Off Switches for Killer Bacteria

Genetically engineered (GE) bacteria are not just the stuff of science fiction novels. They can be used to carry biomarkers and treatments to cancer tumors as well as to control and eliminate oil spills.

But how do we get rid of these helpers once their task is complete? 

Off switches.

Clement T Y Chan, Jeong Wook Lee, D Ewen Cameron, Caleb J Bashor & James J Collins, (researchers at MIT's Institute for Medical Engineering & Science, Cambridge, Massachusetts) have created synthetic gene circuits that act as "OFF Switches" that kill GE microbes once their job is done. Two circuits, described in the Dec. 7th issue of Nature Chemical Biology, increase the safety of diagnostics, therapies, or environmental remediation strategies based upon GE bacteria. They are called appropriately called "Deadman" and "Passcode." Its good to know folks are thinking ahead. Go science!