Word: amino
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Dates: during 1960-1969
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...central problem of protein chemistry, one that can be solved only by X-ray analysis. Until 1953 such analysis, however, had proved fruitful only when used to determine the atomic arrangement of simple organic compounds at least a hundred times smaller than protein molecules, which contain hundreds of amino acid residues arranged in definite sequences as polypeptide chains...
...they reveal that hemoglobin contains four polypeptide chains of roughly equal length, identical in pairs, and structurally complementary. Both hemoglobin and myoglobin have polypeptide chain folds; this characteristic tertiary structure may be fully determined by their amino acid sequence...
...others ferreted out the detailed structure of ACTH by complex and exquisitely delicate analytic processes. Then he set out to duplicate nature, or even improve on it. by making ACTH in the laboratory. The natural hormone contains 39 amino acids in a chain. Dr. Li made chains of 17 and 19 acids, and in some ways those short chains are almost as potent as the whole natural hormone; in other ways they are still more potent...
...difficulties of synthesizing the hormone promise to be immense; HGH, which contains 256 amino acids, is far more complex than ACTH. But Dr. Li is learning more about it with every experiment. Most recently, he injected HGH into a female monkey, causing her to give milk, even though she had not been pregnant. Now Dr. Li is convinced that the hormone does double duty, controlling not only human growth but almost certainly lactation as well...
...Schramm started his synthesis with chemicals that were probably dissolved in the ancient ocean before life appeared. Some of them were simple sugars, amino acids or nucleotides (small molecules contained in nucleic acids). Perhaps the most important were phosphorus compounds called polyphosphate esters. Dr. Schramm believes that all of them could have been formed by natural, nonliving reactions on the lifeless earth...