Albert Claude Biography (1898-1983)
- cell biologist
Biologist Albert Claude received the Nobel Prize in 1974 for his discoveriesconcerning the fine structure of the cell. His early work described the nature of mitochondria as the powerhouse of the cell, paving the way for much groundbreaking research by others. In addition, he demonstrated that the interiorof cells were not merely an arbitrary mass of substances, but rather a highly organized space delineated by the net-like endoplasmic reticulum , a formation that he was the first to recognize.
Born in Longlier, Belgium (now Luxembourg), on August 24, 1898, Albert Claudechose to become a U.S. citizen at age 43. Though he maintained dual citizenship, his decision was the logical outcome of a growing research career in theUnited States, a place of opportunity for an individual who began life withwhat seemed like limited prospects. Claude's father, Florentin Joseph Claude,was a baker and unable to provide the kind of upbringing one might expect aNobel Prize winner to have had. His mother, Marie-Glaudicine Wautriquant, andhis father evidently provided the right attitude for young Claude, for he overcame the constraints of a limited education and poverty to gain acceptanceinto the University of Liege. This was possible because of his service in World War I, in which he won the Interallied Medal along with veteran status. The university admitted him under a special program designed for war veterans.
Claude earned an M.D. degree in 1928 under his continuing government scholarship and attended the Kaiser Wilhelm Institute in Berlin for further study. Herelocated to the United States in 1929 to join the staff of the RockefellerInstitute in New York City, home to much of the great biomedical research anddiscoveries of the early twentieth century. There Claude studied the tumor agent of Rous sarcoma, a virus of chickens. Though Claude had not been invitedto join the Institute, the director, Simon Flexner, one of the country's leading medical educators, approved his hiring.
In the laboratory of James B. Murphy , Claude began earnest work on isolatingthe originating factor of the sarcoma, a malignant plasma, first discoveredin 1911 at Rockefeller Institute by Peyton Rous, that was a type of soft-tissue cancer in chickens. Only recently had microbiologists first suggested that cancers might be caused by newly discovered agents known as viruses.But it was not until 1932 that Rous' work was vindicated by the discovery oftransmissible wild rabbit cancers that were proven to be viral in nature.
Diligently pursuing the new field of virology , Claude developed a techniqueusing a high-speed centrifuge to spin fractionated (broken-up) cells infectedwith viruses in an attempt to isolate their agents. Though his primitive machine was constructed from meat grinders and sieves, Claude was able to fractionate various components of cells that had never been separated before, paving the way for new understanding of their varying functions. Though he never succeeded in fully isolating the virus within the cell mixture (a developmentthat came years later by other investigators), his discoveries nevertheless became crucial to the study of cell biology.
The Rous virus is among those now known as a ribonucleic acid (RNA) virus, that is, its genetic material is derived from RNA rather than the more common deoxyribonucleic acid (DNA). Claude was surprised to find that it was not onlyvirus-infected cells that showed a high RNA content, but also healthy cells.By the early 1940s Claude joined forces with biochemists George Hogeboom andRollin Hotchkiss in an attempt to determine the origins of this cellular RNA.
Claude, Hogeboom, and Hotchkiss found a variety of different "granules" in the cells that they determined were mitochondria, which were first discovered in 1897. However, the purpose of these often abundant cell components, especially in the liver cells, still remained unknown. Claude found that the mitochondria were not the source of the cells' RNA, but they did harbor certain enzymes that seemed to be involved in the cells' energy metabolism, a process dimly understood at the time. Claude and his colleagues, in fact, proved in 1945that mitochondria are the "powerhouses" of all cells, from bacteria to liver, from plants to fungi to animals. The RNA, it turned out, was concentrated in other cell particles that fellow researcher George Palade discovered and called microsomes. Later renamed ribosomes, these particles were shown to be the centers of protein production in all cells of every type of living thing. In 1974 Claude, Palade, and a third researcher, Christian R. Duvé, shared the Nobel Prize for physiology or medicine.
By the early 1940s, Claude had significantly perfected ultracentrifugation (the process of separating cell particles) and was seeking other new technologies with which to probe the cell. In 1942 he became convinced that the newly developed electron microscope would be useful in furthering his studies and secured the use of the device at the Interchemical Corporation, home to the only electron microscope in New York City which was used primarily for metallurgical purposes.
The cells that Claude and his associate, Keith Porter , observed under the microscope showed the presence of a "lace-work" structure that was eventually proven to be the major structural feature of the interior of all but bacterialcells. This lace-work structure was also responsible in part for providing the shape of cells as well as the location for many granular cell components,including ribosomes. The discovery of this endoplasmic reticulum (derived from the Latin word for "fishnet") altered biologists' view of cells as simply bags of "stuff" to highly organized biological units.
In 1948 Claude returned to his native Belgium and for a time gave up active research to become an administrator at the Université Libre de Bruxelles, where he spent the next twenty years developing a significant cancer research center. During the same period he headed the Institut Jules Bordet, wherehe resumed research on the fine structure of cells.
In 1972 the Rockefeller University (formerly Institute) awarded Claude emeritus standing. Other honors accrued over the span of his career include the Medal of the Belgian Academy of Medicine, the Louisa G. Horowitz Prize of Columbia University, and the Paul Ehrlich and Ludwig Darmstaedter Prize of Frankfurt. In addition, Claude was a full member of the Belgian and French academiesof science and an honorary member of the American Academy of Arts and Sciences. Other honors included the Order of the Palmes Académiques of France, the Grand Cordon of the Order of Léopold II, and the Prix Fonds National de la Recherche Scientifique from Belgium.