Jump to main content
Jump to site search

Issue 12, 2011
Previous Article Next Article

Live wires: direct extracellular electron exchange for bioenergy and the bioremediation of energy-related contamination

Author affiliations

Abstract

Microorganisms that can form direct electrical connections with insoluble minerals, electrodes, or other microorganisms can play an important role in some traditional as well as novel bioenergy strategies and can be helpful in the remediation of environmental contamination resulting from the use of more traditional energy sources. The surprising discovery that microorganisms in the genus Geobacter are capable of forming highly conductive networks of filaments that transfer electrons along their length with organic metallic-like conductivity, rather than traditional molecule to molecule electron exchange, provides an explanation for the ability of Geobacter species to grow in subsurface environments with insoluble Fe(III) oxides as the electron acceptor, and effectively remediate groundwater contaminated with hydrocarbon fuels or uranium and similar contaminants associated with the mining and processing of nuclear fuel. A similar organic metallic-like conductivity may be an important mechanism for microorganisms to exchange electrons in syntrophic associations, such as those responsible for the conversion of organic wastes to methane in anaerobic digesters, a proven bioenergy technology. Biofilms with conductivities rivaling those of synthetic polymers help Geobacter species generate the high current densities in microbial fuel cells producing electric current from organic compounds. Electron transfer in the reverse direction, i.e. from electrodes to microbes, is the basis for microbial electrosynthesis, in which microorganisms reduce carbon dioxide to fuels and other useful organic compounds with solar energy in a form of artificial photosynthesis that is more efficient and avoids many of the environmental sustainability concerns associated with biomass-based bioenergy strategies. The ability of Geobacter species to produce highly conductive electronic networks that function in water opens new possibilities in the emerging field of bioelectronics.

Graphical abstract: Live wires: direct extracellular electron exchange for bioenergy and the bioremediation of energy-related contamination

Back to tab navigation
Please wait while Download options loads

Publication details

The article was received on 27 Jul 2011, accepted on 07 Oct 2011 and first published on 28 Oct 2011


Article type: Perspective
DOI: 10.1039/C1EE02229F
Citation: Energy Environ. Sci., 2011,4, 4896-4906
  •   Request permissions

    Live wires: direct extracellular electron exchange for bioenergy and the bioremediation of energy-related contamination

    D. R. Lovley, Energy Environ. Sci., 2011, 4, 4896
    DOI: 10.1039/C1EE02229F

Search articles by author