A new model for electron flow during anaerobic digestion: direct interspecies electron transfer to Methanosaeta for the reduction of carbon dioxide to methane

Energy & Environmental Science, Год журнала: 2013, Номер 7(1), С. 408 - 415

Опубликована: Окт. 18, 2013

Anaerobic conversion of organic wastes and biomass to methane is an important bioenergy strategy, which depends on poorly understood mechanisms interspecies electron transfer methanogenic microorganisms. Metatranscriptomic analysis aggregates from a brewery wastewater digester, coupled with fluorescence in situ hybridization specific 16S rRNA probes, revealed that Methanosaeta species were the most abundant metabolically active methanogens. Methanogens known reduce carbon dioxide H2 or formate as donor rare. Although have previously been thought be restricted acetate substrate for production, had complete complement genes enzymes necessary reduction methane, transcript abundance these was high. Furthermore, Geobacter species, bacteria aggregates, highly expressed ethanol metabolism extracellular via electrically conductive pili, suggesting exchanging electrons direct (DIET). This possibility further investigated defined co-cultures metallireducens harundinacea stoichiometrically converted methane. Transcriptomic, radiotracer, genetic demonstrated M. accepted DIET The discovery are wide diversity environments, capable has implications not only functioning anaerobic digesters, but also global production.

Язык: Английский

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Direct Interspecies Electron Transfer between Geobacter metallireducens and Methanosarcina barkeri

Applied and Environmental Microbiology, Год журнала: 2014, Номер 80(15), С. 4599 - 4605

Опубликована: Май 17, 2014

ABSTRACT Direct interspecies electron transfer (DIET) is potentially an effective form of syntrophy in methanogenic communities, but little known about the diversity methanogens capable DIET. The ability Methanosarcina barkeri to participate DIET was evaluated coculture with Geobacter metallireducens . Cocultures formed aggregates that shared electrons via during stoichiometric conversion ethanol methane. could not be initiated a pilin-deficient G. strain, suggesting long-range along pili important for Amendments granular activated carbon permitted isolates share M. , demonstrating this conductive material substitute promoting When grown H 2 -producing Pelobacter carbinolicus incapable DIET, utilized as donor metabolized acetate P. produced. This suggested derived from inhibited metabolism. carbinolicus-M. cocultures did aggregate, that, unlike close physical contact necessary transfer. second methanogen found accept and first using either or CO reduction. Furthermore, genetically tractable, making it model organism elucidating mechanisms by which make biological electrical connections other cells.

Язык: Английский

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The interplay of microbially mediated and abiotic reactions in the biogeochemical Fe cycle

Nature Reviews Microbiology, Год журнала: 2014, Номер 12(12), С. 797 - 808

Опубликована: Окт. 20, 2014

Язык: Английский

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Electromicrobiology

Annual Review of Microbiology, Год журнала: 2012, Номер 66(1), С. 391 - 409

Опубликована: Июль 2, 2012

Electromicrobiology deals with the interactions between microorganisms and electronic devices novel electrical properties of microorganisms. A diversity can donate electrons to, or accept from, electrodes without addition artificial electron shuttles. However, mechanisms for microbe-electrode exchange have been seriously studied in only a few Shewanella oneidensis interacts primarily via flavins that function as soluble Geobacter sulfurreducens makes direct contacts outer-surface, c-type cytochromes. G. is also capable long-range transport along pili, known microbial nanowires, metallic-like conductivity similar to previously described synthetic conducting polymers. Pili networks confer biofilms, which polymer, supercapacitor transistor functionalities. Conductive and/or their nanowires number potential practical applications, but additional basic research will be necessary rational optimization.

Язык: Английский

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Pseudomonas aeruginosa Twitching Motility: Type IV Pili in Action

Annual Review of Microbiology, Год журнала: 2012, Номер 66(1), С. 493 - 520

Опубликована: Июль 2, 2012

Type IV pili (T4P) are one of the most common forms bacterial and archaeal surface structures, involved in adherence, motility, competence for DNA uptake, pathogenesis. Pseudomonas aeruginosa has emerged as key model systems investigation T4P structure function. Although its reputation a serious nosocomial opportunistic pathogen is well deserved, facile growth requirements ready availability molecular tools have allowed rapid advances our understanding how assembled; their contributions to biofilm formation virulence; complex regulation. This review covers recent findings concerning three different types found P. (type IVa, type IVb, Tad) provides details about modes translocation mediated by T4aP, architecture function T4aP assembly system, regulation biogenesis

Язык: Английский

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Accelerated cathodic reaction in microbial corrosion of iron due to direct electron uptake by sulfate-reducing bacteria

Corrosion Science, Год журнала: 2012, Номер 66, С. 88 - 96

Опубликована: Сен. 19, 2012

Microbially influenced iron corrosion by sulfate-reducing bacteria (SRB) is conventionally attributed to the chemical corrosiveness of H2S, facilitated abiotic H+-reduction at deposited FeS, and biological consumption chemically formed (‘cathodic’) H2. However, recent studies with corrosive SRB indicated direct iron-derived electrons rather than H2 as a crucial mechanism. Here, we conducted potentiodynamic measurements electrodes colonized SRB. They significantly stimulated cathodic reaction, while non-corrosive yet H2-consuming control had no effect. Inactivation colonizing reduced current stimulation, thus confirming catalysis an effect FeS.

Язык: Английский

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Type IV Pilin Proteins: Versatile Molecular Modules

Microbiology and Molecular Biology Reviews, Год журнала: 2012, Номер 76(4), С. 740 - 772

Опубликована: Ноя. 29, 2012

SUMMARY Type IV pili (T4P) are multifunctional protein fibers produced on the surfaces of a wide variety bacteria and archaea. The major subunit T4P is type pilin, structurally related proteins found as components II secretion (T2S) system, where they called pseudopilins; DNA uptake/competence systems in both Gram-negative Gram-positive species; flagella, pili, sugar-binding This broad distribution single family implies common evolutionary origin highly adaptable functional plan. pilin remarkably versatile architectural module that has been adopted widely for functions, including motility, attachment to chemically diverse surfaces, electrical conductance, acquisition DNA, range distinct substrates. In this review, we consider recent advances research area, from structural revelations insights into diversity, posttranslational modifications, regulation, function.

Язык: Английский

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Flavin Electron Shuttles Dominate Extracellular Electron Transfer by Shewanella oneidensis

mBio, Год журнала: 2013, Номер 4(1)

Опубликована: Янв. 16, 2013

Shewanella oneidensis strain MR-1 is widely studied for its ability to respire a diverse array of soluble and insoluble electron acceptors. The breathe substrates defined as extracellular transfer can occur via direct contact or by shuttling in S. oneidensis. To determine the contribution flavin shuttles transfer, transposon mutagenesis screen was performed with identify mutants unable secrete flavins. A multidrug toxin efflux transporter encoded SO_0702 identified renamed bfe (bacterial adenine dinucleotide [FAD] exporter) based on phenotypic characterization. Deletion resulted severe decrease flavins, while overexpression increased concentration Strains lacking had no defect reduction Fe(III), but these strains were deficient rate Fe(III) oxide reduction, which alleviated addition exogenous test different acceptor, graphite electrode bioreactors set up measure current produced wild-type Δbfe mutant. With same supplemented two similar amounts current. However, when flavins not bioreactors, mutant significantly less than wild type. We have demonstrated that accounts ~75% first FAD bacteria.Extracellular microbes critical geochemical cycling metals, bioremediation, biocatalysis using electrodes. controversy field addressed demonstrating shuttling, nanowires, primary mechanism employed bacterium conserved all sequenced species facilitates export Analysis capacity

Язык: Английский

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Electromicrobiology: the ecophysiology of phylogenetically diverse electroactive microorganisms

Nature Reviews Microbiology, Год журнала: 2021, Номер 20(1), С. 5 - 19

Опубликована: Июль 27, 2021

Язык: Английский

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Direct interspecies electron transfer via conductive materials: A perspective for anaerobic digestion applications

Bioresource Technology, Год журнала: 2018, Номер 254, С. 300 - 311

Опубликована: Фев. 2, 2018

Язык: Английский

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