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Team:Austin Texas
From 2012.igem.org
Project Caffeinated coli
The widespread use of caffeine (1,3,7–trimethylxanthine) and other methylxanthines in beverages and pharmaceuticals has led to significant environmental pollution. Indeed, a leading method for the detection of human sewage contamination is caffeine content. We seek to develop a novel bioremediation strategy for caffeine contamination by engineering Escherichia coli to degrade caffeine to metabolites that can be utilized by the bacterium for energy and DNA synthesis. To achieve this, we will reconstruct the caffeine degradation operon from Pseudomonas putida CBB5, an organism capable of degrading methylxanthines by N-demethylation. The reconstructed operon will be evaluated for caffeine degredation functionality in e.coli. In addition to bioremediation, our engineered e.coli could potentially be used for decaffeination of caffeinated beverages or for the production of high value dimethyl and monomethyl xanthines.
Project ZombiE.coli
UT’s ZombiE.coli aims to a develop a tightly regulated genetic switch that is triggered by bacterial quorum signaling and leads to feed-forward propagation of the genetic output in the form of red or green fluorescence as well as amplification of quorum signaling. The switch relies on simple one-way Cre/loxP recombination combined with native quorum signaling to provide us with a system that models transmissible disease spread between populations. We have likened this to an airborne zombie epidemic, in which a an “infected” zombie cell is capable of restructuring the genes of a normal cell, turning it into a flesh-hungry counterpart. This system will be useful not only as a simple disease outbreak model for intermediate-level biology education, but also, could provide new insights to how bacterial populations communicate in three dimensions and under different genetic backgrounds.
Project Spinach-mCherry Dual Reporter
In an effort to improve both efficiency, ease, and quality of promoter and RBS strength meaurements, we focused on developing a dual fluorescence reporter for simultaneous monitoring both transcription and translation. To measure both processes separately, two fluorescent reporters, the Spinach aptamer and mCherry red fluorescent protein, were assembled into a single construct. The Spinach-mCherry dual reporter is a unique concept; Spinach is a short RNA aptamer that binds to its ligand, DFHBI, and allows it to emit green fluorescence similar to GFP. This gives insight into the direct production of the mCherry-encoding mRNA without the need to wait for protein folding and maturation of the fluorophore. This technique attempted to expand upon current efforts to measure promoter strength relative to a reference standard used by the iGEM community.
