Word: outerness
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...derivative of a common inhabitant of the human intestine-lends itself to being engineered because its genetic structure has been so well studied. In the first step of the process, scientists place the bacterium in a test tube with a detergent-like liquid. This dissolves the microbe's outer membrane, causing its DNA strands to spill out in a disorderly tangle. Most of the DNA is included in the bacterium's chromosome, in the form of a long strand containing thousands of genes. The remainder is found in several tiny, closed loops called plasmids, which have only...
Returning to his laboratory at the University of Alabama Medical Center in Birmingham, Curtiss quickly hit on a way to keep E. coli under control. The microbes must be able to manufacture a protective membrane; without such an outer coat they would swell and burst during normal growth. To keep them from manufacturing a complete coat, Curtiss created an E. coli with a defect in a gene that makes diaminopimelic acid (DAP), an important ingredient of the membrane. The defect made the bugs dependent for their survival upon DAP supplied by scientists...
...more frustration awaited Curtiss: the mutants managed to survive and multiply even without DAP. How? Dennis Pereira, a graduate student who worked with Curtiss on the project, discovered that they were producing a sticky substance called colanic acid that held them together in the absence of their normal outer coat. By manipulating still another of the microbe's genes, Curtiss and Pereira deprived the bug of its ability to make colanic acid. That change provided an unexpected dividend; it also made the already sickly microbe extremely sensitive to ultraviolet light. Any exposure to sunlight would kill...
...varying figures, some of them just high-grade guesses. The problem is a serious obstacle to policymaking. For example, the U.S. Geological Survey-working from raw oil-company data and lacking funds to drill sufficient test holes-estimates that undiscovered resources of natural gas lying under water on the outer continental shelf may be as high as 655 trillion cu. ft., which at current consumption rates for gas would meet U.S. needs for more than 30 years. But then again, says USGS, the resources might be less than half that much. Lacking a better fix, energy planners cannot estimate...
...demonstrates how she keeps in shape with aquatic acrobatics, using plastic water wings. "I try to undulate like a sea anemone with them," she says. "When I wear them, I feel that I'm in a different world. It's kind of like floating around in outer space, only wetter...