2-Methylcitrate cycle: a well-regulated controller in Bacillus sporulation
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ABSTRACT:
ORGANISM(S): Bacillus thuringiensis BMB171
PROVIDER: GSE140317 | GEO | 2019/11/14
REPOSITORIES: GEO
Similar Datasets
Project description:Purpose: The goal of this study was to identify genes whose expression is induced during sporulation in a Spo0A-, M-OM-^CF-, M-OM-^CE-, M-OM-^CG-, and M-OM-^CK-dependent manner. Methods: Whole genome RNA sequencing was performed on wildtype, spo0A-, sigF-, sigE-, sigG-, and sigK- C. difficile strains (strain 630 background; JIR8094 = parent strain), and the transcriptional profiles of the different mutants during growth on 70:30 agar plates were determined using an Illumina HiSeq1000. Results: This analysis identified 185 genes whose expression is collectively activated by sporulation sigma factors: 150 were M-OM-^CF-dependent, 150 were M-OM-^CE-dependent, 30 were M-OM-^CG-dependent, and 31 were M-OM-^CK-dependent. A total of 237 genes were identified as requiring Spo0A for their expression when sporulation was induced on the 70:30 plates. Conclusions: These results provide the first genome-wide transcriptional analysis of genes whose expression is induced by specific sporulation sigma factors in the Clostridia and highlight that diverse mechanisms regulate sporulation sigma factor activity in the Firmicutes. For example, in contrast with the B. subtilis sporulation pathway, C. difficile M-OM-^CE was not required to fully activate M-OM-^CG, and M-OM-^CG was not required to activate M-OM-^CK. Wildtype, spo0A-, sigF-, sigE-, sigG-, and sigK- were streaked onto 70:30 plates in triplicate, and sporulation was induced. RNA from the three biological replicate samples was harvested, DNAse-I treated, and ribosomally depleted using Ribo-Zero kits. This RNA was transformed into cDNA, and the resulting libraries were subjected to paired end sequencing using an Illumina HiSeq 1000.
2013-08-10 | E-GEOD-45977 | biostudies-arrayexpress
Project description:Purpose: The goal of this study was to identify genes whose expression is induced during sporulation in a Spo0A-, σF-, σE-, σG-, and σK-dependent manner. Methods: Whole genome RNA sequencing was performed on wildtype, spo0A-, sigF-, sigE-, sigG-, and sigK- C. difficile strains (strain 630 background; JIR8094 = parent strain), and the transcriptional profiles of the different mutants during growth on 70:30 agar plates were determined using an Illumina HiSeq1000. Results: This analysis identified 185 genes whose expression is collectively activated by sporulation sigma factors: 150 were σF-dependent, 150 were σE-dependent, 30 were σG-dependent, and 31 were σK-dependent. A total of 237 genes were identified as requiring Spo0A for their expression when sporulation was induced on the 70:30 plates. Conclusions: These results provide the first genome-wide transcriptional analysis of genes whose expression is induced by specific sporulation sigma factors in the Clostridia and highlight that diverse mechanisms regulate sporulation sigma factor activity in the Firmicutes. For example, in contrast with the B. subtilis sporulation pathway, C. difficile σE was not required to fully activate σG, and σG was not required to activate σK.
2013-08-10 | GSE45977 | GEO
Project description:The Alphaproteobacterium Caulobacter crescentus inhabits low-nutrient environments and can tolerate certain levels of heavy metal in these sites. It has been reported that C. crescentus responds to chromium exposure by altering expression of a large number of genes. In this work, we showed that the ECF sigma factor SigF is one of the regulatory proteins involved in the control of this transcriptional response. Microarray experiments from cells under dichromate stress showed that SigF controls a small regulon consisting of seven genes. Promoter analyses revealed that a conserved SigF-dependent sequence is located upstream of all but one gene of this regulon. Surprisingly, sigF itself was not found to be strongly auto-regulated under dichromate exposure. Furthermore, we showed that the second gene (CC3252) in the sigF operon acts as a negative regulator of SigF function, as overexpression of this putative membrane protein abolishes the transcriptional activation of sigF and its regulon under dichromate stress. Additionally, we found that substitution of one or both the conserved cysteines in the protein encoded by CC3252 (C131 and C181) affects the ability of this protein in maintaining expression of SigF-dependent genes at basal levels. Interestingly, we showed that the activation of SigF is not caused by reactive oxygen species generated as a consequence of dichromate exposure. Therefore, dichromate most probably may lead to conformational changes in the putative anti-sigma factor CC3252, releasing SigF to bind RNA polymerase core and drive transcription of its regulon.
2012-10-02 | GSE32406 | GEO
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:2-Methylcitrate cycle: a well-regulated controller in Bacillus sporulation
| PRJNA589283 | ENA
Project description:The Alphaproteobacterium Caulobacter crescentus inhabits low-nutrient environments and can tolerate certain levels of heavy metal in these sites. It has been reported that C. crescentus responds to chromium exposure by altering expression of a large number of genes. In this work, we showed that the ECF sigma factor SigF is one of the regulatory proteins involved in the control of this transcriptional response. Microarray experiments from cells under dichromate stress showed that SigF controls a small regulon consisting of seven genes. Promoter analyses revealed that a conserved SigF-dependent sequence is located upstream of all but one gene of this regulon. Surprisingly, sigF itself was not found to be strongly auto-regulated under dichromate exposure. Furthermore, we showed that the second gene (CC3252) in the sigF operon acts as a negative regulator of SigF function, as overexpression of this putative membrane protein abolishes the transcriptional activation of sigF and its regulon under dichromate stress. Additionally, we found that substitution of one or both the conserved cysteines in the protein encoded by CC3252 (C131 and C181) affects the ability of this protein in maintaining expression of SigF-dependent genes at basal levels. Interestingly, we showed that the activation of SigF is not caused by reactive oxygen species generated as a consequence of dichromate exposure. Therefore, dichromate most probably may lead to conformational changes in the putative anti-sigma factor CC3252, releasing SigF to bind RNA polymerase core and drive transcription of its regulon. Three replicates perfomed with independent biological samples
2012-10-02 | E-GEOD-32406 | 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 M-OM-^CF, then M-OM-^CE, then M-OM-^CG, and finally M-OM-^CK. The goal of this study is to determine the regulons of 4 of these transcription/sigma factors (Spo0A, M-OM-^CF, M-OM-^CE, and M-OM-^CG) and compare them to those in B. subtilis. To accomplish this goal, individual mutant strains were created for Spo0A, M-OM-^CF, M-OM-^CE, and M-OM-^CG, 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 M-OM-^CF mutant and the M-OM-^CE 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. Four transcription/sigma factor regulons were investigated: Spo0A, M-OM-^CF, M-OM-^CE, and M-OM-^CG. For Spo0A, two comparison were made: Spo0A mutant vs M-OM-^CF mutant and Spo0A mutant vs M-OM-^CE mutant. For M-OM-^CF, two comparison were also made: M-OM-^CF mutant vs M-OM-^CE mutant and M-OM-^CF mutant vs M-OM-^CG mutant. Finally for M-OM-^CE and M-OM-^CG, only one comparison for each was made: M-OM-^CE mutant vs M-OM-^CG mutant and M-OM-^CG mutant vs wild-type, respectively. For each comparison, 4 timepoints were analyzed, and dye-swaps were prepared for each timepoint comparison. Timepoints were chosen based on when each transcription/sigma factor was expected to be active, based on a previous study [Jones, SW, et al. Genome Biol. 2008;9(7):R114.].
2011-02-28 | E-GEOD-24103 | biostudies-arrayexpress
Project description:The universally conserved protein Elongation Factor P facilitates translation at amino acids that form peptide bonds with low efficiency, particularly poly-proline tracts. Despite its wide conservation, it is not essential in most bacteria and its physiological role remains unclear. Here, we show that EF-P affects the process of sporulation initiation in the bacterium Bacillus subtilis. We observe that lack of EF-P delays expression of sporulation-specific genes. Using ribosome profiling, we observe that expression of spo0A, encoding a transcription factor that functions as the master regulator of sporulation, is lower in a ∆efp strain as compared to the wildtype. Ectopic expression of Spo0A rescues the sporulation initiation phenotype, indicating that reduced spo0A expression explains the sporulation defect in ∆efp cells. Since Spo0A is the earliest sporulation transcription factor, these data suggest that sporulation initiation can be delayed when protein synthesis is impaired.
2023-01-04 | GSE222121 | GEO
Project description:To perform natural transformation, one of the three main Horizontal Gene Transfer mechanisms, bacteria need to enter a physiological differentiated state called genetic competence. Interestingly, new bacteria displaying such aptitude are often discovered, and one of the latest is the human pathogen Staphylococcus aureus. Here, we developed a new protocol, based on planktonic cells cultures, leading to a large percentage of the population activating competence development and a significant improvement of S. aureus natural transformation efficiencies. Taking advantage of these new conditions, we performed transcriptomics analyses to characterize each central competence regulators regulon. SigH and ComK1 were both found essential for activating natural transformation genes but also important for activation or repression of peripheral functions. Even though ComK2 was not found important for the control of transformation genes, its regulon showed an important overlap with that of SigH and ComK1. Finally, we showed how microaerobic conditions, sensed by the SrrAB two-component system, was key to activate competence in S. aureus.
2023-04-26 | PXD040550 | Pride
Project description:Mycobacterium avium subspecies paratuberculosis (a.k.a. M. paratuberculosis) causes Johne’s disease, an enteric infection in cattle and other ruminants, greatly afflicting the dairy industry worldwide. Once inside the cell, M. paratuberculosis is known to survive harsh microenvironments, especially those inside activated macrophages. To improve our understanding of M. paratuberculosis pathogenesis, we examined the phagosome maturation associated with transcriptional responses of M. paratuberculosis during macrophage infection. Monitoring cellular markers, only live M. paratuberculosis bacilli were able to prevent phagosome maturation and reduce its acidification. On the transcriptional level, over 300 of M. paratuberculosis genes were significantly, differentially regulated in both naïve and IFN-γ-activated macrophages. These genes include the sigma factor H (sigH) that was shown to be important during persistent infection in M. tuberculosis. Interestingly, a sigH-knockout mutant showed increased sensitivity to a sustained level of thiol-specific oxidative stress. Large-scale RNA sequence analysis revealed that a large number of genes belong to the sigH regulon, especially following diamide stress. Genes involved in oxidative stress and virulence were among the induced genes in the sigH regulon with a putative consensus sequence for SigH binding was recognized in a subset of these genes (N=30), suggesting direct regulation with SigH. Finally, mice infections showed a significant attenuation of the ∆sigH mutant compared to its parental strain suggesting a role for sigH in M. paratuberculosis virulence. Such analysis could identify potential targets for further testing as vaccine candidates against Johne’s disease.
2012-12-29 | GSE43182 | GEO