A methanotrophic bacterium to enable direct methane capture for climate mitigation
Ontology highlight
ABSTRACT:
ORGANISM(S): Methylotuvimicrobium buryatense
PROVIDER: GSE221011 | GEO | 2023/08/02
REPOSITORIES: GEO
Similar Datasets
Project description:Methylomicrobium buryatense 5GB1 is an obligate methylotroph, which grows on methane or methanol with similar growth rates. Core metabolic pathways are similar on both substrates, but recent studies of methane metabolism suggest that growth on methanol might have significant differences from growth on methane. In this study, both a targeted metabolomics approach as well as a 13C tracer approach have been taken to understand core carbon metabolism in M. buryatense 5GB1 during methanol growth, to determine whether such differences occur. Targeted metabolomics analyses were performed on both methane and methanol cultures to identify metabolic nodes with altered fluxes. Several key metabolites showed significant differences in pool size. Noticeably, 2-keto-3-deoxy-6-phosphogluconate (KDPG) showed much larger pools under methanol culture, suggesting the Entner-Doudoroff (ED) pathway was more active. Intermediates in other parts of metabolism also showed differences in pool sizes under methanol growth. A systematic shift of active core metabolism is proposed to explain the changes. In order to distinguish flux partition differences at the C3-C4 node, 13C tracer analysis was also applied to methanol-grown cultures. Using the experimental results as constraints, we applied flux balance analysis to determine the metabolic flux phenotype of M. buryatense 5GB1 growing on methanol. The resulting new insights into core metabolism of this methanotroph provide an improved basis for future strain design.
2019-04-17 | GSE110541 | GEO
Project description:Natural and anthropogenic wetlands are main sources of the atmospheric greenhouse gas methane. Methane emissions from wetlands are mitigated by methanotrophic microorganisms and by processes at the oxic-anoxic interface, such as sulfur cycling, that reduce the activity of methanogens. In this study, we obtained a pure culture (strain HY1) of a versatile wetland methanotroph that oxidizes various organic and inorganic compounds. This strain represents (i) the first isolate that can aerobically oxidize both methane and reduced sulfur compounds and (ii) a new alphapoteobacterial species, named Candidatus Methylovirgula thiovorans. Genomic and proteomic analyses showed that soluble methane monooxygenase and XoxF-type alcohol dehydrogenases are the only enzymes for methane and methanol oxidation, respectively. Unexpectedly, strain HY1 harbors various pathways for respiratory sulfur oxidation and oxidized reduced sulfur compounds to sulfate using the Sox-rDsr pathway (without SoxCD) and the S4I system. It employed the Calvin-Benson-Bassham cycle for CO2 fixation during chemolithoautotrophic growth on the reduced sulfur compounds. Methane and thiosulfate were independently and simultaneously oxidized by strain HY1 for growth. Proteomic and microrespiratory analyses showed that the metabolic pathways for methane and thiosulfate oxidation were induced in the presence of their substrates. The discovery of this versatile methanotroph demonstrates that methanotrophy and thiotrophy is compatible in a single bacterium and adds a new aspect to interactions of methane and sulfur cycles in oxic-anoxic interface environments.
2022-07-11 | PXD025979 | Pride
Project description:Methanotrophs, which help regulate atmospheric levels of methane, are active in diverse natural and man-made environments. This range of habitats and the feast-famine cycles seen by many environmental methanotrophs suggest that methanotrophs dynamically mediate rates of methane oxidation. Global methane budgets require ways to account for this variability in time and space. Functional gene biomarker transcripts are increasingly being studied to inform the dynamics of diverse biogeochemical cycles. Previously, per-cell transcript levels of the methane oxidation biomarker, pmoA, were found to vary quantitatively with respect to methane oxidation rates in model aerobic methanotroph, Methylosinus trichosporium OB3b. In the present study, these trends were explored for two additional aerobic methanotroph pure cultures, Methylocystis parvus OBBP and Methylomicrobium album BG8. At steady-state conditions, per cell pmoA mRNA transcript levels strongly correlated with per cell methane oxidation across the three methanotrophs across many orders of magnitude of activity (R2 = 0.91). Additionally, genome-wide expression data (RNA-seq) were used to explore transcriptomic responses of steady state M. album BG8 cultures to short-term CH4 and O2 limitation. These limitations induced regulation of genes involved in central carbon metabolism (including carbon storage), cell motility, and stress response.
2021-11-17 | GSE188821 | GEO
Project description:RNA-Seq profiling of Methylomicrobium alcaliphilum strain 20Z grown in batch on methane. The RNA-Seq work is one part of a systems approach to characterizing metabolism of 20Z during growth on methane. We demonstrate that methane assimilation is coupled with a highly efficient pyrophosphate-mediated glycolytic pathway, which under O2 limitation participates in a novel form of fermentation-based methanotrophy. This surprising discovery suggests a novel mode of methane utilization in oxygen-limited environments, and opens new opportunities for a modular approach towards producing a variety of excreted chemical products using methane as a feedstock.
2013-09-25 | GSE51145 | GEO
Project description:RNA-Seq profiling of Methylomicrobium alcaliphilum strain 20Z grown in batch on methane. The RNA-Seq work is one part of a systems approach to characterizing metabolism of 20Z during growth on methane. We demonstrate that methane assimilation is coupled with a highly efficient pyrophosphate-mediated glycolytic pathway, which under O2 limitation participates in a novel form of fermentation-based methanotrophy. This surprising discovery suggests a novel mode of methane utilization in oxygen-limited environments, and opens new opportunities for a modular approach towards producing a variety of excreted chemical products using methane as a feedstock. Four replicates of batch growth
2013-09-25 | E-GEOD-51145 | biostudies-arrayexpress
Project description:Aerobic methanotrophic bacteria use methane as their sole source of carbon and energy and serve as a major sink for the potent greenhouse gas methane in freshwater ecosystems. Despite this important environmental role, little is known about the molecular details of how these organisms interact in the environment. Many bacterial species use quorum sensing systems to regulate gene expression in a density-dependent manner. We have identified a quorum sensing system in the genome of Methylobacter tundripaludum, a dominant methane-oxidizer in methane enrichments of sediment from Lake Washington (Seattle, WA, USA). We determined that M. tundripaludum primarily produces N-3-hydroxydecanoyl-L-homoserine lactone (3-OH-C10-HSL) and that production is governed by a positive feedback loop. We then further characterized this system by determining which genes are regulated by quorum sensing in this methane-oxidizer using RNA-seq, and discovered this system regulates the expression of a novel nonribosomal peptide synthetase biosynthetic gene cluster. These results identify and characterize a mode of cellular communication in an aerobic methane-oxidizing bacterium.
2016-08-16 | GSE85617 | GEO
Project description:Aerobic methanotrophic bacteria use methane as their sole source of carbon and energy and serve as a major sink for the potent greenhouse gas methane in freshwater ecosystems. Despite this important environmental role, little is known about the molecular details of how these organisms interact in the environment. Many bacterial species use quorum sensing systems to regulate gene expression in a density-dependent manner. We have identified a quorum sensing system in the genome of Methylobacter tundripaludum, a dominant methane-oxidizer in methane enrichments of sediment from Lake Washington (Seattle, WA, USA). We determined that M. tundripaludum primarily produces N-3-hydroxydecanoyl-L-homoserine lactone (3-OH-CÂ10-HSL) and that production is governed by a positive feedback loop. We then further characterized this system by determining which genes are regulated by quorum sensing in this methane-oxidizer using RNA-seq, and discovered this system regulates the expression of a novel nonribosomal peptide synthetase biosynthetic gene cluster. These results identify and characterize a mode of cellular communication in an aerobic methane-oxidizing bacterium. Samples are 2 sets of biological replicates of a Methylobacter tundripaludum strain 21/22 mutant where the acyl-homoserine lactone (AHL) synthase gene mbaI (T451DRAFT_0796) has been deleted. The mutant strain was grown to log (48 hours) or stationary (68 hours) phase in the absence or presence of the AHL 3-OH-C10-HSL.
2016-08-16 | E-GEOD-85617 | biostudies-arrayexpress
Project description:The bacteria that grow on methane aerobically (methanotrophs) support populations of non-methanotrophs in the natural environment by excreting methane-derived carbon. One group of excreted compounds are short-chain organic acids, generated in highest abundance when cultures are grown under O2-starvation. We examined this O2-starvation condition in the methanotroph Methylomicrobium buryatense 5GB1C . Under prolonged O2-starvation in a closed vial, this methanotroph increases the amount of acetate excreted about 10-fold, but the formate, lactate, and succinate excreted do not respond to this culture condition. In bioreactor cultures, the amount of each excreted product is similar across a range of growth rates and limiting substrates, including O2-limitation. A set of mutants were generated in genes predicted to be involved in generating or regulating excretion of these compounds and tested for growth defects, and changes in excretion products. The phenotypes and associated metabolic flux modeling suggested that in M. buryatense 5GB1C, formate and acetate are excreted in response to redox imbalance, and the resulting metabolic state represents a combination of fermentation and respiration metabolism.
2017-08-24 | GSE101981 | GEO
Project description:Connecting genes to phenotypic traits in bacteria is often challenging because of a lack of environmental cues in laboratory settings. However, laboratory-based model ecosystems offer a means to better account for natural conditions compared to standard planktonic cultures, aiding in the linking of genotypes and phenotypes. Here, we present a simple, cost-effective, laboratory-based model ecosystem to study aerobic methane-oxidizing bacteria (methanotrophs). This system, referred to as the gradient syringe, is made by inoculating bacteria into semi-solid agarose held within a disposable syringe. Empty space at one end of the syringe is flushed with methane gas, while the other end is open to the atmosphere through a sterile filter. We show this system replicates the methane-oxygen counter gradient typically found in the natural soil environment of methanotrophs. Culturing the methanotroph Methylomonas sp. strain LW13 in this system produced a distinct horizontal band at the intersection of the counter gradient, which we discovered was due not to increased cell growth at this location but instead to an increased amount of extracellular polymeric substances (EPS). We also discovered that different methanotrophic taxa formed EPS bands with distinct locations and morphologies when grown in the methane-oxygen counter gradient. By comparing transcriptomic data from LW13 growing within and surrounding this EPS band, we identified genes implicated in cell growth and EPS formation within the gradient syringe, and validated the involvement of these genes with knockout strains. This work highlights the use of a laboratory-based model ecosystem that more closely mimics the natural environment to uncover methanotroph phenotypes missing from standard planktonic cultures, and link these phenotypes their genetic determinants.
2023-10-05 | GSE243827 | GEO
Project description:The rapid increase of the potent greenhouse gas methane in the atmosphere creates great urgency to develop and deploy technologies for methane mitigation. One approach to removing methane is to use bacteria for which methane is their carbon and energy source (methanotrophs). Such bacteria naturally convert methane to CO2 and biomass, a value-added product and a cobenefit of methane removal. Typically, methanotrophs grow best at around 5,000 to 10,000 ppm methane, but methane in the atmosphere is 1.9 ppm. Air above emission sites such as landfills, anaerobic digestor effluents, rice paddy effluents, and oil and gas wells contains elevated methane in the 500 ppm range. If such sites are targeted for methane removal, technology harnessing aerobic methanotroph metabolism has the potential to become economically and environmentally viable. The first step in developing such methane removal technology is to identify methanotrophs with enhanced ability to grow and consume methane at 500 ppm and lower. We report here that some existing methanotrophic strains grow well at 500 ppm methane, and one of them, Methylotuvimicrobium buryatense 5GB1C, consumes such low methane at enhanced rates compared to previously published values. Analyses of bioreactor-based performance and RNAseq-based transcriptomics suggest that this ability to utilize low methane is based at least in part on extremely low non-growth-associated maintenance energy and on high methane specific affinity. This bacterium is a candidate to develop technology for methane removal at emission sites. If appropriately scaled, such technology has the potential to slow global warming by 2050.
| S-EPMC10466089 | biostudies-literature