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Oswald Theodore Avery (October 21, 1877–1955) was a Canadian-born American physician and medical researcher. The major part of his career was spent at the Rockefeller Institute Hospital in New York City. Avery was one of the first molecular biologists and was a pioneer in immunochemistry, but he is best known for his discovery in 1944 with his co-workers Colin MacLeod and Maclyn McCarty, that DNA is the material of which genes and chromosomes are made.
Early life and career
Oswald Theodore Avery was born on 21 October 1877 in Halifax, Nova Scotia, the second of three sons of Elizabeth Crowdy and Joseph Francis Avery. A Baptist minister in England, Joseph Avery and his wife emigrated to Canada in 1873. Established as a well-respected pastor in Halifax, he moved his family to New York City in 1887, where he was appointed pastor of the Mariner's Temple Baptist mission church on the lower East Side. Each member of the family participated in the church: Elizabeth was involved with charities and the newsletter while young "Ossie" and his oldest brother, Ernest, often played clarinet on the church steps to attract new attendees. Ernest died early in 1892 at the age of eighteen, probably from tuberculosis. Several months later, Reverend Avery also died. Following their deaths, the then fifteen-year old Oswald assumed the paternal role for his youngest brother, Roy, a part he would also play some years later to his cousin, Minnie Wandell, whom Roy often affectionately referred to as "little sister."
After attending the New York Male Grammar School, Avery went to the Colgate Academy and then Colgate University, where he excelled in literature, public speaking, and debate. While at Colgate, he was a classmate of Harry Emerson Fosdick, who would become one of the most notable clergymen in America; it is likely that when Avery started at Colgate he also intended to enter the ministry. Avery received a BA in the humanities in 1900. For reasons that are not clear, and despite the absence of any scientific background, after college Avery chose a career in medicine and entered the College of Physicians and Surgeons in New York. He received his medical degree in 1904.
Desiring greater intellectual stimulation, and frustrated by his inability to help some of his patients, Avery moved in 1907 to laboratory work at the Hoagland Laboratory in Brooklyn, the first privately endowed bacteriological research institute in the United States. Since the laboratory was also associated with a Long Island hospital, Avery's duties included teaching student nurses. It was here that he acquired his best known and most enduring nickname, "The Professor," which was often affectionately shortened to "Fess." The Hoagland Laboratory's director, Benjamin White, instructed Avery in laboratory techniques and biochemistry. Avery initially worked on the bacteriology of yogurt, but soon developed an interest in tuberculosis after White suffered a severe case of the infectious pulmonary disease. It was during this time that Avery established what his biographer René J. Dubos called the pattern of his career, the "systematic effort to understand the biological activities of pathogenic bacteria through a knowledge of their chemical composition."
Avery received U.S. citizenship on August 1, 1918. He served as a captain in the U. S. Army Medical Corps from September 1918 until January 1919. In 1923 be bacame a faculty member at the Rockefeller Institute, where he worked until his retirement in 1948.
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Breakthrough discovery
For many years, genetic information was thought to be contained in cell protein. Continuing the research done by Frederick Griffith in 1928, Avery worked with MacLeod and McCarty on the mystery of inheritance. He had received emeritus status from the Rockefeller Institute in 1943, but continued working for five years, proving that not all breakthrough discoveries are achieved by younger people (by this time he was in his late sixties).
Their key experiment was simple in concept. Bacteria are able to transfer genetic material through a liquid medium to other bacteria, transforming (giving new genetic characteristics to) them. Therefore if bacteria transform when an organic molecule is placed in a liquid with them, then that molecule holds genetic information. For the experiment, a bacterium called a Pneumococcus was used. The R strain is harmless, while the S strain causes pneumonia in laboratory mice.
Substances were available to remove various organic compounds from bacteria, and if the remaining organic compounds were still able to cause R strain bacteria to transform then the substances removed couldn't be the carrier of genes. S strain bacteria first had the large cellular structures removed. Then they were treated with protease enzymes, which removed the proteins from the cells before the remainder was placed with R strain bacteria. The R strain bacteria transformed, meaning that proteins didn't carry the genes for causing the disease. Then the remnants of the S strain bacteria were treated with a deoxyribonuclease enzyme which removed the DNA. After this treatment, the R strain bacteria no longer transformed, as evidenced by mice not showing signs of pneumonia when injected with the bacteria. This indicated that DNA was the carrier of genes in cells.
Alfred Hershey and Martha Chase furthered Avery's research in 1952 with the Hershey-Chase experiment. These experiments paved the way for Watson and Crick's discovery of the helical structure of DNA, and thus the birth of modern genetics and molecular biology. Of this event, Avery wrote in a letter to his brother, "It's lots of fun to blow bubbles but it's wiser to prick them yourself before someone else tries to."
Nobel laureate Joshua Lederberg stated that Avery and his laboratory provided "the historical platform of modern DNA research" and "betokened the molecular revolution in genetics and biomedical science generally."
Avery retired to Nashville, Tennessee in 1949, and died there in 1955.
Biography
- René Dubos, The Professor, the Institute, and DNA: Oswald T. Avery, His Life and Scientific Achievements, 1976, Paul & Company, ISBN 0874700221
Collected papers
The collected papers of Avery are stored in two locations: the Tennessee State Library and Archives, and the Rockefeller Archive
Many of his papers and poems and hand written lab-notes are available through the National Library of medicine in the Oswald T. Avery Collection.
His most important paper where he shows that DNA is the substance that makes up the genes is available on line: Avery, Oswald T., Colin M. MacLeod, and Maclyn McCarty. Studies on the Chemical Nature of the Substance Inducing Transformation of Pneumococcal Types. Journal of Experimental Medicine 79, 2 (1 February 1944): 137-158.
1877 births | 1955 deaths | Geneticists | Molecular biologists | Haligonians | People from New York City
"Oswald Avery"