Regulation of uptake hydrogenase and effects of hydrogen utilization on gene expression in Rhodopseudomonas palustris
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ABSTRACT:
ORGANISM(S): Rhodopseudomonas palustris
PROVIDER: GSE4320 | GEO | 2006/11/03
SECONDARY ACCESSION(S): PRJNA94739
REPOSITORIES: GEO
Similar Datasets
Project description:To address the question of how photosynthetic bacterium Rhodopseudomonas palustris differentially regulates gene expression of three nitrogenase isozymes (Mo, V, and Fe nitrogenases), we constructed Mo strain (Mo nitrogenase only strain), V strain (V nitrogenase only strain), and Fe strain (Fe nitrogenase only strain), and analyzed the whole genome transcriptome profiles of each mutant and wild-type cells grown under nitrogen-fixing conditions. Keywords: Genetic modification
2005-11-10 | GSE3030 | GEO
Project description:Rhodopseudomonas palustris is a purple, facultatively phototrophic bacterium that uses hydrogen gas as an electron donor for carbon dioxide fixation during photoautotrophic growth or for ammonia synthesis during nitrogen fixation. It also uses hydrogen as an electron supplement to enable the complete assimilation of oxidized carbon compounds, such as malate, into cell material during photoheterotrophic growth. The R. palustris genome predicts a membrane-bound nickel-iron uptake hydrogenase and several regulatory proteins to control hydrogenase synthesis. There is also a novel sensor kinase gene (RPA0981) directly adjacent to the hydrogenase gene cluster. Here we show that the R. palustris regulatory sensor hydrogenase HupUV acts in conjunction with the sensor kinase-response regulator protein pair HoxJ-HoxA to activate hydrogenase expression in response to hydrogen gas. Transcriptome analysis indicated that the HupUV-HoxJA regulatory system also controls the expression of genes encoding a predicted dicarboxylic acid transport system, a putative formate transporter, and a glutamine synthetase. RPA0981 had a small effect in repressing hydrogenase synthesis. We also determined that the two-component system RegS-RegR repressed expression of the uptake hydrogenase, probably in response to changes in intracellular redox status. Transcriptome analysis indicated that about 30 genes were differentially expressed in R. palustris cells that utilized hydrogen when growing photoheterotrophically on malate under nitrogen-fixing conditions compared to a mutant strain that lacked uptake hydrogenase. From this it appears that the recycling of reductant in the form of hydrogen does not have extensive nonspecific effects on gene expression in R. palustris.
| S-EPMC1595397 | biostudies-literature
Project description:Characterization of post-translational modification of nitrogenase in Rhodopseudomonas palustris strains that produce hydrogen gas constitutively. To characterize the effect of yeast extract as nitrogen source on gene expression under nitrogen fixing conditions, expression profiles of wild-type cells grown on either NF plus yeast extract and succinate and PM plus ammonium sulfate and succinate were compared using Affymetrix GeneChip. Using NF plus yeast extract and succinate media, transcriptome profiles of various mutants and wild-type cells were compared using glass spotted microarrays.
2012-03-15 | E-GEOD-32292 | biostudies-arrayexpress
Project description:Transcriptome analysis of hopanoid biosynthetic mutant of Rhodopseudomonas palustris TIE-1
| PRJNA335757 | ENA
Project description:To address the question of how photosynthetic bacterium Rhodopseudomonas palustris differentially regulates gene expression of three nitrogenase isozymes (Mo, V, and Fe nitrogenases), we constructed Mo strain (Mo nitrogenase only strain), V strain (V nitrogenase only strain), and Fe strain (Fe nitrogenase only strain), and analyzed the whole genome transcriptome profiles of each mutant and wild-type cells grown under nitrogen-fixing conditions. RNA was isolated from various Rhodopseudomonas palustris strains that were grown to the mid-logarithmic phase of growth. Fluorescently labeled cDNA was prepared by direct incorporation of either Cy3-dCTP or Cy5-dCTP during a first-strand reverse transcription reaction. The hybridization mixtures containing the two labeled cDNA samples to be compared were applied to microarray slides that had been covered with Lifterslips (Erie Scientific Company, Portsmouth, NH). The slides were assembled with hybridization chambers (Corning, Corning, NY) and submerged in a 65ºC water bath. After 14-16 h of hybridization, the slides were washed and scanned with a ScanArray 4000XL scanner (PerkinElmer, Boston, MA). Images (Cy3 and Cy5) were captured as TIFF files and were analyzed with the image processing software ImaGene version 5.6 (BioDiscovery, Inc., El Segundo, CA). The software package lcDNA was used for data normalization and assessment of the statistical confidence intervals of gene expression. Duplicate calibration experiments and three comparative experiments using RNA from three separately grown cultures (three biological replicates) with duplicate slides for each (10 slides in total) were used to generate each data set.
2010-06-30 | E-GEOD-3030 | biostudies-arrayexpress
Project description:To understand the role of pentacyclic triterpenoids, we used whole genome microarray expression profiling of wild type and hopanoid deficient mutant. Hopanoid deficiency may leads to weakened structural integrity of cell membrane and may affect the other structures within or spanning cell envelope resulting in impaired lipid ordering which is linked to permeability, fluidity, permeability barrier, ion conductivity, cell potential, cell signalling and lateral segregation. Hopanoids are involved in antibiotic resistance and tolerance to stress, but the precise understanding is lacking. Understanding the role of hopanoids in shaping membrane properties would provide an important step towards bridging this gap.
2017-04-30 | GSE84950 | GEO
Project description:Extracellular electron uptake (EEU) is the ability of microbes to take up electrons from solid-phase conductive substances such as metal oxides. EEU is performed by prevalent phototrophic bacterial genera, but the electron transfer pathways and the physiological electron sinks are poorly understood. Here we show that electrons enter the photosynthetic electron transport chain during EEU in the phototrophic bacterium Rhodopseudomonas palustris TIE-1. Cathodic electron flow is also correlated with a highly reducing intracellular redox environment. We show that reducing equivalents are used for carbon dioxide (CO2) fixation, which is the primary electron sink. Deletion of the genes encoding ruBisCO (the CO2-fixing enzyme of the Calvin-Benson-Bassham cycle) leads to a 90% reduction in EEU. This work shows that phototrophs can directly use solid-phase conductive substances for electron transfer, energy transduction, and CO2 fixation.
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Project description:Rhodopseudomonas palustris CGA009 Transcriptome or Gene expression
| PRJNA976412 | ENA
Project description:Paraburkholderia phymatum is a beta-proteobacterium, which lives in the soil and is able to enter nitrogen-fixing symbiosis with different legumes. The biological nitrogen fixation (BNF) process is of great ecological and agronomic importance. We previously showed that the expression of the key P. phymatum BNF enzyme – the nitrogenase –is regulated by the sigma factor σ54 (or RpoN) inside root nodules. This study focused on identifying the σ54 regulon of P. phymatum grown in nitrogen limited conditions using RNA-Sequencing. Among the genes significantly down-regulated in absence of σ54 we found those coding for a C4-dicarboxylate transport system (Bphy_0225-27), a flagellar biosynthesis cluster (Bphy_2926-64) and one of the two type 6 secretion system (T6SS-b) present in P. phymatum genome (Bphy_5978-97). Indeed, the σ54 mutant was unable to grow on C4 dicarboxylates (fumarate, malate and succinate) as the sole carbon source and was less motile compared to the wild-type strain. Both defects were complemented by adding rpoN in trans. Additionally, using reporter fusions we confirmed that T6SS-b expression is regulated by σ54. Finally, a σ54 mutant was less competitive than its parental strain against P. diazotrophica, suggesting a role of σ54 in controlling interbacterial competition.
2020-08-12 | GSE156048 | GEO
Project description:Rhodopseudomonas palustris, a nonsulphur purple photosynthetic bacteria, has been extensively investigated for its metabolic versatility including ability to produce hydrogen gas from sunlight and biomass. The availability of the finished genome sequences of six R. palustris strains (BisA53, BisB18, BisB5, CGA009, HaA2 and TIE-1) combined with online bioinformatics software for integrated analysis presents new opportunities to determine the genomic basis of metabolic versatility and ecological lifestyles of the bacteria species. The purpose of this investigation was to compare the functional annotations available for multiple R. palustris genomes to identify annotations that can be further investigated for strain-specific or uniquely shared phenotypic characteristics. A total of 2,355 protein family Pfam domain annotations were clustered based on presence or absence in the six genomes. The clustering process identified groups of functional annotations including those that could be verified as strain-specific or uniquely shared phenotypes. For example, genes encoding water/glycerol transport were present in the genome sequences of strains CGA009 and BisB5, but absent in strains BisA53, BisB18, HaA2 and TIE-1. Protein structural homology modeling predicted that the two orthologous 240 aa R. palustris aquaporins have water-specific transport function. Based on observations in other microbes, the presence of aquaporin in R. palustris strains may improve freeze tolerance in natural conditions of rapid freezing such as nitrogen fixation at low temperatures where access to liquid water is a limiting factor for nitrogenase activation. In the case of adaptive loss of aquaporin genes, strains may be better adapted to survive in conditions of high-sugar content such as fermentation of biomass for biohydrogen production. Finally, web-based resources were developed to allow for interactive, user-defined selection of the relationship between protein family annotations and the R. palustris genomes.
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