Some acetogenic bacteria are capable of using solid electron donors, such as a cathode or metallic iron [Fe(0)]. Acetogens donor interest for novel applications microbial electrosynthesis, while microorganisms Fe(0) cause detrimental induced corrosion. The capacity to use donors strongly differs between strains, which likely relates their extracellular transfer (EET) mechanism. Different EET mechanisms have been proposed bacteria, including direct mechanism and H2 dependent indirect combined...

The acetogen Clostridium ljungdahlii is capable of syngas fermentation and microbial electrosynthesis. Biofilm formation could benefit both these applications, but was not yet reported for C. ljungdahlii. does occur under standard growth conditions, attachment or aggregation be induced by different stresses. strongest biofilm observed with the addition sodium chloride. After 3 days incubation, biomass volume attached to a plastic surface 20 times higher than without 200 mM NaCl medium. also...

The involvement of Shewanella spp. in biocorrosion is often attributed to their Fe(III)-reducing properties, but they could also affect corrosion by using metallic iron as an electron donor. Previously, we isolated strain 4t3-1-2LB from acetogenic community enriched with Fe(0) the sole Here, investigated its use donor fumarate acceptor and explored corrosion-enhancing mechanism. Without Fe(0), fermented succinate CO2, was shown reaction stoichiometry pH. With completely reduced increased...

Abstract Acetogens share the capacity to convert H 2 and CO into acetate for energy conservation (ATP synthesis). This reaction is attractive applications, such as gas fermentation microbial electrosynthesis. Different partial pressures prevail in these distinctive applications (low concentrations during electrosynthesis [<40 Pa] vs. high with [>9%]). Strain selection thus requires understanding of how different acetogens perform under pressures. Here, we determined threshold (H...

Abstract The mechanism of electron transport across electroactive biofilms (EABs) is high interest and still a matter debate. Quantitative assessments their redox conduction take considerable time require non‐turnover conditions (absence substrate), which can be detrimental to EABs. Here, we measure the charge‐transport parameters Geobacter spp. dominated EABs with double potential step chronoamperometry (DPSC) Cottrell analysis. DPSC measurement simpler much faster than usual techniques...

Sporomusa sphaeroides related strains are to date the only homoacetogens known increase metallic iron corrosion. The goal of this work was isolate additional homoacetogenic bacteria capable using Fe(0) as electron donor and explore their extracellular transfer mechanism. Enrichments were started from anoxic corrosion products yielded Acetobacterium main genus. Isolations performed with a new procedure plates powder top layer. An strain, closely A. malicum wieringae, isolated, in addition S....

Measuring the distribution and dynamics of H 2 in microbial electrochemical reactors is valuable to gain insights into processes behind novel bioelectrochemical technologies, such as electrosynthesis. Here, a microsensor method measure profile dissolved concentrations standard H-cell described. Graphite cathodes were oriented horizontally enable use motorized microprofiling system stereomicroscope was used place precisely on cathode surface. Profiling performed towards gas-liquid interface,...

The toxicity of trichloroethene (TCE) likely restricts microbial activity in close vicinity a TCE dense nonaqueous phase liquid (DNAPL). This study examined the distribution dechlorinating community relation to distance from DNAPL using diffusion-cell set-up. Subcultures KB-1(™) culture cis-dichloroethene and grown with either formate or lactate as electron donor were used inoculate diffusion-cells. 16S rRNA gene clone library analysis showed that both inocula consisted bacteria similar...

Electromethanogenesis has emerged as a biological branch of Power-to-X technologies that implements methanogenic microorganisms, an alternative to chemical Power-to-X, convert electrical power from renewable sources, and CO2 into methane. Unlike biomethanation processes where is converted via exogenously added hydrogen, electromethanogenesis occurs in bioelectrochemical set-up combines electrodes microorganisms. Thereby, mixed, or pure cultures catalyze the reduction methane reducing...

Abstract Shewanella species are frequently selected as model strains to investigate microbially influenced steel corrosion. This selection is due their relevance for corrosion, but also because of easy cultivation in aerobic media. Unfortunately, these advantages do not lead a straight-forward interpretation corrosion inducing or inhibiting mechanisms. The metabolic versatility Shewanellae indeed enables wide variety work reviews the capacities and extracellular electron transfer mechanisms...

Microbial dechlorination of trichloroethene (TCE) is inhibited at elevated TCE concentrations. A batch experiment and modeling analysis were performed to examine whether this self-inhibition related an enhanced cell decay or a reduced activity increasing The combined four different initial concentrations (1.4–3.0 mM) three inoculation densities (4.0 × 105 4.0 107Geobacter cells·mL–1). Chlorinated ethene Geobacter 16S rRNA gene copy numbers measured. time required for complete conversion...

Abstract Acetogenic bacteria play an important role in various biotechnological processes, because of their chemolithoautotrophic metabolism converting carbon dioxide with molecular hydrogen (H 2 ) as electron donor into acetate. As the main factor limiting acetogenesis is often H , insights consumption kinetics acetogens required to assess potential processes. In this study, initial rates at a range different concentrations were measured for three acetogens. Interestingly, all strains, was...

ABSTRACT Acetogenic bacteria play an important role in various biotechnological processes, because of their chemolithoautotrophic metabolism converting carbon dioxide with molecular hydrogen (H 2 ) as electron donor into acetate. As the main factor limiting acetogenesis is often H , insights consumption kinetics acetogens are required to assess potential processes. In this study, initial rates at a range different concentrations were measured for three acetogens. Interestingly, all strains,...

The attention of even the most dedicated IP enthusiasts recently appears to have been distracted from pursuit just allocation profits and responsibilities attaching intellectual assets an issue that dwarfs all others: preservation planet. Daily we receive increasingly strident message our physical survival depends on paying immediate ecosystem, providing for every need. Global warming, chemical pollution, consumption irreplaceable assets, buildup greenhouse gases—these other topics travelled...