Bacteria
Ontology highlight
ABSTRACT:
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| DRR168501_1.fastq.gz | Fastqsanger.gz | |||
| DRR168501_2.fastq.gz | Fastqsanger.gz | |||
| DRR168502_1.fastq.gz | Fastqsanger.gz | |||
| DRR168502_2.fastq.gz | Fastqsanger.gz | |||
| DRR168503_1.fastq.gz | Fastqsanger.gz |
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Similar Datasets
Project description:The ecological significance of light perception in non-phototrophic bacteria remains largely elusive. In terrestrial environments, diurnal oscillations in light are often temporally coupled to other environmental changes, including increased temperature and evaporation. Here we report that light functions as an anticipatory cue that triggers protective adaptations to tolerate a future rapid loss of environmental water in leaf-associated Pseudomonas syringae pv. syringae (Pss) and other terrestrial pseudomonads. Global transcriptome analyses in Pss showed that light control occurs almost entirely through a bacteriophytochrome photoreceptor that senses red, far-red and blue wavelengths and influences 30% of the Pss genome. Bacteriophytochrome-mediated light control disproportionally upregulates water-stress adaptation functions and confers enhanced fitness when cells encounter light prior to water limitation. These data demonstrate that non-phototrophic bacteria can use light as a cue to mount an adaptive anticipatory response against a physiologically unrelated but ecologically coupled stress.
2023-09-27 | GSE232095 | GEO
Project description:Gemmatimonas phototrophica is the only phototrophic member of the recently discovered bacterial phylum Gemmatimonadetes. It was isolated from a freshwater lake in the Gobi desert and first described in 2014. So far, Gemmatimonas phototrophica is the only bacterium to have received a complete set of photosynthesis-related genes by horizontal gene transfer from an ancient phototrophic species from the phylum Proteobacteria. This organism illustrates the possibility for engineering phototrophic capability in a non-phototrophic organism and is therefore of great interest to the field of synthetic biology. The structure of the photosynthetic reaction center-light harvesting 1 complex is under investigation by cryo-EM. Proteomic analysis verified the identities of the expected protein components of this complex and, additionally revealed polypeptides that were previously undiscovered and could be mapped to the cryo-EM images.
2022-04-04 | PXD024609 | Pride
Project description:Bacteria have evolved many strategies to spare energy when nutrients become scarce. One widespread such strategy is facultative phototrophy, which helps heterotrophs supplement their energy supply using light. Our knowledge on the impact that such behaviors have on bacterial fitness and physiology is, however, still limited. Here, we study how a representative of the genus Porphyrobacter, in which aerobic anoxygenic phototrophy is ancestral, responds to different light regimes under nutrient limitation. We show that bacterial survival in stationary phase relies on functional reaction centers and varies depending on the light regime. Under dark‑light alternance, our bacterial model presents a diphasic life history dependent on phototrophy: during dark phases, the cells inhibit DNA replication and part of the population lyses and releases nutrients, while subsequent light phases allow for the recovery and renewed growth of the surviving cells. We correlate these cyclic variations with a pervasive pattern of rhythmic transcription which reflects global changes in diurnal metabolic activity. Finally, we demonstrate that, compared to either a phototrophy null mutant or a bacteriochlorophyll a overproducer, the wild type strain is better adapted to natural environments, where regular dark‑light cycles are interspersed with additional accidental dark episodes. Overall, our results highlight the importance of light‑induced biological rhythms in a new model of aerobic anoxygenic phototroph representative of an ecologically important group of environmental bacteria.
2023-10-12 | GSE245047 | GEO
Project description:Pseudomonas putida KT2440 encodes 3 homologs of the LitR/CarH family (designated PplR1–PplR3; Pseudomonas putida light-induced transcription; regulator), which is an adenosyl B12-dependent light-sensitive MerR family transcriptional regulator. Transcriptome and individual transcriptional analysis revealed the existence of a number of photo-inducible genes including pplR1, phrB (encoding DNA photolyase), cfaA (cyclopropane synthase), folE (GTP cyclohydrolase I), cryB (cryptochrome-like protein), and multiple hypothetical genes. Transcriptional analysis based on a β-galactosidase reporter assay with single-, double-, and triple-knockout mutants of pplR1–pplR3 showed that deletion of pplR1–pplR3 completely abolished the light-inducible transcription in P. putida, which indicates that the transcription of light-inducible genes is under the ternary regulation of PplR proteins. DNase I footprint assay showed that PplR1 protein specifically binds to the promoter regions of light-inducible genes, suggesting a consensus PplR1-binding site, 5’-T(G/A)TACAn12TGTA(C/T)A-3’, predicted upon nucleotide sequence alignment. The disruption of cobalamin biosynthesis cluster did not affect the light-inducible transcription; however, disruption of ppSB1-LOV and ppSB2-LOV, a blue light photoreceptor genes, which are adjacent to pplR3 and pplR2, respectively, led to the complete loss of light-inducible transcription. Overall, the results suggest that 3 PplR and 2 PpSB-LOV regulate light-induced gene transcription in response to illumination. The high conservation of the pplR/ppSB-LOV cognate pair in Pseudomonas spp. suggests that the response and adaptation to light is similarly regulated in the group of non-phototrophic bacteria.
2016-10-13 | GSE87863 | GEO
Project description:Organic substrate transfer between photoautotrophic and heterotrophic microbes in the surface ocean is a central but poorly understood process in the global carbon cycle. This study developed a co-culture system of marine diatom Thalassiosira pseudonana and heterotrophic bacterium Ruegeria pomeroyi, and addressed diel changes in phytoplankton endometabolite production using nuclear magnetic resonance (NMR) and bacterial metabolite consumption using gene expression. Here we deposit data for NMR analysis from the study. Samples were collected every 6 hours over two days under a diel light cycle. During the course of the study, we observed an increase in some phytoplankton endometabolites presumably due to the effects of the associated bacteria. We introduced an additional experiment and tested this possibility by comparing phytoplankton endometabolite accumulation between axenic treatments and bacteria coculture treatments.
2020-10-18 | ST001512 | MetabolomicsWorkbench
Project description:Here we show that the phytochrome-less chlorophyte Chlamydomonas reinhardtii retains a functional pathway to synthesize the linear tetrapyrrole (bilin) precursor of the phytochrome chromophore. Reverse genetic, metabolic inactivation and bilin rescue experiments establish that this pathway is needed for heme iron acquisition and for the diurnal transition to phototrophic growth. RNA-Seq measurements reveal a bilin-dependent signaling network that is necessary for the heterotrophic to phototrophic transition. These results imply the presence of a novel bilin sensor pathway that may be widely distributed amongst oxygenic photosynthetic organisms. We isolated RNA from heterotrophic suspension cultures of 4A+ WT and the hmox1 mutant grown in the presence or absence of 0.1 mM BV IXM-NM-1 before and after transfer to low light.
2013-01-10 | E-GEOD-40031 | biostudies-arrayexpress
Project description:Dictyostelium discoideum amoebae feed by ingesting bacteria, then killing them in phagosomes. Ingestion and killing of different bacteria have been shown to rely on largely different molecular mechanisms. One would thus expect that D. discoideum adapts its ingestion and killing machinery when encountering different bacteria. In this study, we investigated by RNA sequencing if and how D. discoideum amoebae respond to the presence of different bacteria by modifying their gene expression patterns. Each bacterial species analyzed induced a specific modification of the transcriptome. Bacteria such as Bacillus subtilis, Klebsiella pneumoniae, or Mycobacterium marinum induced a specific and different transcriptional response, while Micrococcus luteus did not trigger a significant gene regulation. Although folate has been proposed to be one of the key molecules secreted by bacteria and recognized by hunting amoebae, it elicited a very specific and restricted transcriptional signature, distinct from that triggered by any bacteria analyzed here. Our results indicate that D. discoideum amoebae respond in a highly specific, almost non-overlapping manner to different species of bacteria. We additionally identify specific sets of genes that can be used as reporters of the response of D. discoideum to different bacteria.
2020-02-08 | GSE144912 | GEO
Project description:Small RNA sequencing shows that there are no Caenorhabditis elegans endo siRNAs made against the OxyS non-coding RNA. Sequencing of small RNAs from C. elegans fed bacteria overexpressing the non-coding RNA OxyS, control samples fed either standard E. coli or one without the OxyS RNA, an rde-4 deletion mutant deficient in endo siRNA production and the OxyS-overexpressing bacteria itself. 5' independent samples were treated with the enzyme RNA 5' polyphosphatase to remove 5' triphosphate; 5' dependent samples were not treated with 5' polyphosphatase.
2016-07-05 | E-GEOD-64990 | biostudies-arrayexpress
Project description:Aerobic anoxygenic phototrophic bacteria (AAPs) of the Roseobacter group are abundant in the photic zone of the marine environment. Dinoroseobacter shibae, a typical representative, converts light into additional energy that enhances its survival under nutrient-depletion. AAPs produce cytotoxic singlet oxygenunder light exposition, but D. shibae developed mechanisms to counteract the lethal effects of illumination. Recent studies documented a pivotal role of extrachromosomal elements (ECRs) for the ecological fitness of roseobacters, and here we investigated their significance for the adaptation to specific environmental stress. D. shibae possessing five ECRs, i.e. three chromids and two plasmids, was starved for four weeks in the dark and light/dark cycles and the survival strategy was evaluated using transcriptomics. Few genes on the chromosome showed differential expression between non-starved and starved cells, in particular those with a role in oxidative stress response and photosynthesis. Extrachromosomal genes in contrast showed a systematic loss of transcriptional activity, especially in the dark starved cells. The observed silencing of gene expression was not due to plasmid loss, because all five ECRs were stably maintained. Exceptionally, the smallest 72-kb replicon was the least downregulated, and one region with genes for singlet oxygen stress response was even strongly activated under light/dark cycle. A ?72-kb curing mutant completely lost the ability to benefit from AAP under starvation, and we could thus document the essential role of the 72-kb chromid to light-stress adaptation. . Our data moreover suggest that the four ECRs of D. shibae without a vital function are transcriptionally silenced under starvation. Loop-design, two biological replicates of D. shibae DFL12T cultivated in artificial salt water medium with succinate as carbon source and 12/12 light-dark cycles. After reaching stationary phase the cells were starved for 4 weeks in the dark or under light-dark cycle.
2015-01-01 | E-GEOD-62869 | biostudies-arrayexpress