How genetic circuits will unlock the true potential of bioengineering
By Julius B. Lucks, Adam P. Arkin / March 2011 /IEEE Spectrum
In 1977, a small group of researchers in California changed the world when they wrangled a common gut bacterium into producing a human protein. Using every technique in the book—and inventing some of their own—they scavenged, snipped, and glued together genetic components to synthesize a tiny filament of DNA. They then inserted the new segment into some Escherichia coli cells, tricking them into making the human hormone somatostatin.
A year later, these scientists had an E. coli strain that produced insulin, an invaluable drug in the treatment of diabetes. With that, the era of biotechnology was born. A plethora of novel—or at least cheaper—drugs seemed to loom on the horizon.
Thirty-odd years on, molecular biologists have delivered on many parts of that early promise, engineering microbes to produce a wide range of pharmaceuticals, including experimental antimalarial medicines and antibiotics. A quick glance in the pantry or storage closet is likely to reveal other products of genetic engineering, too, including foods, food additives and colorings, and even laundry detergent. The list goes on and on.
The economic impact of all this has been enormous. Genetic engineering and other forms of biotechnology account for some 40 percent of the recent growth in the U.S. gross domestic product, for example. The biotech sectors in other countries have also made sizable contributions to their economies. And you can expect that trend to continue as genetically engineered organisms tackle even more diverse challenges, such as producing renewable fuels and cleaning up toxic waste.
Genetic engineers have indeed accomplished a great deal, but they've also run up against many obstacles in transforming microbial cells into factories that churn out useful substances. In a real-world factory, you need all your production machinery and employees operating in sync to run an efficient business. A cell also has components that act like machines, producing complex biological molecules, and other parts that act like messengers, ferrying around information in the form of chemical signals. Bioengineers have to do quite a bit of tricky fine-tuning to their cellular factories, manipulating the operation of many subcellular components so the cells don't die as they crank out the desired product in copious amounts.
