Synthetic biology

Here's a strange new world, and one that was starting to emerge at the recent Design Automation Conference - synthetic biology. This is using biology to emulate what we do with current silicon technology.
Researchers are looking at ways to use bacteria and biological systems to provide electronic systems such as massively parallel image processor. This 'synthetic biology' had its own session at DAC for the first time this year and was reported in Electronics Weekly.
"We have reprogrammed the genomes of living cells to construct massively parallel biological computers capable of processing two-dimensional images at a theoretical resolution of greater than 100 megapixels per square inch," said Jeffrey Tabor,a researcher at the University of California at San Francisco. The researchers changed the genes in the bacteria to give out a pigment-producing enzyme under the control of red light. Shining an image onto a plate with the bacteria on it then acts as a photographic plate.
But they went a step further to use this as an edge detection system. Bacteria in dark areas were programmed to produce a membrane-diffusible molecule which stimulated the pigment. At the same time they also produced a repressor protein which made them immune go this, while the illuminated bacteria produced neither the repressor nor the pigment. If an illuminated bacterium was next to a dark area it received the inducer and produced the pigment. If an illuminated bacterium is alongside the dark area beyond some critical threshold for inducer, it produced no pigment.
"The result of this logic is that pigment is produced only at the boundary of light and dark and in this way, the community of independent cellular computers functions together to compute the edge of the image," said Tabor.