Word: acidic
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Dates: during 1950-1959
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Most pre-evolutionists agree, said Dr. Calvin, that life first appeared something like 2 billion years ago when the earth's atmosphere was dominated by hydrogen compounds such as methane, ammonia and water vapor. Such simple organic compounds as acetic acid and glycine (an amino acid) are formed in the laboratory when ultraviolet light or electric sparks pass through such mixtures. Presumably, solar ultraviolet and natural lightning would do the same in nature...
...flat molecules produce layered structures, like playing cards scattered thickly on the floor. But they arrange themselves more neatly than cards do. Their edges tend to stick together, and thus the molecules build up into orderly stacks. The porphyrins do this, and so do the components of DNA (deoxyriboenucleic acid), the heredity-carrying substance that dominates life on earth...
Proteins are enormously complicated molecules, and until Sanger's work on insulin, no one had ever been able to determine the structure of even the simplest of them. Chemists have known for many years that protein molecules are made of amino acids (nitrogen-containing organic acids) strung together in long chains or cables. By various kinds of rough treatment, the chemists could separate and count the amino acid building blocks. But this did not reveal their structural plan...
...Sanger tried treating the insulin molecule gently, succeeded in breaking it into large chunks. He separated the fragments and labeled the amino acids on their ends by making them combine with a material called DNP (for dinitropheny). When he broke the fragments into smaller fragments, the amino acids that had been in the end positions were stained yellow with DNP. There are 51 amino acid units in insulin, a comparatively simple protein. But Sanger's patience and skill eventually found the place of each in the long chain. Then he reassembled the fragments and learned how the chain...
...Tips from Santa Claus. While London's more mannered newspapers either ignored Heuss editorially or muffled their welcome, Cassandra, the acid-veined columnist of the tabloid Daily Mirror (circ. 4.6 million), let fly: "Heuss has been marketed over here as a gentle, learned Santa Claus utterly removed from the Krupps, the Thyssens, the Schachts, and all the other industrialists and scientists without whose enthusiastic cooperation World War II would never have been possible . . . The President is, in fact, a skillful apologist for the German people." Cassandra was unmoved by Heuss's contribution...