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Showing 1 to 20 of 113 for “"methanogenesis"”.
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Analysis of Methylotrophic Methanogenesis in Methanosarcina Barkeri Fusaro
… of substrates to methane gas. Methylotrophic methanogenesis involves the disproportionation of methylated compounds, such as methanol, to methane and carbon dioxide. In this study, genetic in vivo analysis was utilized to characterize the C-1 oxidation branch of the methylotrophic pathway. It …
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Experimental investigations of isotopologue fractionation during microbial methanogenesis
… isotopologues ([delta]¹³CH₃D) during microbial methanogenesis. Chapter 2 uses batch and fed-batch culturing systems to investigate the effects of H₂ concentrations on isotopologue fractionation. The results from fed-batch experiments confirmed the previous observation of decoupled ¹³C/¹²C and …
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Biochemical and molecular characterization of tetrahydromethanopterin-dependent enzymes in methanogenesis
The biosynthetic pathway of methanogenesis proceeds via several bound intermediates. One of the coenzymes involved in this conversion is tetrahydromethanopterin (H$\sb4$MPT), a structural and biochemical analog of tetrahydrofolate (THF). Enzymes mediating these reactions in Methanobacterium …
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In Vitro Methanogenesis From Formaldehyde. Identification of Three Carbon-1 Intermediates of the Methanogenic Pathway
… units of different oxidation states to FAF. Methanogenesis from each derivative of FAF (formyl, methylene, and methyl) was kinetically comparable to CH(,3)-S-CoM. All the derivatives efficiently substituted for CH(,3)-S-CoM in the CH(,3)-S-CoM-stimulated conversion of CO(,2) to CH(,4), the …
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The Identification and Methylation of Coenzyme-M, a Cofactor Involved in Methanogenesis in Methanobacterium Strain M. O. H
Made available in DSpace on 2014-12-11T18:16:55Z (GMT). No. of bitstreams: 1 7412208.pdf: 4295071 bytes, checksum: 1ebcc21ae2a9a14a61b42bd5018257f9 (MD5) Previous issue date: 1973
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Denitrification, Dissimilatory Nitrate Reduction, and Methanogenesis in the Gut of Earthworms (Oligochaeta): Assessment of Greenhouse Gases and Genetic Markers
… both CH4 and nitrogenous gases, suggesting that methanogenesis and denitrification can be concomitant processes in the earthworm gut. This study demonstrated that (i) earthworms from all families, sizes, and feeding guilds can emit N2O and N2, (ii) substrate-derived and selectively activated …
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Carbon and electron flow via methanogenesis, So₄²⁻, NO₃⁻ and Fe³⁺ reduction in the anoxic hypolimnia of upper Mystic Lake
The profiles of CH₄ and CO₂ obtained by the use of a novel sampler, along with the profiles for nitrate (NO₃⁻), sulfate (So₄³⁻)and iron (Fe²⁺) were used to estimate the rates of the various anaerobic decomposition reactions during spring and fall stratification in Upper Mystic Lake. The equivalent …
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Effects of Macrolide Antimicrobials on Anaerobic Treatment Systems
KEYWORDS: ADM1, anaerobic, macrolide, methanogenesis, storage, SBR, tylosin.
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Insights into substrate utilization and transcriptional regulation in methanosarcina
… and methyl sulfides as substrates for methanogenesis. This dissertation presents biochemical and genetic studies on pyruvate utilization in Methanosarcina as a substrate for methanogenesis and the regulation of methylotrophic methanogenesis in M. acetivorans in an effort to further …
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Investigating the Distribution and Biosynthesis of Modified F<sub>430</sub> Cofactors in Methanogenic and Methanotrophic Archaea
Methanogenesis is the biological production of methane and is utilized by methanogenic archaea (methanogens) to generate energy. This process is responsible for 70% of total atmospheric methane, a potent greenhouse gas and an important energy source (natural gas). In the future, reversing …
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Cryogenic carbon cycling at an Icelandic glacier
… basal anoxia during summer facilitates methanogenesis resulting in large quantities of methane being discharged from beneath the glacier (flux range between 9,179 to 22,551 tonnes per year). Evidence suggests subglacial microbial acetoclastic methanogenesis is responsible with δ13C and …
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Formylmethanofuran formation in Methanobacterium thermoautotrophicum
The initial step of methanogenesis from CO$\sb2$ is the formation of formyl-methanofuran (formyl-MFR) from methanofuran, CO$\sb2$ and H$\sb2$. This reaction is not measurable in vitro unless activated. The enzymology, and the activation of this reaction were studied.
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Mechanisms of Methanogenic Inhibition in Advanced Anaerobic Digestion
… to ammonia inhibition, thus suggesting that methanogenesis by THD was less dependent on the NH₃-sensitive process of aceticlastic methanogenesis. Total ammonia nitrogen (TAN) and bicarbonate alkalinity were stoichiometrically produced from proteinaceous material during thermal hydrolytic …
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The effects and fate of selected veterinary antibiotics in two Missouri anaerobic swine lagoons
… storage. This work focused on the inhibition of methanogenesis by antibiotics, sorption of antibiotics to lagoon sediments, and hydrolysis, abiotic and biotic degradation of antibiotics in two central Missouri anaerobic lagoons used at two different confined animal feeding operations (CAFOs) …
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Impact of metallic nanoparticles on anaerobic digestion
… of 10 mg/kg solids resulted in inhibition of methanogenesis along with reduced biogas production, prolonged period of accumulation of VFAs, soluble COD, low pH, and decrease in methanogenic population. With the addition of the same amount of bulk silver ions (10 mg Ag/kg); however, there was …
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The Structure and Function of Component B of The Methylcoenzyme M Methylreductase System
… of a novel cofactor required for in vitro methanogenesis by the methylcoenzyme M methylreductase system were investigated. When the methylreductase system was first fractionated using cell extracts from Methanobacterium thermoautotrophicum strain $\Delta$H, three fractions were found to be …
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Insights into Adaptations of Biogas-Producing Microbial Communities from Taxonomic Profiling, Metagenomically Assembled Genomes and Analysis of the Methanogenic Isolate Methanothermobacter wolfeii SIV6
… and showed high expression of hydrogenotrophic methanogenesis enzymes. <br />Finally, detailed genome-based analyses of the archaeal isolate *Methanothermobacter wolfeii* SIV6, in combination with *in situ* metatranscriptomics and metagenomics, revealed specific genome features as potential …
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Greenhouse gas metabolizing prokaryotes in peatlands
… accumulation of fermentation products when methanogenesis was inhibited by Bromoethanesulfonate. Supplemental H2/CO2 and formate greatly stimulated methanogenesis, while acetate and methanol stimulated methanogenesis to a much lesser extent. A high family-level diversity of bacterial 16S …
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Electron Transport in Methanosarcina: Pathway Heterogeneity Within the Genus
Electron transport during methanogenesis in the freshwater methanogen Methanosarcina barkeri is known to utilize hydrogenases to transfer electrons from ferredoxin to methanophenazine. This thesis characterizes electron transport in the marine methanogen Methanosarcina acetivorans. Genomic …
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