Word: bacterium
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Dates: during 1980-1989
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...farming community of Tulelake, Calif., scientists in canary yellow overalls clambered aboard a tractor last week and began what looked like a workaday farmyard chore. They were planting ordinary potatoes, 2,000 tubers in all, that had been treated with an extraordinary additive: a genetically altered bacterium designed to inhibit the formation of frost. This experiment -- and a similar one performed only five days earlier -- marked a turning point in the efforts of scientists to apply the advances of recombinant DNA technology to agriculture: the first authorized release of man-made microbes into the environment...
...more dramatic previous test, 350 miles away in a Brentwood, Calif., strawberry field. There, technicians wrapped in head-to-foot "space suits" -- required by federal regulations governing airborne use of potentially toxic substances -- sprayed 2,400 strawberry plants with a slightly different strain of the same ice- inhibiting bacterium. The event drew a crowd of reporters and government officials, who arrived with elaborate devices to sniff the air and taste the dirt around the test site. The start of the experiment was delayed for an hour because of an act of sabotage: the night before, vandals, apparently expressing their disapproval...
...caused by a toxin-producing strain of the common bacterium, Staphylococcus aureus, carried benignly in the respiratory and genital tracts of perhaps one out of three people. Under certain conditions -- a wound, some infections, the presence of a tampon or contraceptive sponge -- the bacteria multiply. If the toxin-producing strain is present, such proliferation can lead to TSS. The symptoms are dramatic and develop quickly: high fever, a sunburn-like rash, severe vomiting and diarrhea, culminating in shock, in which blood pressure plummets and circulation deteriorates. Doctors usually try to head off this life-threatening condition by administering intravenous fluids...
...called luciferase -- produces light. But the process of collecting and grinding up fireflies to extract the enzyme was laborious and costly. She and Donald Helinski, a molecular geneticist, decided to isolate the luciferase gene, cloning exact copies of it and splicing it into the genetic machinery of the common bacterium E. coli. The E. coli could then massproduce luciferase by the vat. DeLuca and Helinski accomplished this task by using standard recombinant DNA techniques developed over the past 20 years and now widely employed in industrial microbiology laboratories...
...simplest available, might have been designed by Rube Goldberg. The luciferase gene was spliced to the regulatory switch of a gene belonging to a virus that infects plants. The altered two- part piece of DNA was then inserted into a circular strand of DNA, called a plasmid, from the bacterium Agrobacterium. The bacterial plasmid was incubated with tobacco-leaf cells, and the cells were nurtured into full-fledged plants...