Cellobiose-mediated gene expression in Streptococcus pneumoniae and the repressor function of the novel GntR-type regulator BguR
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ABSTRACT:
ORGANISM(S): Streptococcus pneumoniae D39
PROVIDER: GSE43345 | GEO | 2013/02/20
SECONDARY ACCESSION(S): PRJNA185486
REPOSITORIES: GEO
Similar Datasets
Project description:Comparison of the Streptococcus pneumoniae D39 wild type in M17 medium+ 0.5 % (w/v) Cellobiose (CM17) compared to M17 medium+ 0.5 % (w/v) Glucose (GM17) hervasted at time point T1 The human pathogen Streptococcus pneumoniae has the ability to use the carbon- and energy source cellobiose due to the presence of a cellobiose-utilizing gene cluster (cel locus) in its genome. This system is regulated by the cellobiose-dependent transcriptional activator CelR, which has been previously shown to contribute to pneumococcal virulence. To get a broader understanding of the response of S. pneumoniae to cellobiose, we compared the pneumococcal transcriptome during growth on glucose as the main carbon source to that with cellobiose as the main carbon source. The expression of various carbon metabolic genes was altered, including a PTS operon (which we here denote as the bgu operon) that has high similarity with the cel locus. In contrast to the cel locus, the bgu operon is conserved in all sequenced strains of S. pneumoniae, indicating an important physiological function in the lifestyle of pneumococci. We next characterized the transcriptional regulation of the bgu operon in more detail. Its expression was increased in the presence of cellobiose, and decreased in the presence of glucose. A novel GntR-type transcriptional regulator (which we here denote as BguR) was shown to act as a transcriptional repressor of the bgu operon and its repressive effect was relieved in the presence of cellobiose. BguR-dependent repression was demonstrated to be mediated by a 20-bp DNA operator site (5M-bM-^@M-^Y-AAAAATGTCTAGACAAATTT-3M-bM-^@M-^Y) present in PbguA as verified by promoter truncation experiments. In conclusion, we have identified a new cellobiose-responsive PTS operon, together with its transcriptional regulator in S. pneumoniae. Two condition design, comparison of one strain including a dye swap
2013-02-20 | E-GEOD-43343 | biostudies-arrayexpress
Project description:Comparison of the Streptococcus pneumoniae D39 wild type in M17 medium+ 0.5 % (w/v) Cellobiose (CM17) compared to M17 medium+ 0.5 % (w/v) Glucose (GM17) hervasted at time point T2 The human pathogen Streptococcus pneumoniae has the ability to use the carbon- and energy source cellobiose due to the presence of a cellobiose-utilizing gene cluster (cel locus) in its genome. This system is regulated by the cellobiose-dependent transcriptional activator CelR, which has been previously shown to contribute to pneumococcal virulence. To get a broader understanding of the response of S. pneumoniae to cellobiose, we compared the pneumococcal transcriptome during growth on glucose as the main carbon source to that with cellobiose as the main carbon source. The expression of various carbon metabolic genes was altered, including a PTS operon (which we here denote as the bgu operon) that has high similarity with the cel locus. In contrast to the cel locus, the bgu operon is conserved in all sequenced strains of S. pneumoniae, indicating an important physiological function in the lifestyle of pneumococci. We next characterized the transcriptional regulation of the bgu operon in more detail. Its expression was increased in the presence of cellobiose, and decreased in the presence of glucose. A novel GntR-type transcriptional regulator (which we here denote as BguR) was shown to act as a transcriptional repressor of the bgu operon and its repressive effect was relieved in the presence of cellobiose. BguR-dependent repression was demonstrated to be mediated by a 20-bp DNA operator site (5M-bM-^@M-^Y-AAAAATGTCTAGACAAATTT-3M-bM-^@M-^Y) present in PbguA as verified by promoter truncation experiments. In conclusion, we have identified a new cellobiose-responsive PTS operon, together with its transcriptional regulator in S. pneumoniae. Two condition design, comparison of one strain including a dye swap
2013-02-20 | E-GEOD-43344 | biostudies-arrayexpress
Project description:Transcriptome comparison of bguR mutant to wild-type in the Streptococcus pneumoniae D39 grown in GM17 The human pathogen Streptococcus pneumoniae has the ability to use the carbon- and energy source cellobiose due to the presence of a cellobiose-utilizing gene cluster (cel locus) in its genome. This system is regulated by the cellobiose-dependent transcriptional activator CelR, which has been previously shown to contribute to pneumococcal virulence. To get a broader understanding of the response of S. pneumoniae to cellobiose, we compared the pneumococcal transcriptome during growth on glucose as the main carbon source to that with cellobiose as the main carbon source. The expression of various carbon metabolic genes was altered, including a PTS operon (which we here denote as the bgu operon) that has high similarity with the cel locus. In contrast to the cel locus, the bgu operon is conserved in all sequenced strains of S. pneumoniae, indicating an important physiological function in the lifestyle of pneumococci. We next characterized the transcriptional regulation of the bgu operon in more detail. Its expression was increased in the presence of cellobiose, and decreased in the presence of glucose. A novel GntR-type transcriptional regulator (which we here denote as BguR) was shown to act as a transcriptional repressor of the bgu operon and its repressive effect was relieved in the presence of cellobiose. BguR-dependent repression was demonstrated to be mediated by a 20-bp DNA operator site (5M-bM-^@M-^Y-AAAAATGTCTAGACAAATTT-3M-bM-^@M-^Y) present in PbguA as verified by promoter truncation experiments. In conclusion, we have identified a new cellobiose-responsive PTS operon, together with its transcriptional regulator in S. pneumoniae. One condition design, comparison of two strains including a dye swap
2013-02-20 | E-GEOD-43342 | biostudies-arrayexpress
Project description:Comparison of the Streptococcus pneumoniae D39 celR mutant compared to D39 wild type in M17 medium+ 0.5 % (w/v) Cellobiose (CM17) The human pathogen Streptococcus pneumoniae harbors many genes encoding phosphotransferase systems (PTSs) and sugar ABC (ATP-binding cassette) transporters, including systems for the utilization of the ?-glucoside sugar cellobiose. In this study, we show that the transcriptional regulator CelR, which has previously been found to be important for pneumococcal virulence, activates the expression of the cellobiose-utilization gene cluster (cel locus) of S. pneumoniae. Expression directed by the two promoters present in the cel locus was increased in the presence of cellobiose as a sole carbon source in the medium, while expression decreased in the presence of glucose in the medium. Furthermore, we have predicted a 22-bp putative CelR regulatory site (5?-YTTTCCWTAWCAWTWAGGAAAA-3?) in the promoters of celA and celB and in silico analysis showed that it is highly conserved in other pathogenic streptococci as well. Promoter truncations of celA and celB, where the half or full CelR regulatory site was deleted, confirmed that the CelR binding site in PcelA and PcelB is functional. Transcriptome studies with the celR mutant and in silico prediction of the CelR regulatory site in the entire D39 genome sequence show that the cel locus is the only cluster of genes under the direct control of CelR. Therefore, CelR is a regulator dedicated to the cellobiose-dependent transcriptional activation of the cel locus. One condition design comparision of two strains including a dye swap
2011-07-24 | E-GEOD-30891 | biostudies-arrayexpress
Project description:PrfA activity was studied in L. monocytogenes strain EGD and in an isogenic prfA deletion mutant (EGDΔprfA) carrying multiple copies of the wild-type prfA or the mutant prfA* gene (strains EGDΔprfApPrfA and EGDΔprfApPrfA*) after growth in brain heart infusion (BHI), Luria-Bertani broth (LB) or a defined minimal medium (MM) supplemented either with one of the three PTS-carbohydrates, glucose, mannose and cellobiose, or the non-PTS carbon source glycerol. Low PrfA activity was observed in the wild-type EGD strain in BHI and LB with either of these carbon sources, while PrfA activity was high in minimal medium in presence of glycerol but significantly reduced in presence of cellobiose. The strains expressing the prfA and prfA* gene under the prfA promoters, P1 and P2, produced equally large amounts of PrfA protein and high PrfA activity was observed in strain EGDΔprfApPrfA* under all growth conditions. In contrast, high PrfA activity in strain EGDΔprfApPrfA was only observed when this strain was cultured in BHI but not in LB or MM (in presence of either carbon source). A ptsH mutant (lacking a functional HPr) was able to grow in BHI suggesting that growth of L. monocytogenes in this culture medium is supported by carbon sources whose uptake and metabolism are independent of the PTS pathway. However, this mutant was unable to grow in LB and MM regardless which of the four carbon sources was added, suggesting that uptake of the used carbohydrates and the catabolism of glycerol depend fully on the functional common PTS pathway. Furthermore, the growth rates of L. monocytogenes are strongly reduced in presence of large amounts of PrfA protein when growing MM but less in LB and only slightly in BHI. The expression profiles of the genes encoding PTS permeases were determined in the three strains under various growth conditions. The data suggest that PrfA activity correlates with the expression level and the phosphorylation state of specific PTS permeases. This SuperSeries is composed of the SubSeries listed below.
2008-12-01 | GSE12151 | GEO
Project description:Transcriptome comparison of the Streptococcus pneumoniae strain D39 grown in the presence of either lactose or galactose with that of the strain grown in the presence of glucose, revealed the elevated expression of various genes and operons, including the lac gene cluster that is organized into two operons i.e. lac operon-I (lacABCD) and lac operon-II (lacTFEG). Deletion of the DeoR family transcriptional regulator lacR that is present downstream of the lac gene cluster, revealed elevated expression of lac operon-I, even in the absence of lactose. This suggests a function of LacR as a transcriptional repressor of lac operon-I that encodes enzymes involved in the Tagatose-6-P pathway in the absence of lactose or galactose. Deletion of lacR did not affect the expression of lac operon-II that encodes for a lactose-specific PTS. This finding was further confirmed by ?-galactosidase assays with PlacA-lacZ and PlacT-lacZ in the presence of either lactose or glucose as a sole carbon source in the medium. This suggests the presence of another transcriptional regulator in the regulation of lac operon-II, which could be the BglG-family transcriptional antiterminator LacT. We demonstrate the role of LacT as a transcriptional activator of lac operon-II in the presence of lactose and CcpA-independent regulation of the lac gene cluster in S. pneumoniae. This SuperSeries is composed of the SubSeries listed below.
2014-06-20 | GSE58184 | GEO
Project description:Abstract: Transcriptome comparison of the Streptococcus pneumoniae strain D39 grown in the presence of either lactose or galactose with that of the strain grown in the presence of glucose, revealed the elevated expression of various genes and operons, including the lac gene cluster that is organized into two operons i.e. lac operon-I (lacABCD) and lac operon-II (lacTFEG). Deletion of the DeoR family transcriptional regulator lacR that is present downstream of the lac gene cluster, revealed elevated expression of lac operon-I, even in the absence of lactose. This suggests a function of LacR as a transcriptional repressor of lac operon-I that encodes enzymes involved in the Tagatose-6-P pathway in the absence of lactose or galactose. Deletion of lacR did not affect the expression of lac operon-II that encodes for a lactose-specific PTS. This finding was further confirmed by ?-galactosidase assays with PlacA-lacZ and PlacT-lacZ in the presence of either lactose or glucose as a sole carbon source in the medium. This suggests the presence of another transcriptional regulator in the regulation of lac operon-II, which could be the BglG-family transcriptional antiterminator LacT. We demonstrate the role of LacT as a transcriptional activator of lac operon-II in the presence of lactose and CcpA-independent regulation of the lac gene cluster in S. pneumoniae. This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2014-06-20 | E-GEOD-58184 | biostudies-arrayexpress
Project description:PrfA activity was studied in L. monocytogenes strain EGD and in an isogenic prfA deletion mutant (EGDΔprfA) carrying multiple copies of the wild-type prfA or the mutant prfA* gene (strains EGDΔprfApPrfA and EGDΔprfApPrfA*) after growth in brain heart infusion (BHI), Luria-Bertani broth (LB) or a defined minimal medium (MM) supplemented either with one of the three PTS-carbohydrates, glucose, mannose and cellobiose, or the non-PTS carbon source glycerol. Low PrfA activity was observed in the wild-type EGD strain in BHI and LB with either of these carbon sources, while PrfA activity was high in minimal medium in presence of glycerol but significantly reduced in presence of cellobiose. The strains expressing the prfA and prfA* gene under the prfA promoters, P1 and P2, produced equally large amounts of PrfA protein and high PrfA activity was observed in strain EGDΔprfApPrfA* under all growth conditions. In contrast, high PrfA activity in strain EGDΔprfApPrfA was only observed when this strain was cultured in BHI but not in LB or MM (in presence of either carbon source). A ptsH mutant (lacking a functional HPr) was able to grow in BHI suggesting that growth of L. monocytogenes in this culture medium is supported by carbon sources whose uptake and metabolism are independent of the PTS pathway. However, this mutant was unable to grow in LB and MM regardless which of the four carbon sources was added, suggesting that uptake of the used carbohydrates and the catabolism of glycerol depend fully on the functional common PTS pathway. Furthermore, the growth rates of L. monocytogenes are strongly reduced in presence of large amounts of PrfA protein when growing MM but less in LB and only slightly in BHI. The expression profiles of the genes encoding PTS permeases were determined in the three strains under various growth conditions. The data suggest that PrfA activity correlates with the expression level and the phosphorylation state of specific PTS permeases. This SuperSeries is composed of the following subset Series: GSE12143: Listeria monocytogenes EGD after growth BHI vs. LB vs. MM GSE12145: Listeria monocytogenes EGDΔprfApPrfA and EGDΔprfApPrfA* compared to the wild type strain EGD GSE12146: Listeria monocytogenes EGD and EGD-e
2008-11-30 | E-GEOD-12151 | biostudies-arrayexpress
Project description:In this study, we have explored the impact of ascorbic acid on the transcriptome of Streptococcus pneumoniae D39. The expression of several genes and operons, including the ula operon (which has been previously shown to be involved in ascorbic acid utilization), the AdcR regulon (which has been previously shown to be involved in zinc transport and virulence) and a PTS operon (which we denote here as ula2 operon) were altered in the presence of ascorbic acid. The ula2 operon consists of five genes, including the transcriptional activator ulaR2. Our M-NM-2-galactosidase assay data and transcriptome comparison of the ulaR2 mutant with the wild-type demonstrated that the transcriptional activator UlaR2 in the presence of ascorbic acid activates the expression of the ula2 operon. We further predict a 16-bp regulatory site (5M-bM-^@M-^Y-ATATTGTGCTCAAATA-3M-bM-^@M-^Y) for UlaR2 binding in the Pula2. Furthermore, we have explored the effect of ascorbic acid on the expression of the AdcR regulon. Our ICP-MS analysis showed that addition of ascorbic acid to the medium causes zinc starvation in the cell that leads to the activation of the AdcR regulon. Comparison of the Streptococcus pneumoniae D39 compared to D39 wild type in M17 medium+ 10mM ascorbic acid (AM17) Two conditions design comparision of one strain including a dye swap
2015-01-21 | E-GEOD-64105 | biostudies-arrayexpress
Project description:In this study, we have explored the impact of ascorbic acid on the transcriptome of Streptococcus pneumoniae D39. The expression of several genes and operons, including the ula operon (which has been previously shown to be involved in ascorbic acid utilization), the AdcR regulon (which has been previously shown to be involved in zinc transport and virulence) and a PTS operon (which we denote here as ula2 operon) were altered in the presence of ascorbic acid. The ula2 operon consists of five genes, including the transcriptional activator ulaR2. Our M-NM-2-galactosidase assay data and transcriptome comparison of the ulaR2 mutant with the wild-type demonstrated that the transcriptional activator UlaR2 in the presence of ascorbic acid activates the expression of the ula2 operon. We further predict a 16-bp regulatory site (5M-bM-^@M-^Y-ATATTGTGCTCAAATA-3M-bM-^@M-^Y) for UlaR2 binding in the Pula2. Furthermore, we have explored the effect of ascorbic acid on the expression of the AdcR regulon. Our ICP-MS analysis showed that addition of ascorbic acid to the medium causes zinc starvation in the cell that leads to the activation of the AdcR regulon. Comparison of the Streptococcus pneumoniae D39 ulaR2 mutant compared to D39 wild type in M17 medium+ 10mM ascorbic acid (AM17) One condition design comparision of two strains including a dye swap
2015-01-21 | E-GEOD-64106 | biostudies-arrayexpress