Abstract

There are several issues in the switch from petroleum to alternative fuels. One problem is what to do with existing wastes such as leaking coal ash ponds. Another issue is the efficient production of an alcohol that is effective as a fuel, easy and inexpensive to produce, and will function within the current infrastructure. This year, we improved the sensitivity of our cadmium detector using sensitivity tuners. We are developing a strain of E. coli resistant to isobutanol and cloning GlmY, GlmZ, and IlvM which are genes involved in the isobutanol production pathway. Addition of sensitivity tuners has improved the cadmium detector approximately 4-fold, from 10mM to 2.5mM, still over the federal limit. The isobutanol resistant strain of E. coli can tolerate three times as much isobutanol as the original strain. Finally, we have successfully isolated the GlmZ coding region and have cloned it into the BioBrick vector.

The rising cost of petroleum, coupled with the environmental concerns that go with its use, have led to a recent increase in biofuel research. Developments in using bacteria to produce biofuels such as isobutanol and ethanol have come with this research. These alcohols are favored because they can easily be swapped into our current infrastructure of car and truck engines. At Gaston Day School, we have decided to launch a biofuel-focused project. To create the alcohols, we developed alcohol-resistant strains of E. Coli through artificial selection. Also, we are using PCR to amplify and ligate the genes GlmZ, GlmY, and IlmV, which are used in native alcohol production. The combination of these genes and the alcohol resistant strains are the first steps in our new biofuels project.

The surrounding areas of Duke Energy’s Buck Steam Station have unintentionally been affected with millions of tons of coal ash containing multiple toxic chemicals including cadmium. The release of this ash has caused the water to become a hazardous with the potential to cause a wide range of health issues: flu-like symptoms, kidney damage, fragile bones, and possibly death through prolonged exposure. To minimize the damage caused by cadmium in water both locally and globally, our 2012 team created several heavy metal detectors, but in 2013 we decided to concentrate on the cadmium detector. The detector responds to the presence of cadmium with green fluorescence. In 2014, the team worked to increase the sensitivity levels of our detector. Our detector needed to be able to respond to cadmium at low enough levels that the detection would be useful and the presence of cadmium would not already be apparent. This year, we completed the addition of the 2007 Cambridge team's sensitivity tuners to our detector. The sensitivity tuners amplify the signal received by the detector. At the end of last year, after adding the sensitivity tuners, we began to see indications of a peak at lower levels of cadmium than we had previously thought. To define that peak, we used test points that were closer together. We discovered a peak of fluorescence and identified our detection points.