Team:LZU-China

            Microbial Fuel Cells (MFCs) which can convert contaminants in wastewaters into energy is an ideal approach to solve both pollution problem and energy crisis. However, MFCs still have disadvantages such as hard to determine the contaminants concentrations which is a major drawback for MFCs applications.

            In our study, we found that the electricity produced by MFCs was weakly correlated to the substrates' concentrations such as P-nitrophenol (PNP) in anode or Chromium (VI) in cathode. But the electricity produced was not stable and so did the correlations. Therefore, we hypothesize that a) by using genetic engineered bacteria, the MFC's electricity will be more stable and correlated with substrates concentrations. b) By monitoring MFC's electricity, it will be possible to measure substrates' concentrations.

            In this study, we've designed a novel MFC system. For anode strain, we've cloned a NO3- sensor sequence and a riboflavin producing genes into Escherichia coli. The recombinants is able to detect PNP and produce riboflavin to boost electrical generation when co-cultured with Shewanella oneidensis. In the cathode, gene codes chromate (VI) reductase Yief was cloned into E.coli. The stability of MFCs has been improved and the electricity generated was correlated with the substrates. Moreover, based on this correlation, we've designed a cell phone program which is able to remotely monitor the contaminants concentrations in MFCs.