Analysis of Thermosynechococcus elongatus BP1 response to co-cultivation with Meiothermus ruber strain A
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ABSTRACT:
ORGANISM(S): Thermosynechococcus vestitus BP-1
PROVIDER: GSE94125 | GEO | 2017/01/27
SECONDARY ACCESSION(S): PRJNA368993
REPOSITORIES: GEO
Similar Datasets
Project description:The transcriptional response of the cyanobacteria T. elongatus to co-cultiavation with a heterotrophic partner M. ruber was examined under three varying light levels and three varying oxygen levels.
2017-01-20 | GSE93859 | GEO
Project description:<p><strong>BACKGROUND:</strong> Converting carbon dioxide (CO2) into value-added chemicals using engineered cyanobacteria is a promising strategy to tackle the global warming and energy shortage issues. However, most cyanobacteria are autotrophic and use CO2 as a sole carbon source, which makes it hard to compete with heterotrophic hosts in either growth or productivity. One strategy to overcome this bottleneck is to introduce sugar utilization pathways to enable photomixotrophic growth with CO2 and sugar (e.g., glucose and xylose). Advances in engineering mixotrophic cyanobacteria have been obtained, while a systematic interrogation of these engineered strains is missing. This work aimed to fill the gap at omics level.</p><p><strong>RESULTS:</strong> We first constructed two engineered <em>Synechococcus elongatus</em> YQ2-gal and YQ3-xyl capable of utilizing glucose and xylose, respectively. To investigate the metabolic mechanism, transcriptomic and metabolomic analysis were then performed in the engineered photomixotrophic strains YQ2-gal and YQ3-xyl. Transcriptome and metabolome of wild-type <em>S. elongatus</em> were set as baselines. Increased abundance of metabolites in glycolysis or pentose phosphate pathway indicated that efficient sugar utilization significantly enhanced carbon flux in <em>S. elongatus</em> as expected. However, carbon flux was redirected in strain YQ2-gal as more flowed into fatty acids biosynthesis but less into amino acids. In strain YQ3-xyl, more carbon flux was directed into synthesis of sucrose, glucosamine and acetaldehyde, while less into fatty acids and amino acids. Moreover, photosynthesis and bicarbonate transport could be affected by upregulated genes, while nitrogen transport and assimilation were regulated by less transcript abundance of related genes in strain YQ3-xyl with utilization of xylose.</p><p><strong>CONCLUSIONS:</strong> Our work identified metabolic mechanism in engineered <em>S. elongatus</em> during photomixotrophic growth, where regulations of fatty acids metabolism, photosynthesis, bicarbonate transport, nitrogen assimilation and transport are dependent on different sugar utilization. Since photomixotrophic cyanobacteria is regarded as a promising cell factory for bioproduction, this comprehensive understanding of metabolic mechanism of engineered <em>S. elongatus</em> during photomixotrophic growth would shed light on the engineering of more efficient and controllable bioproduction systems based on this potential chassis.</p>
2022-03-21 | MTBLS2825 | MetaboLights
Project description:Biological CO2 mitigation by photosynthetic microorganisms has emerged as a promising approach for generating biomass-based energy during the course of CO2 fixation. Additionally, cyanobacteria-based biofuels have also garnered immense attention lately because of the depleting fossil fuel reserves and the growing energy demands. Synechococcus elongatus PCC 11801, a fast-growing, high CO2 tolerant, novel isolate of cyanobacteria, is an interesting candidate for metabolic engineering applications. Since under laboratory conditions, it exhibited a high level of tolerance to different environmental stresses (CO2, light, temperature, salts and butanol), it seemed like an encouraging prospect for the production of fuels and other industrially relevant chemicals. This is the first-ever functional global proteomics investigation of Synechococcus elongatus PCC 11801 isolate grown at elevated CO2 levels using high-throughput iTRAQ approach. Three independent biological replicates were analyzed and a total of 861 proteins were identified, out of which 492 proteins were found to be present in all the three replicates. Of these, 248 proteins showing the same trend across the three replicates (≥1.5 fold up-regulation or ≤0.66 fold down-regulation) were chosen for pathway analysis. The metabolic responses were marked with a down-regulation of inorganic carbon transporters alongside an induction of nitrogen transport and absorption proteins in order to uphold the apposite carbon-nitrogen equilibrium. Further acclimation progression exposed an increased expression of proteins taking part in photosynthesis and generation of light harvesting pigments such as chlorophyll. Similarly, a downshift of proteins involved in photoprotection and defense against ROS (reactive oxygen species) was observed. Another principal discovery was the perturbation in expression of proteins belonging to central metabolic pathways like glycolysis, TCA cycle, pentose phosphate pathway as a coping mechanism to high CO2 stress. Further, validation studies were carried out using MRM assays and western blotting of key altered proteins.
2019-04-23 | PXD011485 | Pride
Project description:Top down mass spectrometry analysis of Synechococcus elongatus UTEX2973 cyanobacteria under nitrogen starvation over time course of 4 hours. A number of phycobiliproteins covalently linked to phycocyanobilin pigments were detected as intact forms. Some of them showed partial degradation of the protein backbones or the pigment structures. NblA, a small protein that is believed to play a key role in phycobilisome degradation was shown to be highly correlated to nitrogen starvation based on its remarkable change of protein abundance.
2019-08-27 | PXD014590 | Pride
Project description:An excess of reactive oxygen species (ROS) can cause severe oxidative damage to cellular components in photosynthetic cells. Antioxidant systems, such as the ascorbate-glutathione cycle, regulate redox status in cells to guard against such damage. Dehydroascorbate reductase (DHAR, EC 1.8.5.1) catalyzes the glutathione-dependent reduction of oxidized ascorbate (dehydroascorbate) and contains a redox active site and glutathione binding-site. The DHAR gene is important in biological and abiotic stress responses involving reduction of the oxidative damage caused by ROS. In this study, a transgenic microalgae (TA) strain was constructed by cloning the Oryza sativa L. japonica DHAR (OsDHAR) gene controlled by an isopropyl β-D-1-thiogalactopyranoside (IPTG)-inducible promoter (Ptrc) into the Synechococcus elongatus PCC 7942 strain of cyanobacteria to study the functional activities of OsDHAR under oxidative stress caused by hydrogen peroxide exposure. OsDHAR expression increased the growth of S. elongatus PCC 7942 under oxidative stress by reducing the levels of hydroperoxides and malondialdehyde (MDA) and mitigating the loss of chlorophyll. DHAR and glutathione S-transferase activity were higher than in the wild-type (WT) strain. Additionally, overexpression of OsDHAR in S. elongatus PCC 7942 greatly increased the glutathione (GSH)/glutathione disulfide (GSSG) ratio compared to ascorbic acid (AsA)/dehydroascorbate (DHA) ratio in the presence or absence of hydrogen peroxide. These results strongly suggest that DHAR attenuates deleterious oxidative effects via the glutathione (GSH)-dependent antioxidant system in cyanobacterial cells. The expression of heterologous OsDHAR in S. elongatus PCC 7942 protected cells from oxidative damage through a GSH-dependent antioxidant system via GSH-dependent reactions at the redox active site and GSH binding site residues during oxidative stress.
2019-11-25 | GSE140121 | GEO
Project description:Zinc oxide (ZnO) nanoparticles are commonly used in sunscreens for their UV-filtering properties. Their growing use can lead to their release into ecosystems, raising question about their toxicity. Effects of these engineered nanomaterials (ENMs) on cyanobacteria, which are important primary producers involved in many biogeochemical cycles, are unknown. In this study, we investigated by several complementary approaches the toxicological effects of two marketed ZnO-ENMs (coated and uncoated) on the model cyanobacteria Synechococcus elongatus PCC 7942. It was shown that despite the rapid adsorption of ENMs on cell surface, toxicity is mainly due to labile Zn released by ENMs. Zn dissipates cell membrane potential necessary for both photosynthesis and respiration, and induces oxidative stress leading to lipid peroxidation and DNA damages. It leads to global downregulation of photosystems, oxidative phosphorylation, and transcription/translation machineries. This also translates into significant decrease of intracellular ATP content and cell growth inhibition. However, there is no major loss of pigments and even rather an increase in exposed cells compared to controls. A proposed way to reduce the environmental impact of Zn would be the improvement of the coating stability to prevent solubility of ZnO-ENMs.
2019-06-05 | GSE102914 | GEO