Xturing machine (Java Applet Example)
Leonard Adelman was the first person to actually do BioComputing. While at the University of Southern California, he used DNA to solve an instance of the Traveling Salesman problem.
He used DNA molecules to systematically encode connected cities and combined trillions of these in a test tube. He then took advantage of the pairing affinities to achieve an answer within a few minutes. The downside was that it took much longer at the time to retrieve the combinations representing success.
The following image shows how the enzyme FokI will act as a turing machine
and how the various components map to the Turing Machine model in the previous slide.
Although many seek to advantage of DNA's potential for computational power, some others have a more entertaining use of it. Paul W. K. Rothemund has found yet another use of DNA. He has started to build 2d images out of DNA that only take about 2 weeks from start to finish. Each of the images to the right is only a few hundred nanometers across.