18-07: Escherichia coli as a platform for bioelectrosynthesis applications

One of the main challenges in the biofuels and biochemicals industry is the efficient conversion of fermentable sugar to product.  As a consequence, efforts to increase product yield are seen as vital to the commercialization of these processes.  Bioelectrosynthesis, the ability for microbes to directly use an electrode as a source of electrons to incorporate into their metabolism, has previously been suggested for use in the conversion of carbon dioxide to industrially important chemicals.  We have previously used in silico analyses to demonstrate that bioelectrosynthesis may be applied to improve yields for product synthesis.  Escherichia coli is a common organism in industry, however it is not useful in bioelectrosynthesis applications because it requires the use of expensive electron mediators.  Hence, we describe efforts to engineer E. coli to improve extracellular electron transfer without mediators.  We evaluate these results in the context of driving the synthesis of ethanol and other important  biochemicals, and compare these techniques against mediator driven bioelectrosynthesis.