Word: proteins
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Dates: during 1960-1969
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When a cell reproduces by division, the DNA molecules in its nucleus have two jobs. First they must make perfect duplicates of themselves. Then they must control the formation of enzymes (protein catalysts) that will generate the other proteins that the cell needs to grow bigger and split...
...difficulty was that the ACTH molecule is a protein, a long chain of amino acid groups linked together in a special sequence like a phrase in telegraphic code. If the code is not reproduced properly, synthetic ACTH will not do the magical things in the human body that natural ACTH does. Natural ACTH has 39 amino acid groups. Dr. Hofmann's synthetic copy has only 23, but this part of the chain seems to function biologically as well as the whole-somewhat as if a coded message were pruned of unnecessary words before being sent...
...chemical, nicknamed PAM, which proved an effective antidote to deadly nerve gases. Now his explanation of how nerves work offers insight into yet another obscure matter: how nerves are deadened by anesthesia. The discovery that such anesthetics as procaine and the Indian poison curare combine easily with the receptor protein, blocking the biochemical reaction, could lead to better anesthetics and more efficient drugs for treating disorders of the human nervous system. "One of the basic functions of human life is coming closer to being understood," said Dr. Nachmansohn...
...isolating a "receptor" protein, the Columbia biochemists proved that the same reaction that takes place at the synapse is repeated all along the length of the nerve. When a nerve is stimulated, a chemical called acetylcholine is released within the nerve. It combines with the receptor protein, causing an interchange of sodium and potassium ions. The ions in turn trigger release of more acetylcholine a bit farther along the line, letting the current advance. To turn off the signal, an enzyme, cholinesterase, is released that instantly destroys the acetylcholine in the nerve...
...reasons given by Dr. Katz for the widespread attacks is the general lack of protein in the diet of the people. Later studies of blood samples collected as part of the program will give further information about the causes, Dr. Katz noted...