Word: bacterias
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...other professional publications last June, was similar to hundreds of other pitches for drugs. Aimed at the doctors who write prescriptions, Lederle Laboratories' illustrated three-page spread implied, among other things, that Minocin is superior to all other available tetracyclines and effective against a strain of staphylococcus bacteria. Yet a follow-up ad, which ran in the same journals nearly three months later, was strikingly different. It quoted a statement by the U.S. Food and Drug Administration that the earlier claims were misleading. It also conceded that Minocin is a tetracycline variation with all the limitations of similar medications...
...researchers cannot yet explain exactly how such primitive "memories" work. But they believe that by studying the bacteria further, scientists may find important clues to the operation of much more complex systems in higher organisms, including...
...Bacteria are simple, single-cell organisms that lack the nervous systems and brains of higher life forms. Strange as it may seem, however, the little creatures have a rudimentary form of memory, according to two researchers at the Berkeley campus of the University of California. After performing an intriguing series of experiments, the scientists reported to the annual meeting of the American Chemical Society that the common intestinal bacterium Salmonella typhimurium can recall things in its past...
Biochemists Robert M. Macnab and Daniel Koshland were investigating a characteristic that S. typhimurium shares with many other bacteria: it responds strongly to changes in external stimuli. If, for instance, a hostile substance is introduced into its surroundings, the bacterium uses its flagella -long, hairlike appendages-to swim away from it. But if something attractive is placed near by-say, the sugar, glucose-it will move toward it. How the bacterium chooses its direction is still not fully understood, but it apparently makes its way on a trial-and-error basis. Tumbling to and fro, it senses that taking certain...
Studying this phenomenon, the biochemists decided to expose their subjects to two quite different environments in rapid succession. So complete was the changeover (accomplished in less than a second by a high-speed laboratory mixer) that the primitive bacteria should not have been able to detect the switch in surroundings. Yet, surprisingly, the bacteria were not fooled. Shifted from a highly favorable environment to a less desirable one, they began to tumble about in a wildly agitated way, apparently in search of those dimly remembered good surroundings. A short time later, this "memory" faded, and they resumed their normal, only...