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pmoA based detection of methanotrophic bacteria in coal-bed rocks of the Lublin Coal basin

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Pytlak A., Kuzniar A., Stepniewska Z.

Acta Agrophysica

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2012

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tom 19

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nr 2

Methane is one of the most important greenhouse gases. In spite of its low mixing ratio (1775 ppbv), it is responsible for 20-30% of global warming. However, factors influencing methane fluxes to the atmosphere from different sources are still under debate. One of the most important elements of the methane cycle are methanotrophic bacteria. This unique group of Proteobacteria utilises methane at various levels, from atmospheric concentrations to several percentages, using molecular oxygen. Methanotrophs have been found in many terrestrial, aquatic and subsurface environments, there is however little information about methanotrophs connected with coal deposits. In the study, the presence of methanotrophic bacteria in coal–associated rocks of the Lublin Coal Basin (LCB) was confirmed by the methanotrophic activity tests of fresh and autoclaved samples from depths of 914 m and 997 m below the surface. Methanotrophs were also successfully enriched on nitrate minimal salts medium and identified based on the cloned pmoA sequences. It was found that methane-oxidising bacteria present in the LCB are highly similar to Methylosinus, Methylocys-tis and Methylocaldum species. It was assumed that biological oxidation may be one of the processes influencing methane concentrations in coalbeds and that rocks excavated with coal may serve e.g. as methanotrophically active covers preventing CH4 emission from landfills.

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Methanotrophs responsible for methane oxidation in natural peats from Polesie Lubelskie Region

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Szafranek-Nakonieczna A., Stepniewska Z., Woloszyn A., Ciepielski J.

Acta Agrophysica

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2012

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tom 19

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nr 1

The potential of methanotrophic activity (MTA) has been investigated under labo-ratory conditions in three types of peatland profiles: high (H), transition (T) and low (L) originating from Polesie Lubelskie Region. Selected peat samples differed in respect of pH, TOC, von Post index and moisture. The experiment was conducted at natural moisture (198-719 %w/w) with dif-ferent ranges of both, temperature (5, 10 and 20°C) and CH4 enrichment (1 and 5%v/v). The highest MTA (19.69-155.79 mg CH4kg D.W.-1 d-1) was observed at 20°C. Regardless of temperature, MTA was lower (1.38-51.16 mg CH4 kg D.W.-1 d-1) when peat samples were incubated in atmosphere enriched in 1% than in 5% CH4 v/v (4.75-191.26 mg CH4kg D.W.-1 d-1). Strong influence of tem-perature and sampling sites on MTA was also noted. Total DNA was isolated from the most active (20°C, 5% CH4 v/v) peat samples from each site and the PCR (polimerase chain reaction) amplify-ing of genes pmoA (primers A189f/mb661r) and sequence 16S rRNA (primers Type If /Type Ir and Type IIf/Type IIr) specific for methanotrophic bacteria were carried out. Positive results of PCR with primers of pmoA gene after sequencing confirmed that methanotrophs from L point belong to family Methylococcaceae, while 16S rRNA gene sequences from microorganisms inhabiting H peat demonstrated the highest similarity to genus Methylocystis and Methylosinus.

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Methanotrophic bacteria and the impact of soil physical conditions on their activity

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Stepniewski W., Rozej A.

International Agrophysics

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2000

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tom 14

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nr 1

Ograniczanie wyników

2 Acta Agrophysica

1 International Agrophysics

2 Stepniewska Z.

1 Ciepielski J.

1 Kuzniar A.

1 Pytlak A.

1 Rozej A.

1 Stepniewski W.

1 Szafranek-Nakonieczna A.

1 Woloszyn A.

2 2012

1 2000

pmoA based detection of methanotrophic bacteria in coal-bed rocks of the Lublin Coal basin

Methanotrophs responsible for methane oxidation in natural peats from Polesie Lubelskie Region

Methanotrophic bacteria and the impact of soil physical conditions on their activity