title: Unbalanced fermentation of glycerol in Escherichia coli via heterologous production of an electron transport chain and electrode interaction in microbial electrochemical cells.
abstract: Microbial electrochemical cells are an emerging technology for achieving unbalanced fermentations. However, organisms that can serve as potential biocatalysts for this application are limited by their narrow substrate spectrum. This study describes the reprogramming of Escherichia coli for the efficient use of anodes as electron acceptors. Electron transfer into the periplasm was accelerated by 183% via heterologous expression of the c-type cytochromes CymA, MtrA and STC from Shewanella oneidensis. STC was identified as a target for heterologous expression via a two-stage screening approach. First, mass spectroscopic analysis revealed natively expressed cytochromes in S. oneidensis. Thereafter, the corresponding genes were cloned and expressed in E. coli to quantify periplasmic electron transfer activity using methylene blue. This redox dye was further used to expand electron transfer to carbon electrode surfaces. The results demonstrate that E. coli can be reprogrammed from glycerol fermentation to respiration upon production of the new electron transport chain.
authors: Institute for Applied Biosciences, Department of Applied Biology, Karlsruhe Institute of Technology, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany.
authors: Katrin
authors: K
authors: Sturm-Richter
authors: Institute for Applied Biosciences, Department of Applied Biology, Karlsruhe Institute of Technology, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany.
authors: Frederik
authors: F
authors: Golitsch
authors: Institute for Applied Biosciences, Department of Applied Biology, Karlsruhe Institute of Technology, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany.
authors: Gunnar
authors: G
authors: Sturm
authors: Laboratory for MEMS Applications, IMTEK - Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee 103, D-79110 Freiburg, Germany.
authors: Elena
authors: E
authors: Kipf
authors: Institute of Photogrammetry and Remote Sensing, Englerstraße 7, D-76131 Karlsruhe, Germany.
authors: André
authors: A
authors: Dittrich
authors: Institute for Applied Biosciences, Department of Applied Biology, Karlsruhe Institute of Technology, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany.
authors: Sebastian
authors: S
authors: Beblawy
authors: Laboratory for MEMS Applications, IMTEK - Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee 103, D-79110 Freiburg, Germany.
authors: Sven
authors: S
authors: Kerzenmacher
authors: Institute for Applied Biosciences, Department of Applied Biology, Karlsruhe Institute of Technology, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany. Electronic address: johannes.gescher@kit.edu.
authors: Johannes
authors: J
authors: Gescher
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D019069:Cell Respiration / Q000502:physiology; D003574:Cytochrome c Group / Q000378:metabolism; D004566:Electrodes / Q000382:microbiology*; D004579:Electron Transport / Q000502:physiology*; D004926:Escherichia coli / Q000378:metabolism*; D005285:Fermentation / Q000502:physiology*; D005990:Glycerol / Q000378:metabolism*; D010084:Oxidation-Reduction; D019897:Periplasm / Q000378:metabolism; D020592:Shewanella / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D003574:Cytochrome c Group; D005990:Glycerol
keywords: E. coli; Microbial fuel cell; Shewanella oneidensis; Unbalanced fermentation; c-Type cytochrome