@article {3048,
	title = {Microbial biofilms for electricity generation from water evaporation and power to wearables.},
	journal = {Nat Commun},
	volume = {13},
	year = {2022},
	month = {2022 Jul 28},
	pages = {4369},
	abstract = {<p>Employing renewable materials for fabricating clean energy harvesting devices can further improve sustainability. Microorganisms can be mass produced with renewable feedstocks. Here, we demonstrate that it is possible to engineer microbial biofilms as a cohesive, flexible material for long-term continuous electricity production from evaporating water. Single biofilm sheet (~40 {\textmu}m thick) serving as the functional component in an electronic device continuously produces power density (~1 μW/cm) higher than that achieved with thicker engineered materials. The energy output is comparable to that achieved with similar sized biofilms catalyzing current production in microbial fuel cells, without the need for an organic feedstock or maintaining cell viability. The biofilm can be sandwiched between a pair of mesh electrodes for scalable device integration and current production. The devices maintain the energy production in ionic solutions and can be used as skin-patch devices to harvest electricity from sweat and moisture on skin to continuously power wearable devices. Biofilms made from different microbial species show generic current production from water evaporation. These results suggest that we can harness the ubiquity of biofilms in nature as additional sources of biomaterial for evaporation-based electricity generation in diverse aqueous environments.</p>},
	keywords = {Bioelectric Energy Sources, Biofilms, Electricity, Electrodes, Water, Wearable Electronic Devices},
	issn = {2041-1723},
	doi = {10.1038/s41467-022-32105-6},
	author = {Liu, Xiaomeng and Ueki, Toshiyuki and Gao, Hongyan and Woodard, Trevor L and Nevin, Kelly P and Fu, Tianda and Fu, Shuai and Sun, Lu and Lovley, Derek R and Yao, Jun}
}
@article {3092,
	title = {Metatranscriptomic Evidence for Direct Interspecies Electron Transfer between Geobacter and Methanothrix Species in Methanogenic Rice Paddy Soils.},
	journal = {Appl Environ Microbiol},
	volume = {83},
	year = {2017},
	month = {2017 May 01},
	abstract = {<p>The possibility that  (formerly ) and  species cooperate via direct interspecies electron transfer (DIET) in terrestrial methanogenic environments was investigated in rice paddy soils. Genes with high sequence similarity to the gene for the PilA pilin monomer of the electrically conductive pili (e-pili) of  accounted for over half of the PilA gene sequences in metagenomic libraries and 42\% of the mRNA transcripts in RNA sequencing (RNA-seq) libraries. This abundance of e-pilin genes and transcripts is significant because e-pili can serve as conduits for DIET. Most of the e-pilin genes and transcripts were affiliated with  species, but sequences most closely related to putative e-pilin genes from genera such as , , , and , were also detected. Approximately 17\% of all metagenomic and metatranscriptomic bacterial sequences clustered with  species, and the finding that  spp. were actively transcribing growth-related genes indicated that they were metabolically active in the soils. Genes coding for e-pilin were among the most highly transcribed  genes. In addition, homologs of genes encoding OmcS, a -type cytochrome associated with the e-pili of  and required for DIET, were also highly expressed in the soils.  species in the soils highly expressed genes for enzymes involved in the reduction of carbon dioxide to methane. DIET is the only electron donor known to support CO reduction in  Thus, these results are consistent with a model in which  species were providing electrons to  species for methane production through electrical connections of e-pili. species are some of the most important microbial contributors to global methane production, but surprisingly little is known about their physiology and ecology. The possibility that DIET is a source of electrons for  in methanogenic rice paddy soils is important because it demonstrates that the contribution that  makes to methane production in terrestrial environments may extend beyond the conversion of acetate to methane. Furthermore, defined coculture studies have suggested that when  species receive some of their energy from DIET, they grow faster than when acetate is their sole energy source. Thus,  growth and metabolism in methanogenic soils may be faster and more robust than generally considered. The results also suggest that the reason that  species are repeatedly found to be among the most metabolically active microorganisms in methanogenic soils is that they grow syntrophically in cooperation with  spp., and possibly other methanogens, via DIET.</p>},
	keywords = {Carbon Dioxide, Electron Transport, Fimbriae Proteins, Gene Expression Profiling, Geobacter, Metagenome, Methane, Methanosarcinaceae, Oryza, Soil Microbiology},
	issn = {1098-5336},
	doi = {10.1128/AEM.00223-17},
	author = {Holmes, Dawn E and Shrestha, Pravin M and Walker, David J F and Dang, Yan and Nevin, Kelly P and Woodard, Trevor L and Lovley, Derek R}
}
@article {435,
	title = {Microbial electrosynthesis: feeding microbes electricity to convert carbon dioxide and water to multicarbon extracellular organic compounds.},
	journal = {MBio},
	volume = {1},
	year = {2010},
	month = {2010},
	abstract = {The possibility of providing the acetogenic microorganism Sporomusa ovata with electrons delivered directly to the cells with a graphite electrode for the reduction of carbon dioxide to organic compounds was investigated. Biofilms of S. ovata growing on graphite cathode surfaces consumed electrons with the reduction of carbon dioxide to acetate and small amounts of 2-oxobutyrate. Electrons appearing in these products accounted for over 85\% of the electrons consumed. These results demonstrate that microbial production of multicarbon organic compounds from carbon dioxide and water with electricity as the energy source is feasible.},
	keywords = {Bioelectric Energy Sources, Carbon Dioxide, Electricity, Organic Chemicals, Veillonellaceae, Water},
	issn = {2150-7511},
	doi = {10.1128/mBio.00103-10},
	author = {Nevin, Kelly P and Woodard, Trevor L and Franks, Ashley E and Summers, Zarath M and Lovley, Derek R}
}
@article {451,
	title = {Molecular analysis of phosphate limitation in Geobacteraceae during the bioremediation of a uranium-contaminated aquifer.},
	journal = {ISME J},
	volume = {4},
	year = {2010},
	month = {2010 Feb},
	pages = {253-66},
	abstract = {Nutrient limitation is an environmental stress that may reduce the effectiveness of bioremediation strategies, especially when the contaminants are organic compounds or when organic compounds are added to promote microbial activities such as metal reduction. Genes indicative of phosphate-limitation were identified by microarray analysis of chemostat cultures of Geobacter sulfureducens. This analysis revealed that genes in the pst-pho operon, which is associated with a high-affinity phosphate uptake system in other microorganisms, had significantly higher transcript abundance under phosphate-limiting conditions, with the genes pstB and phoU upregulated the most. Quantitative PCR analysis of pstB and phoU transcript levels in G. sulfurreducens grown in chemostats demonstrated that the expression of these genes increased when phosphate was removed from the culture medium. Transcripts of pstB and phoU within the subsurface Geobacter species predominating during an in situ uranium-bioremediation field experiment were more abundant than in chemostat cultures of G. sulfurreducens that were not limited for phosphate. Addition of phosphate to incubations of subsurface sediments did not stimulate dissimilatory metal reduction. The added phosphate was rapidly adsorbed onto the sediments. The results demonstrate that Geobacter species can effectively reduce U(VI) even when experiencing suboptimal phosphate concentrations and that increasing phosphate availability with phosphate additions is difficult to achieve because of the high reactivity of this compound. This transcript-based approach developed for diagnosing phosphate limitation should be applicable to assessing the potential need for additional phosphate in other bioremediation processes.},
	keywords = {Biodegradation, Environmental, Fresh Water, Gene Expression Regulation, Bacterial, Geobacter, Phosphates, Uranium, Water Pollutants},
	issn = {1751-7370},
	doi = {10.1038/ismej.2009.115},
	author = {N{\textquoteright}guessan, Lucie A and Elifantz, Hila and Nevin, Kelly P and Mouser, Paula J and Meth{\'e}, Barbara and Woodard, Trevor L and Manley, Kimberly and Williams, Kenneth H and Wilkins, Michael J and Larsen, Joern T and Long, Philip E and Lovley, Derek R}
}
@article {513,
	title = {Microarray and genetic analysis of electron transfer to electrodes in Geobacter sulfurreducens.},
	journal = {Environ Microbiol},
	volume = {8},
	year = {2006},
	month = {2006 Oct},
	pages = {1805-15},
	abstract = {Whole-genome analysis of gene expression in Geobacter sulfurreducens revealed 474 genes with transcript levels that were significantly different during growth with an electrode as the sole electron acceptor versus growth on Fe(III) citrate. The greatest response was a more than 19-fold increase in transcript levels for omcS, which encodes an outer-membrane cytochrome previously shown to be required for Fe(III) oxide reduction. Quantitative reverse transcription polymerase chain reaction and Northern analyses confirmed the higher levels of omcS transcripts, which increased as power production increased. Deletion of omcS inhibited current production that was restored when omcS was expressed in trans. Transcript expression and genetic analysis suggested that OmcE, another outer-membrane cytochrome, is also involved in electron transfer to electrodes. Surprisingly, genes for other proteins known to be important in Fe(III) reduction such as the outer-membrane c-type cytochrome, OmcB, and the electrically conductive pilin "nanowires" did not have higher transcript levels on electrodes, and deletion of the relevant genes did not inhibit power production. Changes in the transcriptome suggested that cells growing on electrodes were subjected to less oxidative stress than cells growing on Fe(III) citrate and that a number of genes annotated as encoding metal efflux proteins or proteins of unknown function may be important for growth on electrodes. These results demonstrate for the first time that it is possible to evaluate gene expression, and hence the metabolic state, of microorganisms growing on electrodes on a genome-wide basis and suggest that OmcS, and to a lesser extent OmcE, are important in electron transfer to electrodes. This has important implications for the design of electrode materials and the genetic engineering of microorganisms to improve the function of microbial fuel cells.},
	keywords = {Bacterial Outer Membrane Proteins, Blotting, Northern, Cytochromes c, Electrodes, Electrophysiology, Gene Expression Regulation, Bacterial, Geobacter, Oligonucleotide Array Sequence Analysis, Oxidation-Reduction, Reverse Transcriptase Polymerase Chain Reaction, RNA, Bacterial, RNA, Messenger},
	issn = {1462-2912},
	doi = {10.1111/j.1462-2920.2006.01065.x},
	author = {Holmes, Dawn E and Chaudhuri, Swades K and Nevin, Kelly P and Mehta, Teena and Meth{\'e}, Barbara A and Liu, Anna and Ward, Joy E and Woodard, Trevor L and Webster, Jennifer and Lovley, Derek R}
}
