Insights: In the Business of Synthetic Life; April 2005; Scientific American Magazine; by Sam Jaffe; 2 Page(s)

At first glance, the bacterial colonies that dot a petri dish in the Boston University laboratory of James J. Collins do not seem all that special. Each Escherichia coli bacterium has been genetically altered to manufacture a specific protein once the population density of the colony around it reaches a predefined level.

A skeptic might yawn. After all, genetic engineering isn't new. But these cells haven't just had a foreign gene spliced into them. Collins inserted a whole genetic network--he put in many genes that interact together as well as with the natural genetic machinery of the cell. In this case, he dropped in a quorum-sensing network from a Vibrio fischerii bacterium. If conventional genetic engineering is like changing the blade on a screwdriver, then Collins's approach is akin to altering the contents of the entire toolbox at once.