A novel electrochemically active and Fe(III)-reducing bacterium phylogenetically related to Clostridium butyricum isolated from a microbial fuel cell

An obligatory anaerobic bacterium was isolated from a mediator-less microbial fuel cell using starch processing wastewater as the fuel and designated as EG3. The isolate was Gram-positive, motile and rod (2.8–3.0 μm long, 0.5–0.6 μm wide). The partial 16S rRNA gene sequence and analysis of the cellular fatty acids profile suggested that EG3 clusters with Clostridium sub-phylum and exhibited the highest similarity (98%) with Clostridium butyricum. The temperature and pH optimum for growth were 37°C and 7.0, respectively. The major products of glucose and glucose/Fe(O)OH metabolism were lactate, formate, butyrate, acetate, CO2and H2. Growth was faster at the initial phase and the cell yield was higher when the medium was supplemented with Fe(O)OH than without Fe(O)OH. These results suggest that Fe(III) ion is utilised as an electron sink. Cyclic voltammetry showed that Clostridium butyricum EG3 cells were electrochemically active. It is a novel characteristic of strict anaerobic Gram-positive bacteria.

[1]  M. Pallen,et al.  An embarrassment of sortases - a richness of substrates? , 2001, Trends in microbiology.

[2]  Byung Hong Kim,et al.  Isolation and Identification of an Anaerobic Dissimilatiory Fe(III)-Reducing Bacterium, Shewanella Puterefaciens IR-1 , 1999 .

[3]  P. Dobbin,et al.  Dissimilatory Fe(III) reduction by Clostridium beijerinckii isolated from freshwater sediment using Fe(III) maltol enrichment. , 1999, FEMS microbiology letters.

[4]  Byung Hong Kim,et al.  Direct electrode reaction of Fe(III)-reducing bacterium, Shewanella putrefaciens , 1999 .

[5]  Anna Obraztsova,et al.  Sulfate-reducing bacterium grows with Cr(VI), U(VI), Mn(IV), and Fe(III) as electron acceptors , 1998 .

[6]  Byung Hong Kim,et al.  CO Fermentation of Eubacterium limosum KIST612 , 1998 .

[7]  Thomas L. Madden,et al.  Gapped BLAST and PSI-BLAST: a new generation of protein database search programs. , 1997, Nucleic acids research.

[8]  B. Patel,et al.  Deferribacter thermophilus gen. nov., sp. nov., a novel thermophilic manganese- and iron-reducing bacterium isolated from a petroleum reservoir. , 1997, International journal of systematic bacteriology.

[9]  Byung Hong Kim,et al.  Electrode reaction of Desulfovibrio desulfuricans modified with organic conductive compounds , 1997 .

[10]  D. Bezdicek,et al.  Estimation of the abundance of an uncultured soil bacterial strain by a competitive quantitative PCR method , 1996, Applied and environmental microbiology.

[11]  H. Hill,et al.  Direct electrochemistry of the hydroxylase of soluble methane monooxygenase from Methylococcus capsulatus (Bath). , 1996, European journal of biochemistry.

[12]  E. Stackebrandt,et al.  Clostridium paradoxum DSM 7308T contains multiple 16S rRNA genes with heterogeneous intervening sequences. , 1996, Microbiology.

[13]  K. Schleifer,et al.  Geovibrio ferrireducens, a phylogenetically distinct dissimilatory Fe(III)-reducing bacterium , 1996, Archives of Microbiology.

[14]  D. Lovley,et al.  Isolation of Geobacter species from diverse sedimentary environments , 1996, Applied and environmental microbiology.

[15]  N. Cook,et al.  Dissimilatory iron(III) reduction by Rhodobacter capsulatus. , 1996, Microbiology.

[16]  Byung Hong Kim,et al.  Bacterial Contamination and Its Effects on Ethanol Fermentation , 1995 .

[17]  P. Gerhardt,et al.  Methods for general and molecular bacteriology , 1994 .

[18]  C. Myers,et al.  Localization of cytochromes to the outer membrane of anaerobically grown Shewanella putrefaciens MR-1 , 1992, Journal of bacteriology.

[19]  D. Lovley,et al.  Hydrogen and Formate Oxidation Coupled to Dissimilatory Reduction of Iron or Manganese by Alteromonas putrefaciens , 1989, Applied and environmental microbiology.

[20]  Lovley DerekR..  Organic matter mineralization with the reduction of ferric iron: A review , 1987 .

[21]  D. Lovley,et al.  Organic Matter Mineralization with Reduction of Ferric Iron in Anaerobic Sediments , 1986, Applied and environmental microbiology.

[22]  P. Sneath.  Endospore-forming gram-positive rods and cocci, , 1986 .

[23]  J. Buck,et al.  Nonstaining (KOH) method for determination of gram reactions of marine bacteria , 1982, Applied and environmental microbiology.

[24]  J. Syers,et al.  SORPTION OF INORGANIC PHOSPHATE BY IRON‐ AND ALUMINIUM‐ CONTAINING COMPONENTS , 1981 .

[25]  R. E. Hungate,et al.  The Roll-Tube Method for Cultivation of Strict Anaerobes , 1972 .

[26]  L. D. Metcalfe,et al.  Rapid Preparation of Fatty Acid Esters from Lipids for Gas Chromatographic Analysis. , 1966 .