Andreas Krell

Learn More
Various abiotic and biotic parameters, including phytoplankton distribution, were studied to investigate seasonal changes within the fast-ice cover in Chupa Inlet, a freshwater-influenced Arctic-like fjord in Kandalaksha Bay (White Sea). Sea ice and under-ice water were collected along transects in the inlet in February and April 2002. Ice-texture analysis,(More)
Analysis of expressed sequence tags (ESTs) was performed to gain insights into cold adaptation in the polar diatom Fragilariopsis cylindrus Grunow. The EST library was generated from RNA isolated 5 days after F. cylindrus cells were shifted from approximately þ 51C to 1.81 C. A total of 1376 ESTs were sequenced from a non-normalized cDNA library and(More)
Antifreeze proteins (AFPs) provide protection for organisms subjected to the presence of ice crystals. The psychrophilic diatom Fragilariopsis cylindrus which is frequently found in polar sea ice carries a multitude of AFP isoforms. In this study we report the heterologous expression of two antifreeze protein isoforms from F. cylindrus in Escherichia coli.(More)
The quantitative and qualitative distribution of phytoplankton was investigated along five North–South transects in the eastern Weddell Sea during the transition from late autumn to winter. Relationships with the regional hydrography, progressing sea ice coverage, nutrient distribution and zooplankton are discussed and compared with data from other seasons.(More)
Ice-binding proteins (IBPs) have been isolated from various sea-ice organisms. Their characterisation points to a crucial role in protecting the organisms in sub-zero environments. However, their in situ abundance and diversity in natural sea-ice microbial communities is largely unknown. In this study, we analysed the expression and phylogenetic diversity(More)
Fragilariopsis cylindrus (Grunow) Willi Krieger, a bipolar psychrophilic and highly abundant diatom, experiences strong shifts in salinity during the formation of sea ice. We investigated the effects of osmotic stress due to an increased salt concentration from 34 to 70 practical salinity units (PSU) in conjunction with a temperature decrease from 0 C to )4(More)
geschaffen werden oder eher eine Dachmarke vorhandener Förderlinien sein? Welche Arten von Finanzierungsund Förderinstrumenten wird der EIC bereitstellen? Welche Auswahlkriterien werden für die Förderung disruptiver Innovationsprojekte herangezogen werden? Und welche Auswirkung wird der EIC auf das Budget der Forschungsförderung haben? Aus Sicht vieler(More)
In the framework of the ‘‘Ice Station POLarstern’’ (ISPOL) expedition in the western Weddell Sea, two sediment traps were deployed at 10 and 70m water depth under a drifting ice floe in December 2004. The amount and composition of the vertical particle flux under sea ice were determined during a period of 30 days in order to investigate the influence of(More)
  • 1