Comparison of anode bacterial communities and performance in microbial fuel cells with different electron donors
- 1.8k Downloads
Microbial fuel cells (MFCs) harness the electrochemical activity of certain microbes for the production of electricity from reduced compounds. Characterizations of MFC anode biofilms have collectively shown very diverse microbial communities, raising ecological questions about competition and community succession within these anode-reducing communities. Three sets of triplicate, two-chamber MFCs inoculated with anaerobic sludge and differing in energy sources (acetate, lactate, and glucose) were operated to explore these questions. Based on 16S rDNA-targeted denaturing gradient gel electrophoresis (DGGE), all anode communities contained sequences closely affiliated with Geobacter sulfurreducens (>99% similarity) and an uncultured bacterium clone in the Bacteroidetes class (99% similarity). Various other Geobacter-like sequences were also enriched in most of the anode biofilms. While the anode communities in replicate reactors for each substrate generally converged to a reproducible community, there were some variations in the relative distribution of these putative anode-reducing Geobacter-like strains. Firmicutes were found only in glucose-fed MFCs, presumably serving the roles of converting complex carbon into simple molecules and scavenging oxygen. The maximum current density in these systems was negatively correlated with internal resistance variations among replicate reactors and, likely, was only minimally affected by anode community differences in these two-chamber MFCs with high internal resistance.
KeywordsChemical Oxygen Demand Clone Library Microbial Fuel Cell Bacteroidetes Shewanella
This research was supported by a USDA Biomass Initiative Grant (68-3A75-3-150). The authors thank Jung Rae Kim and Ah-Young Cho for their valuable suggestions and David Jones for the GC analyses.
- Caccavo F Jr, Lonergan DJ, Lovley DR, Davis M, Stolz JF, McInerney MJ (1994) Geobacter sulfurreducens sp. nov., a hydrogen- and acetate-oxidizing dissimilatory metal-reducing microorganism. Appl Environ Microbiol 60(10):3752–3759Google Scholar
- Choo YF, Lee J, Chang IS, Kim H (2006) Bacterial communities in microbial fuel cells enriched with high concentrations of glucose and glutamate. J Microbiol Biotechnol 16(9):1481–1484Google Scholar
- Gorby YA, Yanina S, McLean JS, Rosso KM, Moyles D, Dohnalkova A, Beveridge TJ, Chang IS, Kim BH, Kim KS, Culley DE, Reed SB, Romine MF, Saffarini DA, Hill EA, Shi L, Elias DA, Kennedy DW, Pinchuk G, Watanabe K, Ishii S, Logan B, Nealson KH, Fredrickson JK (2006) Electrically conductive bacterial nanowires produced by Shewanella oneidensis strain MR-1 and other microorganisms. Proc Natl Acad Sci USA 103(30):11358–11363CrossRefGoogle Scholar
- Gottschalk G (1986) Bacterial metabolism. Springer, New YorkGoogle Scholar
- Kim GT, Hyun MS, Chang IS, Kim HJ, Park HS, Kim BH, Kim SD, Wimpenny JW, Weightman AJ (2005a) Dissimilatory Fe(III) reduction by an electrochemically active lactic acid bacterium phylogenetically related to Enterococcus gallinarum isolated from submerged soil. J Appl Microbiol 99(4):978–987CrossRefGoogle Scholar
- Lovley DR, Phillips EJP (1988) Novel mode of microbial energy metabolism: organic carbon oxidation coupled to dissimilatory reduction of iron or manganese. Appl Environ Microbiol 54(6):1472–1480Google Scholar
- Lovley DR, Giovannoni SJ, White DC, Champine JE, Phillips EJ, Gorby YA, Goodwin S (1993) Geobacter metallireducens gen. nov. sp. nov., a microorganism capable of coupling the complete oxidation of organic compounds to the reduction of iron and other metals. Arch Microbiol 159(4):336–344CrossRefGoogle Scholar
- Muyzer G, Brinkhoff T, Nubel U, Santegoeds C, Schafer H, Wawer C (2004) Denaturing gradient gel electrophoresis (DGGE) in microbial ecology. In: Akkermans ADL, van Elsas JD, de Bruijn F (eds) Molecular microbial ecology manual, 2nd edn. Kluwer, The Netherlands, pp 743–770Google Scholar
- Oh SE, Logan BE (2005) Proton exchange membrane and electrode surface areas as factors that affect power generation in microbial fuel cells. Appl Microbiol Biotechnol 70(2):1–8Google Scholar
- Tender LM, Reimers CE, Stecher HA, Holmes DE, Bond DR, Lowy DA, Pilobello K, Fertig SJ, Lovley DR (2002) Harnessing microbially generated power on the seafloor. Nat Biotechnol 20(8):821–825Google Scholar