Lars Ganzert

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In Arctic wet tundra, microbial controls on organic matter decomposition are likely to be altered as a result of climatic disruption. Here, we present a study on the activity, diversity and vertical distribution of methane-cycling microbial communities in the active layer of wet polygonal tundra on Herschel Island. We recorded potential methane production(More)
Permafrost environments in the Arctic are characterized by extreme environmental conditions that demand a specific resistance from microorganisms to enable them to survive. In order to understand the carbon dynamics in the climate-sensitive Arctic permafrost environments, the activity and diversity of methanogenic communities were studied in three different(More)
Microorganisms inhabit very different soil habitats in the ice-free areas of Antarctica, playing a major role in nutrient cycling in cold environments. We studied the soil characteristics and the dominant bacterial composition from nine different soil profiles located on Livingston Island (maritime Antarctica). The total carbon (TC) and total nitrogen (TN)(More)
Greenland is one of the regions of interest with respect to climate change and global warming in the Northern Hemisphere. Little is known about the structure and diversity of the terrestrial bacterial communities in ice-free areas in northern Greenland. These soils are generally poorly developed and usually carbon- and nitrogen-limited. Our goal was to(More)
A methanogenic archaeon, strain SMA-21(T), was isolated from a permafrost-affected soil by serial dilution in liquid medium. The cells were non-motile, stained Gram-negative and grew as irregular cocci with a diameter of 1.3-2.5 µm. Optimal growth was observed at 28 °C, pH 7.8 and 0.02 M NaCl. The strain grew on H2/CO2, methanol and acetate, but not on(More)
A psychrotolerant, Gram-stain-positive, yellow-pigmented, aerobic rod, designated SK1(T), was isolated from a soil sample collected from Store Koldewey, north-east Greenland. Cells were catalase- and methyl red-positive, produced H(2)S and produced acid from glucose, mannitol and salicin. Strain SK1(T) was able to grow between -6 and 28 °C, with an optimum(More)
A cold-tolerant, yellow-pigmented, Gram-positive, motile, facultatively anaerobic bacterial strain, LI1(T), was isolated from a moss-covered soil from Livingston Island, Antarctica, near the Bulgarian station St. Kliment Ohridski. Comparative 16S rRNA gene sequence-based phylogenetic analysis placed the strain in a clade with the species Leifsonia(More)
A novel methanogenic archaeon, strain MC-15(T), was isolated from a floating biofilm on a sulphurous subsurface lake in Movile Cave (Mangalia, Romania). Cells were non-motile sarcina-like cocci with a diameter of 2-4 µm, occurring in aggregates. The strain was able to grow autotrophically on H2/CO2. Additionally, acetate, methanol, monomethylamine,(More)
The response of methanogens to thawing permafrost is an important factor for the global greenhouse gas budget. We tracked methanogenic community structure, activity, and abundance along the degradation of sub-Arctic palsa peatland permafrost. We observed the development of pronounced methane production, release, and abundance of functional (mcrA)(More)
A novel psychrotolerant, Gram-negative, shiny white, curved-rod-shaped, facultatively anaerobic bacterium PB1(T) was isolated from a soil sample collected from a glacier forefield of the Larsemann Hills, East Antarctica. Isolate PB1(T) has catalase and low urease activity and hydrolyses gelatin and starch. Strain PB1(T) is able to grow between -5 °C and 30(More)