Word: amino
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Dates: during 1960-1969
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Long before the three new Nobel laureates began their experiments, scientists had learned that the message of heredity is carried by large molecules of deoxyribonucleic acid (DNA) in the chromosomes. Researchers had deduced that somehow DNA directs the cells to assemble amino acids into the proteins that form the basic structural material of all living beings and impart their characteristics. Then, in 1953, James Watson (author of The Double Helix] and Francis Crick put together more of the puzzle; they discovered that DNA consists of twin helices that are held together by regularly spaced links similar to the stairs...
...dopamine, a natural body chemical essential to normal nerve activity in the midbrain. So, researchers reasoned, why not give the patients extra dopamine? The trouble is that dopamine cannot cross the natural barrier be tween the bloodstream and the brain to reach the deprived cells. But dopa, an amino acid that comes in three forms including L-dopa, crosses the barrier by a process not yet fully understood. It is broken down in the brain to yield the desired dopamine...
...last two decades scientists have found that DNA, a long double--chained molecule found in the nucleus, carries the cell's genetic information. This information is the blueprint that describes how the working parts of the cell, the proteins, should be assembled from 20 building blocks, the amino acids. Thus DNA ultimately determines the cell's function. The DNA's information is transferred to RNA (the cell's working manual), which is chemically like DNA except that it is usually single-stranded. Specific RNA messages ("messenger RNA") are shipped to the cytoplasm and there direct synthesis of the specific proteins...
...stopped the synthesis of all RNA by treating the cells with the specific antibiotic Actinomycin D, which is, incidentally, used to stop the growth of cancer cells. From then on, all protein synthesis depended on pre-existing messengers. He detected new protein molecules by exposing the cells to radioactive amino acids, which are incorporated into any protein the cell synthesizes. Kafatos has made thin sections of the cell and covered them with a thin photographic film. The radioactivity behaves like light and activated the film. His process is called autoradiography. He could then develop the film, count the activated silver...
...their onset. Months or even years before the physical signs appear, there are changes in mental processes. To Pauling, this suggests simply that the brain is more sensitive than most other organs to even a mild deficiency. He would broaden the range of "essential nutrilites" to include vitamins, amino acids and fatty acids, and probably a host of other substances. He would also widen the range of emotional illnesses for which biochemical causes, or at least components, should be sought...