1. november kl. 9.00 - Geologisk Museum, København This PhD thesis investigates bacterial mercury transformation in the High Arctic. Bacteria from snow, freshwater and sea-ice brine from Northeastern Greenland were isolated and characterized regarding their ability to reduce ionic mercury.

01.11.2010

Annette K. Møller, MSc, Department of Biology and National Environmental Research Institute at Aarhus University.

Title: “Bacterial reduction of mercury in the High Arctic”

This PhD thesis investigates bacterial mercury transformation in the High Arctic. Bacteria from snow, freshwater and sea-ice brine from Northeastern Greenland were isolated and characterized regarding their ability to reduce ionic mercury. It was found that up 30% of culturable bacteria exhibited mercury resistance and at least 25% of these were able to reduce ionic mercury to elemental mercury. The genetic elements responsible for mercury resistance (merA genes) in these bacteria were found to be diverse; some merA genes were identical to well-known merA genes from bacteria originating from temperate environments while other merA genes were novel.

Furthermore, the microbial communities in High Arctic snow and freshwater was characterized both by culture dependent and culture independent methods (pyrosequencing of 16S rRNA) and were found to have a high diversity and heterogeneity presumably reflecting the environments from which they were identified.

Supervisor:
Søren J. Sørensen, Niels Kroer, Henrik Skov & Tamar Barkay.

Evaluation committee:
Associate professor Anders Priemé, Section for Microbiology, Department of Biology, University of Copenhagen
Professor Vigdis Torsvik, Department of Biology, Centre for Geobiology, University of Bergen, Norway
Professor Åke Hageström, Swedish Institute for the Marine Environment, Gothenburg, Sweden

Time: Monday November 1, 2010, at 9:00 am

Place: The auditorium at The Geological Museum
Øster Voldgade 5-7
1350 Copenhagen K

Other: The thesis is available for the public at Molecular Microbial Ecology Group, Sølvgade 85H,
1307 Copenhagen K

adh/FORS/1781