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...1940s, however, the molecular biologists had come on the scene, and they insisted that fundamental life processes could be fully understood only on the molecular level. In their investigations, some used the electron microscope, which revealed details of structure invisible to ordinary optical instruments. Others specialized in X-ray crystallography, a technique for deducing a crystallized molecule's structure by taking X-ray photographs of it from different angles. Physicist Max Delbrück turned to nature for his investigative tools: bacteriophages (literally, "bacteria eaters"), tiny parasitic viruses that invade their host bacteria and rob them of their genetic heritage...
...steam-engine-development contract to a small firm in Newton, Mass., called Steam Engine Systems, or SES. Similar contracts to develop non-steam, low-pollution vapor engines using organic fluids like fluronol instead of water have gone to California's Aerojet-General Corp. and Thermo Electron of Waltham, Mass. The environmental agency expects to hold a competitive runoff by year's end to determine which of the three engines merits additional federal money...
...hind in a variety of fields. Japan and Europe are far ahead in establishing fast, new train networks and Mexico City has completed a subway system "that is both a great feat of engineering and a work of art." In high-energy physics, Italian scientists using a colliding-beam electron accelerator have come upon "what may be a new phenomenon in the creation of matter from energy, which seems to go beyond present physical theory." France, the Soviet Union and Switzerland are all at work testing the discovery on similar accelerators, but the U.S. has only one such machine...
Koshland's theory seems to provide the answer to the enigma. The reason that enzymes are so effective, he suggests, is that they hold a molecule's constituent atoms at the proper orientation for joining. By this "orbital steering," he explains, enzymes align the outermost electrons spinning around each atom so that they can readily be shared with other atoms. Such electron sharing is at the heart of all chemical reactions...
...holders," which are in effect chemical vises. After many attempts, they hit upon a holder that gripped the ethyl alcohol and acetic acid so that they were properly oriented for combination; thus when the molecules met, their reacting oxygen and carbon atoms were always at the correct angle for electron snaring-and the reaction took place a million times faster. By "steering" the individual atoms, Koshland concluded, the holder molecule had apparently duplicated the exact role of an enzyme...