chemistry, the search was unproductive of its primary goal but initiated Vickery into a lifetime study of the chemistry of plant leaves.
During Vickery’s first two years in the station laboratory, he was associated with A. C. Chibnall, who was on a two-year leave from Imperial College in London. The two men, both interested in leaf proteins, learned techniques from each other and established a lifelong friendship. Methods of separating and purifying nitrogenous organic materials were still primitive and depended on use of heavy metal salts (mercury, lead, silver) and phosphotungstic acid as precipitants. By improving and refining prior techniques, Chibnall and Vickery made substantial progress in isolating and studying proteins, smaller nitrogenous compounds, and organic acids in leaves. Although both men soon went their separate ways, each became a recognized leader in plant chemistry, Chibnall in the field of waxes and Vickery in the area of nitrogenous intermediates in plant metabolism.
In his work on protein-free plant extracts in the 1920’s, Vickery showed free amino acids to be present in significant quantities, with asparagine generally dominant. Amino acids were also present as simple peptides. Other compounds of importance included purines, particularly adenine, in free form and as methylated bases such as stachydrine in alfalfa, choline in yeast, and nicotine in tobacco.
By 1928, when Osborne retired, it was decided that the alfalfa leaf had severe limitations and a decision was made to study tobacco, a plant with large leaves that were easily harvested without including masses of stems (as was the case with alfalfa). The leaf of the tobacco plant was the subject of intensive study during the next thirty years with the collaboration of Alfred J. Wakeman, Charles Leavenworth, George W. Pucher, and others at the station. An important aspect of the tobacco studies involved the development, with the aid of Chester Bliss, station statistician, of a statistically sound procedure for the sampling of leaves.
Vickery’s laboratory also made extensive studies on the metabolism, in leaves, of organic acids: citric, isocitric, malic, succinic, fumaric, and glycolic. Several of his associates developed new analytical methods for measurement of these acids, which were studied not only in illuminated plants but also in plants cultured partly in darkness.
Attention was also directed to nomenclature of amino acids, particularly the standardization of symbols used in the representation of the configuration of groups on asymmetric carbon atoms and the direction of optical rotation.
Still another area of activity was the history of chemistry, where Vickery contributed several studies of significance. The first was an investigation, with Osborne, of the succession of hypotheses dealing with the structure of proteins. This was followed by a study, with Carl Schmidt of the University of California, of the discovery of the several amino acids present in proteins.
From 1925 until his retirement in 1963, Vickery held an appointment on the Yale faculty and, each year, offered a course on the chemistry of proteins and amino acids. After retirement he remained involved in the activities of the Connecticut Agricultural Experiment Station, particularly in preservation of the historical specimens and records of the laboratory.
During World War II, Vickery was associated with the work of Edwin J. Cohn’s Plasma Fractionation Laboratory at Harvard. In 1946 he was one of the scientists invited by the U.S. Navy to observe the atomic bomb explosion at Bikini. He was a member of numerous scientific committees and received many honors, including election to the National Academy of Sciences (1943) and the American Academy of Arts and Sciences (1948).
Vickery was married three times: in 1916 to Vera Claire Heustis, who died in 1936; in 1938 to Mildred Raye Hobbs, who died in 1968; and in 1971 to Jeanette Opsahl.
I. Original Works. Much of Vickery’s research on plant chemistry was published in Journal of Biological Chemistry between 1922 and 1962. Works not published there include “A Review of Hypotheses of the Structure of Proteins,” in Physiological Review, 8 (1928), 395–446, with T. B. Osborne; “The History of the Discovery of the Amino Acids,” in Chemical Review, 9 (1931), 169–318, with C. L. A. Schmidt; “The Early Years of the Kjeldahl Method to Determine Nitrogen,” in Yale Journal of Biology and Medicine, 18 (1946), 473–516; “The Origin of the Word ‘Protein,’” ibid., 22 (1950), 387–393; and “A Chemist Among Plants,” in Annual Review of Plant Physiology, 23 (1972), 1–28, a scientific autobiography.
II. Secondary Literature. Israel Zelitch, “Hubert Bradford Vickery,” in Biographical Memoirs, National Academy of Sciences, 55 (1985), 473–504, includes a full bibliography of Vickery’s publications. See also McGraw-Hill Modern Men of Science, II (New York, 1968), 567–569.
Aaron J. Ihde