Whole-transcriptome response of the cyanobacterium Synechocystis to hexan-1-ol
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ABSTRACT:
ORGANISM(S): Synechocystis sp. PCC 6803
PROVIDER: GSE118423 | GEO | 2018/08/11
REPOSITORIES: GEO
Similar Datasets
Project description:Whole-transcriptome response of the cyanobacterium Synechocystis to hexan-1-ol
| PRJNA485521 | ENA
Project description:Cyanobacteria, photoautotrophic prokaryotes, contribute significantly to the global photosynthesis and require large amounts of the essential micronutrient iron in order to maintain their Fe-rich photosynthetic apparatus. Here we use the model organism Synechocystis sp. PCC 6803 (later referred to Synechocystis) in both, standard and iron stress conditions, to study transcription and post-transcription regulation in iron deprivation. Although iron is one of the most abundant metals on earth, it is not soluble under aerobic conditions. Thus Synechocystis had to find ways to overcome iron deficiency. At the same time, however, free intracellular iron needs to be kept at permissive levels, as it becomes toxic under aerobic conditions by producing reactive oxygen species. For these reasons, complex regulatory networks have evolved to tightly control intracellular iron concentrations, ensuring its essential function yet avoiding cellular damage (Pierre Cornelis et al). In a previous study, we investigated iron deprivation in Synechocystis using customised amplification library for the analysis of global gene expression in the unicellular cyanobacterium (Hernández-Prieto et al, 2012; Georg et al, 2017),(Georg et al, 2017) but it is still little known about RNA stability in this organism. We now extend this study through a transcriptome wide half-life analysis in Synechocystis grown under standard and iron-limiting conditions using oligonucleotide microarrays that detect both protein-coding and non-coding transcripts (ncRNA). We used the antibiotic Rifampicin to stop the transcription. Samples were taken at time points 0 min (before the addition of rifampicin) and in a time series of 2 min, 4 min, 8 min, 16 min, 32 min and 64 min after its addition.
2022-07-30 | GSE209879 | GEO
Project description:The response of the model cyanobacterium Synechocystis sp. PCC6803 towards light and carbon limitation was systematically probed. To this end, Synechocystis sp. PCC6803 was cultivated in a photo-bioreactor driven in turbidostat-mode. The turbidostat is a continuous cultivation that enabled cells to adapt to a constant environment, leading to a stable and 'optimal' proteome for the respective condition. The major dataset in this project consisted of 5 different 'concentrations' for light and CO2. Changes in the proteome were determined using using liquid chromatography/mass spectrometry and it was found that carbon and light limitation induced gradual but broad responses in gene expression. With decreasing substrate concentration (increasing limitation) a decrease in growth rate and a gradually more severe response in the proteome was visible.
2018-09-12 | PXD009582 | Pride
Project description:Photoautotrophic cyanobacteria assimilate the greenhouse gas carbon dioxide as their sole carbon source for producing useful bioproducts. However, harvesting the cells from their liquid media is a major bottleneck in the process. Thus, an easy-to-harvest method, such as auto-flocculation, is desirable. Here, we found that cyanobacterium Synechocystis sp. PCC 6803 co-flocculated with a natural fungal contamination in the presence of the antibiotic erythromycin (EM) but not without EM. The fungi in the co-flocculated biomass were isolated and found to consist of five species with the filamentous Purpureocillium lilacinum and Aspergillus protuberus making up 71% of the overall fungal population. The optimal co-cultivation for flocculation was an initial 5 mg (fresh weight) of fungi, an initial cell density of Synechocystis of 0.2 OD730, 10 µM EM, and 14 days of cultivation in 100 mL of BG11 medium with no organic compound. This yielded 248 ± 28 mg/L of the Synechocystis-fungi flocculated biomass from 560 ± 35 mg/L of total biomass, a 44 ± 2 % biomass flocculation efficiency. Furthermore, the EM treated Synechocystis cells in the Synechocystis-fungi flocculate had a normal cell color and morphology, while those in the axenic suspension exhibited strong chlorosis. Thus, the occurrence of the Synechocystis-fungi flocculation was mediated by EM, and the co-flocculation with the fungi helped Synechocystis to alleviate the negative effect of EM. Transcriptomic analysis of suspended and flocculated (with the fungi) Synechocystis cells suggested that the EM-mediated co-flocculation was a result of down-regulation of the minor pilin genes and up-regulation of several genes including the chaperone gene for pilin regulation, the S-layer protein genes, the exopolysaccharide-polymerization gene, and the genes for signaling proteins involved in cell attachment and abiotic-stress responses. The EM treatment may be applied in the co-culture between other cyanobacteria and fungi to mediate cell bio-flocculation.
2024-05-01 | GSE256452 | GEO
Project description:Photoautotrophic cyanobacteria assimilate the greenhouse gas carbon dioxide as their sole carbon source for producing useful bioproducts. However, harvesting the cells from their liquid media is a major bottleneck in the process. Thus, an easy-to-harvest method, such as auto-flocculation, is desirable. Here, we found that cyanobacterium Synechocystis sp. PCC 6803 co-flocculated with a natural fungal contamination in the presence of the antibiotic erythromycin (EM) but not without EM. The fungi in the co-flocculated biomass were isolated and found to consist of five species with the filamentous Purpureocillium lilacinum and Aspergillus protuberus making up 71% of the overall fungal population. The optimal co-cultivation for flocculation was an initial 5 mg (fresh weight) of fungi, an initial cell density of Synechocystis of 0.2 OD730, 10 µM EM, and 14 days of cultivation in 100 mL of BG11 medium with no organic compound. This yielded 248 ± 28 mg/L of the Synechocystis-fungi flocculated biomass from 560 ± 35 mg/L of total biomass, a 44 ± 2 % biomass flocculation efficiency. Furthermore, the EM treated Synechocystis cells in the Synechocystis-fungi flocculate had a normal cell color and morphology, while those in the axenic suspension exhibited strong chlorosis. Thus, the occurrence of the Synechocystis-fungi flocculation was mediated by EM, and the co-flocculation with the fungi helped Synechocystis to alleviate the negative effect of EM. Transcriptomic analysis of suspended and flocculated (with the fungi) Synechocystis cells suggested that the EM-mediated co-flocculation was a result of down-regulation of the minor pilin genes and up-regulation of several genes including the chaperone gene for pilin regulation, the S-layer protein genes, the exopolysaccharide-polymerization gene, and the genes for signaling proteins involved in cell attachment and abiotic-stress responses. The EM treatment may be applied in the co-culture between other cyanobacteria and fungi to mediate cell bio-flocculation.
2024-05-01 | GSE256451 | GEO
Project description:Gene expression changes were followed in cultures of the cyanobacterium Synechocystis sp. PCC 6803 substrain GT-T cultivated at ambient air or supplemented with 3% CO2. The acclimation to different CO2 concentrations is crucial for photoautotrophic organisms living in aquatic environments such as cyanobacteria. Samples were taken before and 1 h and 24 h after transfer to the3 % CO2 environment. The analyzed strains were wild type, a deletion mutant of gene ssl2982/rpoZ (ΔrpoZ) and two suppressor strains (R1, ΔrpoZ-S1 and R2, ΔrpoZ-S2). In cyanobacteria, elevated CO2 is known to down-regulate carbon concentrating mechanisms and accelerate photosynthesis and growth, but mechanism(s) of carbon signalling remains only poorly understood. Here we reveal a novel signalling cascade connecting the amount of CO2 and growth in the model cyanobacterium Synechocystis sp. PCC 6803. Deletion of the small ω subunit of the RNA polymerase (RNAP) in the ΔrpoZ strain prevents normal high-CO2-induced up-regulation of numerous photosynthetic genes, and low expression of peptidoglycan synthesis genes induced lysis of dividing ΔrpoZ cells in high CO2. Spontaneously raised secondary mutations in the ssr1600 gene rescued the high-CO2-sensitive phenotype of the ΔrpoZ strain. Biochemical analyses showed that the ssr1600 gene encodes an anti-σ factor antagonist of group 2 σ factor SigC, and 3D structural modelling suggest that Slr1861 functions as an anti-SigC factor. In ΔrpoZ, excess formation of RNAP-SigC lead to high CO2 sensitive phenotype, whereas the drastically reduced Ssr1600 content in the suppressor mutants reduce the formation of the RNAP-SigC holoenzyme to the similar level as in the control strain, allowing almost normal transcriptome and growth of suppressor lines in high CO2. We propose that the SigC σ factor, the anti-SigC factor Slr1861 and the anti-SigC antagonist Ssr1600 forms a growth regulating signalling cascade in cyanobacteria.
2025-05-01 | GSE233434 | GEO
Project description:The production of biofuels in photosynthetic microalgae and cyanobacteria is considered a promising alternative to the generation of fuels from fossil resources. However, to be economically competitive, producer strains need to be established that synthesize the targeted product at high yield and over a long time. Engineering cyanobacteria to forced fuel producers should considerably interfere with overall cell homeostasis, which in turn might counteract productivity and sustainability of the process. Therefore, in-depth characterization of the cellular response upon long-term production is of high interest for the targeted improvement of a desired strain. Here we report the results of a monitoring experiment, in which the transcriptome-wide response to continuous ethanol production in the unicellular model cyanobacterium Synechocystis sp. PCC6803 was examined using high resolution microarrays. In two independent experiments, ethanol production rates of 0.0338% (v/v) EtOH d-1 M-BM-1 0.002 and 0.0303% (v/v) d-1 M-BM-1 0.002 were obtained over 18 consecutive days, measuring biological triplicates in fully automated photobioreactors. Ethanol production caused a significant (~40%) delay in biomass accumulation in the producer strains and the development of a bleaching phenotype. Absorption spectroscopy indicated in particular a down-regulation of light harvesting capacity. Microarray analyses performed at day 4, 7, 11 and 18 of the experiment revealed only three mRNAs with a strongly modified accumulation level throughout the course of the experiment. In addition to the overexpressed adhA (slr1192) gene, this was an about 4 fold reduction in cpcB (sll1577) and an about 3 to 6 fold increase in rps8 (sll1809) mRNA levels. Much weaker modifications of expression level or modifications restricted to day 18 of the experiment were observed for genes involved in carbon assimilation (Ribulose bisphosphate carboxylase and Glutamate decarboxylase). Molecular analysis of the reduced cpcB levels revealed a post-transcriptional operon discoordination in the cpcBA operon leaving a truncated mRNA cpcA* likely not competent for translation. Moreover, Western blots and zinc-enhanced bilin fluorescence blots confirmed a severe reduction in the amounts of both phycocyanin subunits, explaining the cause of the bleaching phenotype. We conclude that the changes in gene expression upon induction of long term ethanol production in Synechocystis sp. PCC6803 are highly specific. in particular we did not observe a comprehensive stress response contributing to a complex phenotype as might have been expected. Gene expression of Synechocystis sp. PCC 6803 WT (#621) and the isogenic ethanol producing strain #309 was monitored at 4, 7, 11 and 18 days after induction of ethanol production by copper depletion. Each condition was sampled in biological duplicates
2013-08-06 | E-GEOD-49552 | biostudies-arrayexpress
Project description:Regulation of gene expression is a sophisticated process leading to the activation or suppression of genes due to adaptation to environmental stimuli. The membrane-embedded FtsH proteases conserved in bacteria, chloroplasts and mitochondria, are involved in such regulation. The genome of the cyanobacterium Synechocystis sp. PCC 6803 encodes four FtsH homologues FtsH1-4, functioning in the form of oligomeric complexes. Homologue FtsH3 is bound in two hetero-oligomeric complexes, FtsH1/FstH3 and/or FtsH2/FtsH3, respectively. Previous data showed that the FtsH1/FtsH3 complex is involved in the acclimation of cells to iron deficiency by controlling the availability of the transcriptional regulator Fur (Sll0567). To gain more comprehensive insight into the physiological role of FtsH hetero-complexes, we carried out genome-wide expression profiling of a mutant conditionally depleted in FtsH3, grown under nutrient sufficiency and iron depletion. Our results show, that besides Fur, also the SufR and Pho regulons belong to the set of genes controlled by FtsH. Moreover, by combining the transcriptome data with in silico prediction we identified novel targets of Fur in Synechocystis PCC 6803. Fur tends to evoke mostly repression, but also appears to activate some target genes. We monitored the global gene expression in a conditional Synechocystis PCC6083 ftsH knockdown strain (FtsHdown) (Boehm et al., 2012) and a control strain (WT) at standard conditions and at iron depletion. The presence of ammonia to induced the conditional knockdown. Each sample was done in biological replicates.
2016-06-14 | E-GEOD-83303 | biostudies-arrayexpress
Project description:The model cyanobacterium Synechocystis sp. PCC 6803 was used for a systematic survey of differential expression with a focus on antisense (as)RNAs and non-coding (nc)RNAs. A microarray was constucted with on average 5 probes for each transcript known thus far, including ncRNAs and asRNAs. The resulting 20,431 individual probes are duplicated on the array (Agilent 4x44k custom array) representing a technical replicate. Hybridization of this array with total RNA isolated from cultures raised under different growth conditions identified transcripts from intergenic spacers and in antisense orientation to known genes (natural cis-asRNAs) with differential expression compared to control hybridizations. This shows the involvement of such transcripts in the regulation of adaptation to various stresses. 12 RNA hybridizations (1 control & 3 stress conditions, 3 times each)
2010-05-18 | E-GEOD-16162 | biostudies-arrayexpress
Project description:The model cyanobacterium Synechocystis sp. PCC 6803 was used for a systematic survey of differential expression with a focus on antisense (as)RNAs and non-coding (nc)RNAs. A microarray was constucted with on average 5 probes for each transcript known thus far, including ncRNAs and asRNAs. The resulting 20,431 individual probes are duplicated on the array (Agilent 4x44k custom array) representing a technical replicate. Hybridization of this array with total RNA isolated from cultures raised under different growth conditions identified transcripts from intergenic spacers and in antisense orientation to known genes (natural cis-asRNAs) with differential expression compared to control hybridizations. This shows the involvement of such transcripts in the regulation of adaptation to various stresses.
2009-05-20 | GSE16162 | GEO