Metabolite stress response to butanol in Clostridium acetobutylicum ATCC 824
Ontology highlight
ABSTRACT:
ORGANISM(S): Clostridium acetobutylicum ATCC 824
PROVIDER: GSE48031 | GEO | 2013/08/20
SECONDARY ACCESSION(S): PRJNA208743
REPOSITORIES: GEO
Similar Datasets
Project description:Clostridium acetobutylicum is a Gram positive, endospore forming firmicute that has been known as the model organims for ABE (acetone-butanol-ethanol) fermentation. With its ability to consume a wide variety of substrates, C. acetobutylicum carries out a biphasic ABE fermentation, which consists of the acidogenic growth phase with the formation of butyric acid and acetic acid, followed by the solventogenic stationary phase with the formation of acetone, butanol and ethanol, characterised by the reassimilation of acids. The production butanol is of renewed ineterest both as a potential biofuel and bulk chemical production. Both butanol and butyric acid posses toxic characteristic and here, we focus on understanding and modeling the stress response of C. acetobutylicum to one of the two important toxic metabolites: butyric acid.
2013-08-20 | GSE48039 | GEO
Project description:Clostridium acetobutylicum is a Gram positive, endospore forming firmicute that has been known as the model organims for ABE (acetone-butanol-ethanol) fermentation. With its ability to consume a wide variety of substrates, C. acetobutylicum carries out a biphasic ABE fermentation, which consists of the acidogenic growth phase with the formation of butyric acid and acetic acid, followed by the solventogenic stationary phase with the formation of acetone, butanol and ethanol, characterised by the reassimilation of acids. The production butanol is of renewed ineterest both as a potential biofuel and bulk chemical production. Both butanol and butyrate posses toxic characteristic and here, we focus on understanding and modeling the stress response of C. acetobutylicum to one of the two important toxic metabolites: butanol. C. acetobutylicum cultures were grown, three biological replicates, to mid-exponential phase and then stressed with four levels of butanol (0 mM - No stress; 30 mM - Low stress; 60 mM - Medium stress; & 90 mM - High stress). Samples were collected following the stress at 0, 15, 30, 45, 60 and 75 min, post stress. These sampling times, which are of the order of the doubling time of these cells, were meant to capture largely the direct and immediate impact of these stresses on gene expression. The RNA extracted from two biological replicates were used for microarray hybridization foloowing cDNA generationa nd labelling using Agilent 44K arrays, while the third was used for q-RT-PCR validation. For each stress level, 6 time points with 2 biological replicates and dye swaps (Cy3/Cy5) were prepared for comparison. The hybridization was perfomed against an equal amount of oppositely labeled cDNA from common reference pool prepared using equal amounts of labeled cDNA from all four stress levels.
2013-08-20 | E-GEOD-48031 | biostudies-arrayexpress
Project description:Clostridium acetobutylicum is a Gram positive, endospore forming firmicute that has been known as the model organims for ABE (acetone-butanol-ethanol) fermentation. With its ability to consume a wide variety of substrates, C. acetobutylicum carries out a biphasic ABE fermentation, which consists of the acidogenic growth phase with the formation of butyric acid and acetic acid, followed by the solventogenic stationary phase with the formation of acetone, butanol and ethanol, characterised by the reassimilation of acids. The production butanol is of renewed ineterest both as a potential biofuel and bulk chemical production. Both butanol and butyric acid posses toxic characteristic and here, we focus on understanding and modeling the stress response of C. acetobutylicum to one of the two important toxic metabolites: butyric acid. C. acetobutylicum cultures were grown, three biological replicates, to mid-exponential phase and then stressed with four levels of butyric acid (0 mM - No stress; 30 mM - Low stress; 40 mM - Medium stress; & 50 mM - High stress). Butyric acid was pH adjusted with 10M KOH to match the pH of the cultures, prior to addition. Samples were collected following the stress at 0, 15, 30, 45, 60 and 75 min, post stress. These sampling times, which are of the order of the doubling time of these cells, were meant to capture largely the direct and immediate impact of these stresses on gene expression. The RNA extracted from two biological replicates were used for microarray hybridization foloowing cDNA generation and labelling using Agilent 44K arrays, while the third was used for q-RT-PCR validation. For each stress level, 6 time points with 2 biological replicates and dye swaps (Cy3/Cy5) were prepared for comparison. The hybridization was perfomed against an equal amount of oppositely labeled cDNA from common reference pool prepared using equal amounts of labeled cDNA from all four stress levels.
2013-08-20 | E-GEOD-48039 | biostudies-arrayexpress
Project description:Artificial electron carriers have been widely used to shift the solvent ratio towards butanol in acetone-butanol-ethanol (ABE) fermentation of solventogenic clostridia according to decreased hydrogen production. In this study, first insights on the molecular level were gained to explore the effect of methyl viologen addition to cultures of Clostridium acetobutylicum. Employing batch fermentation in mineral salts medium, the butanol:acetone ratio was successively increased from 2.3 to 12.4 on a 100 ml scale in serum bottles and from 1.4 to 16.5 on a 1,300 ml scale in bioreactors, respectively. The latter cultures were used for DNA microarray analyses to provide new information on the transcriptional changes referring to methyl viologen exposure and thus, exhibing gene expression patterns according to the manipulation of the cellular redox balance.
2012-03-31 | E-MEXP-3417 | biostudies-arrayexpress
Project description:Clostridium acetobutylicum is characterized by its acetone-butanol (AB) fermentation which <br>can be reproducibly established under continuous grow conditions in a chemostat. <br>At pH 5.7 cells show typical acidogenic metabolism and mainly produce the acids <br>acetate and butyrate. After lowering and further control the external pH at 4.5 <br>the exponentially growing cells switch towards stable solvent production with the <br>dominating fermentation products acetone and butanol. <br>Here we present a comprehensive comparison of proteome and transcriptome <br>data of continuously growing cells of C. acetobutylicum in a chemostat culture <br>under phosphate limitation at pH 5.7 (acidogenesis) and pH 4.5 (solventogenesis).
2010-11-10 | E-MEXP-2503 | biostudies-arrayexpress
Project description:Clostridium acetobutylicum, the endospore-forming anaerobe best known for its ABE (acetone-butanol-ethanol) fermentation, has received renewed attention recently for the biological production of butanol, both for bulk chemical production and as a potential biofuel. With butanol production in mind, most of the recent research on C. acetobutylicum has focused on increasing butanol production, tolerance to butanol, and optimizing it for various substrates. However, an equally important trait, though less understood, is its sporulation program, which it coupled to solvent formation. The model organism for endospore formation is Bacillus subtilis, but significant physiological, metabolic, and genomic differences exist between the two organisms. Despite these differences, the major sporulation-related transcription/sigma factors are conserved between the two species. These transcription/sigma factors are activated in a cascade manner such that Spo0A becomes active first, followed by σF, then σE, then σG, and finally σK. The goal of this study is to determine the regulons of 4 of these transcription/sigma factors (Spo0A, σF, σE, and σG) and compare them to those in B. subtilis. To accomplish this goal, individual mutant strains were created for Spo0A, σF, σE, and σG, in which the transcription/sigma factor is silenced. These mutants were then compared transcriptionally using microarrays to determine the regulon of each transcription/sigma factor. To help avoid false positives, comparisons were made between strains in which the downstream transcription/sigma factor is silenced (e.g., for the Spo0A regulon, the Spo0A mutant was compared against the σF mutant and the σE mutant, since they are both upregulated by Spo0A) rather than just the WT. For each regulon, 4 timepoints were taken, since it is very difficult to synchronize sporulation in C. acetobutylicum cultures, and dye-swaps were prepared for each timepoint.
2011-02-28 | GSE24103 | GEO
Project description:Furfural is the prevalent microbial inhibitor generated during pretreatment and hydrolysis of lignocellulosic biomass to monomeric sugars, but the molecular response of Clostridium beijerinckii NCIMB 8052 to this compound is unknown. To discern the effect of furfural on C. beijerinckii and to gain insights into the molecular mechanisms of action and detoxification, we studied the physiological changes of furfural-stressed cultures during acetone-butanol-ethanol (ABE) fermentation, and profiled differentially expressed genes by genome-wide transcriptional analysis. C. beijerinckii exposed to furfural stress during the acidogenic growth phase produced 13% more ABE than the unstressed control. The growth and ABE by C. beijerinckii ceased following exposure to furfural stress during the solventogenic growth phase. By comparing gene expression of furfural-stressed cultures to that of the unstressed control, at both the acidogenic and solventogenic phases, we ascertained that furfural induces expression of several genes including those that code for heat shock proteins, redox enzymes and cofactor associated proteins, and ATP-binding cassette transporters, and represses genes belonging to the phosphotransferase system, two-component system, chemotaxis and cell motility. Based on these results, we discuss the underpinning for furfural-mediated change in ABE fermentation by the solventogenic Clostridium species.
2012-12-06 | GSE42597 | GEO
Project description:Clostridium beijerinckii is an anaerobic strain and well known for acetone-ethanol-butanol (ABE) fermentation using carbohydrates derived from cellulose or starch. During ABE fermentation, various byproducts are formed, mainly including acids (acetate, butyrate and lactate) and gas (hydrogen and carbon dioxide). recently, we found that Clostridium beijerinckii is able to produce a new product that had never been reported before and tightly regulated by pH and nitrogen source.
2021-12-02 | E-MTAB-11154 | biostudies-arrayexpress
Project description:Furfural is the prevalent microbial inhibitor generated during pretreatment and hydrolysis of lignocellulosic biomass to monomeric sugars, but the molecular response of Clostridium beijerinckii NCIMB 8052 to this compound is unknown. To discern the effect of furfural on C. beijerinckii and to gain insights into the molecular mechanisms of action and detoxification, we studied the physiological changes of furfural-stressed cultures during acetone-butanol-ethanol (ABE) fermentation, and profiled differentially expressed genes by genome-wide transcriptional analysis. C. beijerinckii exposed to furfural stress during the acidogenic growth phase produced 13% more ABE than the unstressed control. The growth and ABE by C. beijerinckii ceased following exposure to furfural stress during the solventogenic growth phase. By comparing gene expression of furfural-stressed cultures to that of the unstressed control, at both the acidogenic and solventogenic phases, we ascertained that furfural induces expression of several genes including those that code for heat shock proteins, redox enzymes and cofactor associated proteins, and ATP-binding cassette transporters, and represses genes belonging to the phosphotransferase system, two-component system, chemotaxis and cell motility. Based on these results, we discuss the underpinning for furfural-mediated change in ABE fermentation by the solventogenic Clostridium species. C. beijerinckii 8052 pre-culture was incubated anaerobically to attain acidogenic or solventogenic growth phase. The culture was then subdivided into two bottles. One bottle was challenged with furfural and the other bottle was left unchallenged. After 3 h growth, C. beijerinckii 8052 samples were collected, during which the original concentration of furfural in the growth medium was reduced to more than half. Total RNA was isolated, purified, converted to enriched mRNA, and dye-coupled (Alexa Fluor 555) complementary cRNA. This was followed by hybridization and microarray data analysis.
2012-12-06 | E-GEOD-42597 | biostudies-arrayexpress
Project description:Clostridium acetobutylicum is a Gram-positive, endospore-forming bacterium that is considered as a strict anaerobe. It ferments sugars to the organic acids acetate and butyrate or shifts to formation of the solvents - ethanol, butanol and acetone. In most bacteria the major regulator of iron homeostasis is Fur (ferric uptake regulator). Analysis of the genome of Clostridium acetobutylicum has revealed three genes encoding Fur-like proteins. The amino acid sequece of one of them showed 70% similarity to the Fur protein of the closely related Bacillus subtilis.<br>Thus, to gain insight into the role of Fur and the mechanisms for maintenance of iron homeostasis in this strict anaerobic organism, we determined its transcriptional profile in response to iron limitation and inactivation of fur.
2012-03-30 | E-MEXP-3401 | biostudies-arrayexpress