Word: bacterias
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...until the late 19th century, the "golden age of bacteriology," that scientists began to suspect the existence of some kind of infectious agents even smaller than the bacteria that were clearly visible through their microscopes...
Contaminated liquids that had been passed through porcelain filters designed to purify laboratory solutions and capable of blocking the passage of the smallest known bacteria were still able to infect both plants and test animals. However, careful microscopic scrutiny of the filtered liquids failed to reveal the "filterable agents" that caused the diseases. Also, unlike bacteria, these agents could apparently not be grown in culture dishes, where scientists hoped they might form colonies large enough to be seen with the naked eye. The source of such diseases as mumps, smallpox, yellow fever, rabies and dengue remained a mystery...
...clue to the activity of viruses emerged during World War I, when a British and a French scientist independently noticed the appearance of clear circular spots in laboratory cultures grown over with bacteria. When material from a clear spot was applied to a different location in the bacteria culture, another circular area devoid of bacteria soon appeared. Felix d'Herelle, the French bacteriologist, thought he knew why. "What caused my clear spots," he wrote, "was in fact an invisible microbe, a filterable virus, but a virus parasitic on bacteria." D'Herelle named the unseen bug a bacteriophage (from the Greek...
Ordinary microscopes provide sharp images of most bacteria but cannot distinguish anything smaller than about eight-millionths of an inch -- the tiniest bacteria, for example -- because the wavelength of visible light, which is in the hundred-thousandth of an inch range, is too long. Ruska found that a magnetic coil could focus electrons, which have a wavelength that is roughly 100,000 times shorter. Substituting magnets for lenses and electrons for light, he built his first electron microscope. Improved versions, by providing images of viruses and even large molecules, have revolutionized such disparate fields as biology and electronics...
...American friend, U.S. News & World Report Correspondent Nicholas Daniloff. This led the KGB to ask Goldfarb to invite Daniloff to his apartment, apparently so agents could plant documents on the reporter. Unlike another Soviet acquaintance of Daniloff's, Goldfarb refused. The KGB then raided Goldfarb's apartment, seized his bacteria collection and accused him of planning to take material "of national security importance" out of the country...