Word: proteins
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Dates: during 1930-1939
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...biological label, heavy nitrogen promises Lo be even more important than heavy hydrogen, since nitrogen is the characteristic constituent of protein foods and their constituent amino acids. With Dr. Urey's heavy hydrogen, Biological Chemist Rudolph Schoenheimer...
Some molecules are so small that they contain only one atom. Some are so large that they contain hundreds, thousands, possibly millions of atoms. Although they cannot be seen under the microscope, the giant, complex molecules of proteins are among the most important targets of current research in biological chemistry. Until recent years not much was known about them except that they were very big; that they contained carbon, hydrogen. oxygen, nitrogen and sometimes sulphur and phosphorus; that in such animal processes as digestion they were broken down by protein-wreckers called enzymes and that they were composed of polypeptide...
...whirling them in powerful ultracentrifuges. Stanley found that the virus which causes tobacco mosaic disease in plants is a huge molecule, which was weighed by Svedberg and Wyckoff at 17,000,000 times as much as a hydrogen atom. The virus of noninfectious rabbit warts was isolated as a protein molecule weighing 20,000,000 units...
...British Association for the Advancement of Science which got under way last fortnight at Nottingham (TIME, Sept. 13), and concluded its sessions last week, tidy, calm-browed Dr. Dorothy M. Wrinch of Oxford described her latest discoveries about the architecture of molecules. She showed a model of protein molecules which she had built after working them out mathematically. One typical globular molecule looked like a crocheted doily cut up and sewed together in a three-dimensional geometrical object. This she described as a "polyhexagonal lacelike pattern of atoms with the characteristic lacunae or holes, the whole forming a truncated tetrahedron...
...crystallized a typical virus (which causes mosaic diseases in tobacco plants) by chemical treatment; 3) that he had modified the virus molecule chemically and produced other types of plant disease; 4) that he had made the molecule inactive. All this proved, said Dr. Stanley, that "a virus is a protein molecule and as such may be regarded as non-living." The A. A. A. S. gave him a $1,000 prize for his work (TIME...