research into the development of synthetic gene circuits, carefully designed combinations of genes that can be “loaded” into bacteria or other cells, directing their activity in much the same way that a basic computer program directs a computer. Such re-programmed bacteria might eventually serve in a wide variety of applications, including biocomputing, medical treatments, and environmental cleanup
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The research now, however, is in its very early stages, You said. So far, E. coli bacteria have been programmed to grow in numbers until a certain population size is reached. The bacteria then kill themselves off, growing again only after their numbers dwindle sufficiently.

The relatively simple program takes advantage of bacteria’s ability to communicate with one another, a process known as “quorum sensing,” and essential genetic pathways that control cell death.