Clostridium ljungdahlii DSM 13528
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA13492 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Halophilic acetogenic bacterium
| PRJNA32769 | ENA
Project description:Acetogenic bacteria utilize cellular redox energy to convert CO2 to acetate using the Wood-Ljungdahl (WL) pathway. Such redox energy can be derived from electrons generated from H2 as well as inorganic materials such as photo-responsive semiconductors. To reveal how acetogenic bacteria utilize electrons generated from external energy sources to reduce CO2, we developed a nanoparticle-microbe hybrid system and generated RNA-seq results.
2020-09-09 | GSE157613 | GEO
Project description:To explore the cross feeding interactions between the acetogenic human colonic bacterium Blautia hydrogenotrophica and the nutritional specialist amyloltic bacterium Ruminococcus bromii in a continuous culture system utilising transcriptome analysis.
2019-03-19 | E-MTAB-6544 | biostudies-arrayexpress
Project description:Clostridium ljungdahlii DSM 13528 Transcriptome or Gene expression
| PRJNA202264 | ENA
Project description:Clostridium autoethanogenum and Clostridium ljungdahlii are physiologically and genetically very similar strict anaerobic acetogens capable of growth on carbon monoxide as sole carbon source. While exact nutritional requirements have not been reported, we observed that for growth, the addition of vitamins to media already containing yeast extract was required, an indication that these are fastidious microorganisms. Elimination of complex components and individual vitamins from the medium revealed that the only organic compounds required for growth were pantothenate, biotin and thiamine. Analysis of the genome sequences revealed that three genes were missing from pantothenate and thiamine biosynthetic pathways, and five genes were absent from the pathway for biotin biosynthesis. Prototrophy in C. autoethanogenum and C. ljungdahlii for pantothenate was obtained by the introduction of plasmids carrying the heterologous gene clusters panBCD from Clostridium acetobutylicum, and for thiamine by the introduction of the thiC-purF operon from Clostridium ragsdalei. Integration of panBCD into the chromosome through allele-coupled exchange also conveyed prototrophy. C. autoethanogenum was converted to biotin prototrophy with gene sets bioBDF and bioHCA from Desulfotomaculum nigrificans strain CO-1-SRB, on plasmid and integrated in the chromosome. The genes could be used as auxotrophic selection markers in recombinant DNA technology. Additionally, transformation with a subset of the genes for pantothenate biosynthesis extended selection options with the pantothenate precursors pantolactone and/or beta-alanine. Similarly, growth was obtained with the biotin precursor pimelate combined with genes bioYDA from C. acetobutylicum. The work raises questions whether alternative steps exist in biotin and thiamine biosynthesis pathways in these acetogens.
| S-EPMC6505512 | biostudies-literature
Project description:Acetate is a simple carboxylic acid that is synthesized in various microorganisms. Although acetate toxicity and tolerance have been studied in many microorganisms, little is known about the effects of exogenous acetate on the cell growth of acetogenic bacteria. In this study, we report the phenotypic changes that occurred in the acetogenic bacterium Clostridium sp. AWRP as a result of an adaptive laboratory evolution under acetate challenge. When compared with the wild-type strain, the acetate-adapted strain displayed a tolerance to acetate up to 10 g L-1 and higher biomass yields in batch cultures, although the metabolite profiles greatly varied depending on culture conditions. Interestingly, genome sequencing revealed that the adapted strain harbored three point mutations in the genes encoding an electron-bifurcating hydrogenase, which is crucial to its autotrophic growth on CO2 + H2, in addition to one in the dnaK gene. Transcriptome analysis revealed the global change in the gene expression profile of the acetate-adapted strain. Strikingly, most genes involved in CO2-fixing Wood-Ljungdahl pathway and auxiliary pathways for energy conservation (e.g., Rnf complex, Nfn, etc.) were significantly down-regulated. In addition, we observed that a couple of metabolic pathways associated with dissimilation of nucleosides and carbohydrates were significantly up-regulated in the acetate-adapted strain as well as several amino acid biosynthetic pathways, indicating that the strain might increase its fitness by utilizing organic substrates in response to the down-regulation of carbon fixation. Further investigation into the carbon fixation degeneration of the acetate-adapted strain will provide practical implications in CO2 + H2 fermentation using acetogenic bacteria for long-term continuous fermentation. The transcriptome profiles of the wild-type Clostridium sp. AWRP and its acetate-tolerant derivative 46T-a were compared.
2022-06-26 | GSE206757 | GEO
Project description:Clostridium thermocellum is a promising CBP candidate organism capable of directly converting lignocellulosic biomass to ethanol. Low yields, productivities and growth inhibition prevent industrial deployment of this organism for commodity fuel production. Symptoms of potential redox imbalance such as incomplete substrate utilization, and fermentation products characteristic of overflow metabolism, have been observed during growth. This perceived redox imbalance may be in part responsible for the mentioned bioproductivity limitations. Toward better understanding the redox metabolism of C. thermocellum, we analyzed gene expression, using microarrays, during addition of two stress chemicals (methyl viologen and hydrogen peroxide) which we observed to change fermentation redox potential.
2015-07-29 | GSE71465 | GEO
Project description:Clostridium ljungdahlii is an important synthesis gas-fermenting bacterium used in the biofuels industry, and a preliminary investigation showed that it has some tolerance to oxygen when cultured in rich mixotrophic medium. Batch cultures not only continue to grow and consume H2, CO, and fructose after 8% O2 exposure, but fermentation product analysis revealed an increase in ethanol concentration and decreased acetate concentration compared to non-oxygen-exposed cultures. In this study, the mechanisms for higher ethanol production and oxygen/reactive oxygen species (ROS) detoxification were identified using a combination of fermentation, transcriptome sequencing (RNA-seq) differential expression, and enzyme activity analyses. The results indicate that the higher ethanol and lower acetate concentrations were due to the carboxylic acid reductase activity of a more highly expressed predicted aldehyde oxidoreductase (CLJU_c24130) and that C. ljungdahlii's primary defense upon oxygen exposure is a predicted rubrerythrin (CLJU_c39340). The metabolic responses of higher ethanol production and oxygen/ROS detoxification were found to be linked by cofactor management and substrate and energy metabolism. This study contributes new insights into the physiology and metabolism of C. ljungdahlii and provides new genetic targets to generate C. ljungdahlii strains that produce more ethanol and are more tolerant to syngas contaminants.
| S-EPMC4644658 | biostudies-literature