In Situ Analyses of Methane Oxidation Associated with the Roots and Rhizomes of a Bur Reed, Sparganium eurycarpum, in a Maine Wetland.

ABSTRACT The abundances and activities of aerobic methane-oxidizing bacteria (MOB) were compared in depth profiles of littoral and profundal sediments of Lake Constance, Germany. Abundances were determined by quantitative PCR (qPCR) targeting the pmoA gene and by fluorescence in situ hybridization (FISH), and data were compared to methane oxidation rates calculated from high-resolution concentration profiles. qPCR using type I MOB-specific pmoA primers indicated that type I MOB represented a major proportion in both sediments at all depths. FISH indicated that in both sediments, type I MOB outnumbered type II MOB at least fourfold. Results obtained with both techniques indicated that in the littoral sediment, the highest numbers of methanotrophs were found at a depth of 2 to 3 cm, corresponding to the zone of highest methane oxidation activity, although no oxygen could be detected in this zone. In the profundal sediment, highest methane oxidation activities were found at a depth of 1 to 2 cm, while MOB abundance decreased gradually with sediment depth. In both sediments, MOB were also present at high numbers in deeper sediment layers where no methane oxidation activity could be observed.

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Cooccurrence of Aerobic and Anaerobic Methane Oxidation in the Water Column of Lake Plußsee

Applied and Environmental Microbiology ◽

10.1128/aem.71.12.8925-8928.2005 ◽

2005 ◽

Vol 71 (12) ◽

pp. 8925-8928 ◽

Cited By ~ 101

Author(s):

Gundula Eller ◽

Layla Känel ◽

Martin Krüger

Keyword(s):

Water Column ◽

Methane Oxidation ◽

Eutrophic Lake ◽

Anaerobic Methane Oxidation ◽

Sulfide Concentration ◽

High Cell ◽

Cell Numbers ◽

Aerobic And Anaerobic ◽

Hydrogen Sulfide Concentration

ABSTRACT Dissolved methane was investigated in the water column of eutrophic Lake Plußsee and compared to temperature, oxygen, and sulfide profiles. Methane concentrations and δ-13C signatures indicated a zone of aerobic methane oxidation and additionally a zone of anaerobic methane oxidation in the anoxic water body. The latter coincided with a peak in hydrogen sulfide concentration. High cell numbers of aerobic and anaerobic methane-oxidizing microorganisms were detected by fluorescence in situ hybridization (FISH) or the more sensitive catalyst-amplified reporter deposition-FISH, respectively, in these layers.

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Methanotrophic activity and diversity in different <i>Sphagnum magellanicum</i> dominated habitats in the southernmost peat bogs of Patagonia

Biogeosciences ◽

10.5194/bg-9-47-2012 ◽

2012 ◽

Vol 9 (1) ◽

pp. 47-55 ◽

Cited By ~ 42

Author(s):

N. Kip ◽

C. Fritz ◽

E. S. Langelaan ◽

Y. Pan ◽

L. Bodrossy ◽

...

Keyword(s):

Methane Oxidation ◽

Northern Hemisphere ◽

Water Levels ◽

Peat Bogs ◽

Oxidation Activity ◽

Moss Species ◽

Sphagnum Mosses ◽

Methane Concentrations ◽

Sphagnum Magellanicum

Abstract. Sphagnum peatlands are important ecosystems in the methane cycle. Methanotrophs living inside the dead hyaline cells or on the Sphagnum mosses are able to act as a methane filter and thereby reduce methane emissions. We investigated in situ methane concentrations and the corresponding activity and diversity of methanotrophs in different Sphagnum dominated bog microhabitats. In contrast to the Northern Hemisphere peat ecosystems the temperate South American peat bogs are dominated by one moss species; Sphagnum magellanicum. This permitted a species-independent comparison of the different bog microhabitats. Potential methane oxidizing activity was found in all Sphagnum mosses sampled and a positive correlation was found between activity and in situ methane concentrations. Substantial methane oxidation activity (23 μmol CH4 gDW−1 day−1) was found in pool mosses and could be correlated with higher in situ methane concentrations (>35 μmol CH4 l−1 pore water). Little methanotrophic activity (<0.5 μmol CH4 gDW−1 day−1) was observed in living Sphagnum mosses from lawns and hummocks. Methane oxidation activity was relatively high (>4 μmol CH4 gDW−1 day−1) in Sphagnum litter at depths around the water levels and rich in methane. The total bacterial community was studied using 16S rRNA gene sequencing and the methanotrophic communities were studied using a pmoA microarray and a complementary pmoA clone library. The methanotrophic diversity was similar in the different habitats of this study and comparable to the methanotrophic diversity found in peat mosses from the Northern Hemisphere. The pmoA microarray data indicated that both alpha- and gammaproteobacterial methanotrophs were present in all Sphagnum mosses, even in those mosses with a low initial methane oxidation activity. Prolonged incubation of Sphagnum mosses from lawn and hummock with methane revealed that the methanotrophic community present was viable and showed an increased activity within 15 days. The high abundance of methanotrophic Methylocystis species in the most active mosses suggests that these might be responsible for the bulk of methane oxidation.

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Assessment of microbial methane oxidation above a petroleum-contaminated aquifer using a combination of in situ techniques

Journal of Geophysical Research Atmospheres ◽

10.1029/2006jg000363 ◽

2008 ◽

Vol 113 (G2) ◽

pp. n/a-n/a ◽

Cited By ~ 13

Author(s):

Karina Urmann ◽

Martin H. Schroth ◽

Matthias Noll ◽

Graciela Gonzalez-Gil ◽

Josef Zeyer

Keyword(s):

Methane Oxidation ◽

Contaminated Aquifer ◽

In Situ Techniques

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Large Freshwater Phages with the Potential to Augment Aerobic Methane Oxidation

10.1101/2020.02.13.942896 ◽

2020 ◽

Cited By ~ 3

Author(s):

Lin-Xing Chen ◽

Raphaël Méheust ◽

Alexander Crits-Christoph ◽

Katherine D. McMahon ◽

Tara Colenbrander Nelson ◽

...

Keyword(s):

Methane Oxidation ◽

Oxidation Catalyst ◽

Freshwater Lakes ◽

High Similarity ◽

Bacterial Genomes ◽

Particulate Methane Monooxygenase ◽

Ecosystem Impacts ◽

Abundance Patterns ◽

Transcriptomics Data

AbstractThere is growing evidence that phages with unusually large genomes are common across various natural and human microbiomes, but little is known about their genetic inventories or potential ecosystem impacts. Here, we reconstructed large phage genomes from freshwater lakes known to contain bacteria that oxidize methane. Twenty-two manually curated genomes (18 are complete) ranging from 159 to 527 kbp in length were found to encode the pmoC gene, an enzymatically critical subunit of the particulate methane monooxygenase, the predominant methane oxidation catalyst in nature. The phage-associated PmoC show high similarity (> 90%) and affiliate phylogenetically with those of coexisting bacterial methanotrophs, and their abundance patterns correlate with the abundances of these bacteria, supporting host-phage relationships. We suggest that phage PmoC has similar functions to additional copies of PmoC encoded in bacterial genomes, thus contribute to growth on methane. Transcriptomics data from one system showed that the phage-associated pmoC genes are actively expressed in situ. Augmentation of bacterial methane oxidation by pmoC-phages during infection could modulate the efflux of this powerful greenhouse gas into the environment.

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A design of a fixed bed plasma DRIFTS cell for studying the NTP-assisted heterogeneously catalysed reactions

Catalysis Science & Technology ◽

10.1039/d0cy00036a ◽

2020 ◽

Vol 10 (5) ◽

pp. 1458-1466

Author(s):

Cristina Stere ◽

Sarayute Chansai ◽

Rahman Gholami ◽

Kanlayawat Wangkawong ◽

Amit Singhania ◽

...

Keyword(s):

Methane Oxidation ◽

Thermal Plasma ◽

Fixed Bed ◽

Plasma Drifts ◽

Non Thermal Plasma

A newly developed DRIFTS cell for the in situ study of non-thermal plasma-assisted heterogeneously catalysed reactions is presented and evaluated using methane oxidation over a Pd/Al2O3 catalyst.

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