Word: bacterias
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Most yachtsmen are eager to keep waterways clean and clear. They want to swim and fish over the side without encountering colon bacteria and other health hazards. And until recently, they never thought of themselves as polluters. Although the traditional marine "head" simply flushes wastes through the side of the boat and into the water, such sewage, thanks to nature's purifying processes, used to be only a modest problem in fresh waters and no problem at all in tide-flushed coastal waters...
...HONORS for making the breakthrough discovery went to a traditional bacteriologist. Taking purified DNA extracted from the chromosomes of dead pneumonia bacteria, Rockefeller Institute's Oswald T. Avery and his associates showed that it could transform other, normally harmless bacteria into virulent ones. The experiment indicated that it was DNA, and not protein, that carried the genetic message. So unexpected was that finding that even Avery was at first unwilling to accept it. Eight years later, Alfred Hershey and his assistant Martha Chase demonstrated that a virus' DNA could, by taking over a bacterium, also nullify the cell's genetic...
...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...
There is other evidence that the beginning of genetic surgery is not far off. Dr. Sol Spiegelman of Columbia University has synthesized an artificial virus that is indistinguishable from its natural model and has used it to infect bacteria and produce new viruses. He and his colleagues have little doubt that they will also eventually create "friendly" viruses and use them to cure disease rather than cause it?by using the viruses to stimulate the production of the chemical products upon which health and life itself depend...
Having eliminated various factors that might have accounted for the decay slowdown-such as a lack of oxygen or the presence of any substance with preservative qualities-the scientists decided to double-check and expand their findings by suspending marine bacteria and nutrients at even greater depths. They concluded that the rate of degradation is an average of "ten to 100 times slower in the deep sea." In the deep, they found, there seems to be "a general slowdown of life processes," probably due to the "combined effect of high pressure and low temperature." Alvin's sandwiches, for example...