Project Overview
Welcome to
Yale-iGEM 2010!
In our inaugural year of iGEM competition, we have designed a system to harness biology to construct conductive circuits.
By enabling E. coli to affect local redox chemistry, we can use bacteria to catalyze metal deposition. When this activity is controlled spatially and temporally, this method could be used to construct circuit elements in a specified geometry. This would allow the manufacture of electrical components under biological conditions.
What would it take to...
Build a circuit using microbially catalyzed metal deposition?
In an effort to achieve our goal, we have designed a bacterial model using synthetic biology. A gene encoding the protein Thisulfate Reductase has been inserted Our initial research indicated that several observations have been made of natural mechanisms for metal deposition and precipitation in a family of microorganisms called Sulfate Reducing Bacteria (SRB). These SRB comrpise a class of chemolithotrophic microbes that couple anaerobic electron transport to ATP synthesis using sulfate as the terminal electron acceptor. Importantly, as a consequence of their metabolism, SRB produce hydrogen sulfide: a gas that can be used to reduce metals in solution.
These H2S Producing bacteria were found to form significant concentrations of solid metals on and around their cell surface. The H2S gas reduces free metal ions in solution to form a metal sulfide, which subsequently precipitates out of solution. The metal sulfide can self-associate to form clusters of
had the capability to reduce could be used to catalyze the precipitation of metal solids in solutions containing metal in the appropriate ionic state.
Biochemistry of Sulfate Reducing Bacteria
Papers on Sulfate Reducing Bacteria
Sulfate Reducing Bacteria (SRB) comprise a class of chemolithotrophic microorganisms that couple anaerobic electron transport to ATP synthesis, using sulfate as a terminal electron acceptor.