David Kirkpatrick

October 30, 2008

A molecular clock

This is a cool story from Technology Review.

From the link:

A Fast, Programmable Molecular Clock

The bacteria-based timepiece could be used as a biosensor for changing environmental conditions.
Wednesday, October 29, 2008
By Emily Singer

UC San Diego bioengineers have created the first stable, fast, and programmable genetic clock that reliably keeps time by the blinking of fluorescent proteins inside E. coli cells. The clock’s blink rate changes when the temperature, energy source, or other environmental conditions change. Shown here is a microfluidic system capable of controlling the environmental conditions of the E. coli cells with great precision–one of the keys to this advance.
Credit: UC San Diego Jacobs School of Engineering

A molecular timepiece that ticks away the time with a flash of fluorescent protein could provide the basis for novel biosensors. The clock, or synthetic gene oscillator, is a feat of synthetic biology–a fledgling field in which researchers engineer novel biological “parts” into organisms.

To create the clock, scientists genetically engineered a molecular oscillator composed of multiple gene promoters, which turn genes on in the presence of certain chemicals, and genes themselves, one of which codes for a fluorescent protein. When expressed in E. coli bacteria, the feedback system turns the fluorescent gene on and off at regular intervals.