Difference between revisions of "Team:TJU/Description"

This year, we successfully construct a three species co-culture MFC (microbial fuel cell) system. Through the electricity generation platform we design, the final electrical output of the system reaches more than 510 mV and lasts over 80 h. What’s more, the co-culture MFC system can not only enhance the electrical output significantly but also broaden the spectrum of carbon sources. This is the very first time to introduce three different species into MFC system, namely E. coli, Shewanella and B. subtilis. We strongly believe our MFC system will have wide prospects in future application.

Figure 1. The overall relationship of three kinds of bacteria in our co-culture system.

Microorganisms rarely live in isolated niches because natural microbial communities have unique advantages of stability, robustness and versatility due to nutrient adaptability, stress resistance, complicated interactions, etc. Considering that single-strain MFCs face many practical barriers such as narrow range of carbon sources, low efficiency of electricity generation, demanding requirements for environment and so on, we aim to construct new generation of MFC system by using synthetic consortia with elaborate labor division.

In our system, there are two kinds of fermentation bacteria and one electricigen. Co-culture strategy among zymophyte and electricigen develops a delicate commensalism relation on the basis of material, energy and information flow, which may remarkably benefit the whole system.

Material Flow

For the material flow, we construct an engineered E. coli strain to provide proper amount of carbon source, lactate, for Shewanella which have a poor ability of utilizing glucose. In this way, we broaden the spectrum of carbon sources of Shewanella to glucose and even xylose, cellose and cellulose in the future.

Energy & Information Flow

As for energy and information flow, we choose riboflavin as our entry point. It is because riboflavin is the major factor determining the extracellular electron transfer efficiency of electricigen. Firstly, we construct high-yield engineered E. coli