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Gunnar Øregaard vart Ph.D. ritgerð 15. september


Mánadagin 15. september vardi Gunnar Øregaard, mikrobiologur, Ph.D. ritgerð sína: "Bacteria in Mercury Contaminated Soils and Horizontal Gene Transfer" við Københavns Universitet.

Opponentarnir vóru:
Sten Struwe, Sektionen for evolution og mikrobiologi, Biologisk Institut, Københavns Universitet

J.D. van Elsas, Department of Microbial Ecology, Rijksuniversiteit Groningen

Peter Westermann, Sektionen for bioteknologi, Aalborg Universitet

Les meira um Gunnar Øregaard í Heilagrunninum

Enskt abstract av ritgerðini:
Mercury contaminated soil from Oak Ridge National Laboratory (TN, USA) was ex-amined with focus on the microbial communities. The bacterial soil communities were diverse both genotypically and by mercury resistance functionality, suggesting good adaptation to mercury. Plasmids conferring resistance to mercury were isolated from different soil depths confirming soil community potential of disseminating mercury resistance by horizontal gene transfer. Two different protocols for cultivation of soil bacteria allowed isolation of bacteria not previously recognised as mercury resistant, belonging to the phyla Bacteroidetes and ?-Proteobacteria. Higher overall cultivation efficiency was obtained by both methods, compared to traditional plating on rich media. Real time horizontal gene transfer studies with ?-Proteobacteria showed that gene transfer occurs frequently in both rhizosphere and aquatic environments and that gene transfer by cultivation underestimates the true number of transconjugants.