Word: bacterias
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Genetic engineering, an ensemble of techniques to join bits of DNA and insert them into bacteria to make large quantities of potentially valuable proteins, made a great splash last year when stock from Genentech Inc. went public and jumped $45 per share during its first day on the market. The slightest technological advance still sends prices leaping. Genentech jumped $7 in one day two weeks ago when workers announced a new process to make interferon, a supposed cancer-fighting protein. Genentech will now use yeast to produce the human protein rather than bacteria. It doesn't seem like a major...
There is, of course, nothing new in harnessing bacteria for human good. Microorganisms have long been used, even if unwittingly, to serve man's needs, from breaking down wastes to making alcohol and producing antibiotics. Man began interfering with the genes, at least indirectly, long before the 19th century
...scientists have access to their work. The ultimate safeguard: bacteria especially designed to self-destruct if they escaped the nurturing environment of the lab. Yet even without these precautions, subsequent tests showed that probably none of the doomsday scenarios could have occurred. Last year the NIH dropped most of the restrictions on gene-splicing work...
During normal bacterial reproduction, the cell simply divides, passing exactly the same genetic information on to each daughter cell. Thus they are natural clones, genetically identical to their single parent. In this kind of unisex reproduction, there is no chance for bacteria to inherit fresh characteristics that might help improve their chances of survival. But every so often two cells have a sort of sexual dalliance called conjugation. They approach each other, send out thin tubes that bring the cells together, and transfer genes. In the exchange, a bacterium may pick up, say, a gene for making an enzyme that...
Like Berg, Cohen wanted to insert new genes artificially into bacteria. But where Berg resorted to a virus as his transport system, Cohen opted for plasmids, which he had been studying in his lab. As he listened to Boyer's description of his work that night in Waikiki, however, Cohen realized that there might be a short cut. Boyer and his associates had found a so-called restriction enzyme that cuts DNA precisely at predetermined points, and performs this surgery in an especially helpful way: at each end of the severed, twin-stranded molecule, it leaves an extra...