Team:Wisconsin-Madison

From 2010.igem.org

The purpose of this project is to design an enzyme release system that only releases beta-galactosidase once it reaches the duodenum to potentially help a lactose intolerant patient metabolize lactose. The chassis for this system will be the common probiotic in yoghurt, Lactobacillus acidophilus. However, this system can be further modified to deliver other enzymes to the intestines or other parts of the body.

We hope to achieve increased survival of Lactobacillus acidophilus in the stomach and to produce a high amount of beta-galactosidase during the three to four hour digestion period. Once the Lactobacillus acidophilus has reached the duodenum, they will lyse by a timed inducible/repressible system, a bile-inducible system, or an encryption system.

Sequential logic switches are the basis for many common electronic devices such as digital clocks and calculators. Here we present a novel design for the imitation of sequential logic using basic genetic parts within E. Coli. By using a combination of DNA recombinase enzymes, promoter systems, and an innovative pattern of recombinase binding sites, we can reproduce sequential-logical functions on the compact molecular scale. By using single DNA molecules as a medium for such functions within bacterial vehicles, we can essentially mimic the functionality of a combination lock, and produce a "locked" gene which can be effectively "unlocked" only after a specific sequence of inputs detected by the bacterial promoter system. Since the DNA molecule is used as a logical medium, the "locked" and "unlocked" states are effectively heritable to subsequent bacterial cell lines, which would make such a system useful as the computational basis for many higher-order genetic devices from bacterial calculators to engineering of new metabolic pathways to bacterial drug delivery systems.