UCSF team develops ‘logic gates’ to program bacteria as computers

December 9, 2010

Screening process to obtain the functional sequential logic circuits (Nature)

A team of UCSF researchers has engineered E. coli bacteria with the key molecular circuitry that will enable genetic engineers to program cells to communicate and perform computations.

The work creates NOR gate logic circuits by “rewiring” communications between the bacteria. The gate controls the release and sensing of a chemical signal, which allows the gates to be connected among bacteria much the way electrical gates would be on a circuit boards. This system can be harnessed to turn cells into miniature computers, according to findings that will be reported in an upcoming issue of Nature and appear today in the advanced online edition at www.nature.com.

That, in turn, will enable cells to be programmed with more intricate functions for a variety of purposes, including agriculture and the production of pharmaceuticals, materials and industrial chemicals, according to Christopher A. Voigt, PhD, a synthetic biologist and associate professor in the UCSF School of Pharmacy’s Department of Pharmaceutical Chemistry who is senior author of the paper.

“We think of electronic currents as doing computation, but any substrate can act like a computer, including gears, pipes of water, and cells,” Voigt said. “Here, we’ve taken a colony of bacteria that are receiving two chemical signals from their neighbors, and have created the same logic gates that form the basis of silicon computing.”

“The purpose of programming cells is … to be able to access all of the things that biology can do in a reliable, programmable way,” said Voigt.

The research already has formed the basis of an industry partnership with Life Technologies, in Carlsbad, Cal., in which the genetic circuits and design algorithms developed at UCSF will be integrated into a professional software package as a tool for genetic engineers, much as computer-aided design is used in architecture and the development of advanced computer chips.

The automation of these complex operations and design choices will advance basic and applied research in synthetic biology. In the future, Voigt said the goal is to be able to program cells using a formal language that is similar to the programming languages currently used to write computer code.

Ref.: Synthesizing a novel genetic sequential logic circuit: a push-on push-off switch, Nature

Adapted from materials provided by UCSF