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Showing 1 to 20 of 20 for “"solvent production"”.
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Nitrogen Metabolism and Solvent Production in Clostridium Beijerinckii Nrrl B593
The onset of solvent production by the clostridia involves regulation at the transcriptional level. The signal triggering the onset has not been identified, but redox and energetic states have been suggested as possible factors. Because several solvent-producing clostridia, including Clostridium …
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Studies on the regulation of solvent production and endospore formation in Clostridium Acetobutylicum P262
… was to characterise the relationships between solventogenesis and endospore formation in Clostridium acetobutylicum strain P262. Growth and endospore formation was monitored in a number of complex and minimal media and as a result of these studies a new defined sporulation medium was developed. …
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Development of a reporter system for the study of gene expression for solvent production in Clostridium beijerinckii NRRL B592 and Clostridium acetobutylicum ATCC 824
… The lack of a good reporter system for the solvent-producing clostridia hindered the progress of research in this area. The objective of this study was to develop a reporter system to facilitate the elucidation of the control mechanism for the expression of solvent-producing genes. A …
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Genetic and Physiological Characterization of Clostridium Beijerinckii BA101 and NCIMB 8052
… acetate in MP2 medium was also able to stabilize solvent production by C. beijerinckii BA101, a hypersolvent producing mutant derived from NCIMB 8052. Moreover, BA101 demonstrated a greater increase in solvent production than NCIMB 8052 when acetate was added into MP2 medium. During the …
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Mathematical modeling of the acetone-butanol fermentation for the purposes of bioreactor design
… renewed interest as a process for large scale solvent production. The fermentation kinetics have been modeled as functions of substrate, butyrate, and butanol concentrations and pH. These models have been applied to simulate batch, single stage stirred continuous, and two stage stirred …
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Biochemistry and physiology of Clostridium acetobutylicum relative to its fermentation shift and to culture degeneration
… ATCC 824, and several strains defective in solvent production (a butanol tolerant, low butanol producing derivative, SA-2; a butanol dehydrogenase minus derivative, AA-115; a degenerative derivative, DG; and C. butyricum ATCC 19398).
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A reassessment of the production of acetone and butanol by Clostridium acetobutylicum in continuous culture
The production of acetone and butanol by Clostridium acetobutylicum P 262 was studied in continuous culture under conditions where the nutrients were present in excess of the requirements and the cell growth was limited by the products formed during the fermentation. This system differs from most …
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Transcriptomic analyses of Clostridium beijerinckii NCIMB 8052 during transition from acidogenesis to solventogenesis and under butyrate supplemented conditions
… is among the prominent species for biobutanol production as it demonstrates a broad substrate range for growth and solvent production. Although the transcriptome structure and transcriptional profiling are essential for understanding the functional and regulatory network of the genome and …
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Enzymology of butanol formation in Clostridium Beijerinckii
… an investigation of the expression of solvent forming enzymes and purification and characterization of butanol-forming enzymes. More sensitive and accurate procedures for the determination of acids and solvents in cultures have been developed, which led to the recognition of the onset …
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Genetic Manipulation and Characterization of Solvent-Producing Clostridia
… work has been done on the formulation of a new solventogenic clostridial fermentation medium based on the use of corn steep liquor (CSL). CSL is a by-product of the corn wet-milling industry, and has been used primarily as a feed supplement in the livestock industry. This nutrient-rich medium is …
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Molecular characterization of three linked genes, fixB, βshbd and adh1 from Clostridium acetobutylicum P262
… and it has been used in the industrial production of acetone and butanol for many years. The aim of this study was to characterize the upstream region of the βhbd gene which is linked to the adh1 gene, and to investigate the expression of these linked genes by transcriptional analysis. …
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Fermentation studies on Clostridium acetabutylicum
… spore preparation in distilled water gave solvent yields comparable to the yields obtained in the commercial ABE process. A laboratory inoculation procedure was developed which avoided the lengthy culture build-up procedures presently utilised. An investigation into solvent production by …
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The Cloning of a Putative Regulatory Gene and the sol Region from Clostridium beijerinckii
The solvent-producing clostridia are well known for their ability to produce acetone, butanol and isopropanol in industrial fermentation. Production of these compounds occurs in cells that have completed a metabolic switch under specific growth conditions. Knowledge of the regulation of the …
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The characterization of Clostridium beijerinckii NRRL B592 cells transformed with plasmids containing the butanol-production genes under the control of constitutive promoters
… industrial chemicals are traditionally known as solvents. The regulation of solventogenic fermentation is linked to the onset of sporulation, so that by the time the organism begins to produce solvents, it is also entering into spore formation and metabolic slowdown. The goal of this research …
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Hydrogenase of Clostridium acetobutylicum ATCC 824
… remain near 4.5, the metabolism switches to the production of the neutral compounds (solvents) - acetone, n-butanol, and ethanol. The two metabolic phases are known as the acidogenic and solventogenic phases. The enzyme hydrogenase plays an important role in this bacterium because it converts …
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Genetic Characterization and Manipulation of Solvent -Producing Clostridia
… level were responsible for the increased butanol production exhibited by C. beijerinckii BA101 relative to the wild type C. beijerinckii NCMIB 8052. No observable differences were detected in the sequences of the structural genes and regions upstream of the sol operons. The shuttle vector pYL102E …
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CoA-transferase and 3-hydroxybutyryl-CoA dehydrogenase: acetoacetyl-CoA-reacting enzymes from Clostridium beijerinckii NRRL B593
… 45-fold to apparent homogeneity from the solvent-producing anaerobe Clostridium beijerinckii strain NRRL B593. The identities of 34 of the 35 N-terminal amino acid residues have been determined. The enzyme exhibited a native M<sub>r</sub> of 213,000 and a subunit M<sub>r</sub> of 30,800. …
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Production of 1-butanol and butanol isomers by metabolically engineered Clostridium beijerinckii and Saccharomyces cerevisiae
… ABE (acetone-butanol-ethanol) fermentation by solventogenic clostridia such as Clostridium beijerinckii. Although the ABE fermentation is considered as a promising process for butanol production, current drawbacks in the ABE fermentation include low titer, yield, and productivity of solvent …
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An Improved Vapour Solvent Injection Technique for Enhanced Heavy Oil Recovery
… 10 metres. Non-thermal methods, such as cold production, and solvent-based methods, are the alternative approaches. Cold production, such as cold heavy oil production (CHOP) and cold heavy oil production with sands (CHOPS), suffers low recovery factor, which is approximate 5–10% of original …
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Studies on the regulation of nitrogen metabolism in clostridium acetobutylicum NCP 262 and clostridium beijerinckii NCIMB 8052
… Clostridium acetobutylicum strains with improved solventogenic capabilities through genetic manipulation, a thorough understanding of the mechanisms governing solvent production is required. Nitrogen metabolism has been shown to be important in the regulation of sporulation and solventogenesis, …