Chemical and microbial ecology of boreal Demosponges from the Korsfjord

Many marine sponges produce and store pharmacologically-active metabolites. There is an ongoing discussion as to whether some of these compounds are produced by the sponge itself, or by associated bacteria which can account for more than 60% of the sponge biomass. Co-metabolic activity between sponge cells and sponge associated bacteria (SAB) has also been postulated. Anaerobic bacteria are occasionally found in sponge tissue, though their contribution to sponge metabolism is completely unknown. There is increasing interest in biotechnological production of sponge biomass for sustainable use of this promising marine resource. Our studies will contribute to a thorough understanding of sponge-bacteria interaction, and form the basis for the development of biotechnological methods. Most research has been done on tropical and subtropical sponges. Participants of this project will apply, for the first time, microbiological and chemical studies on boreal sponges. Objectives: • Description of chemical conditions in sponge tissue: occurrence of microniches • Cultivation of specific groups of aerobic and anaerobic sponge associated bacteria • Establishment of novel methods for co-cultivation of sponge cells and bacteria • Identification of new bacterial biomarkers • Elucidation of connections between spatial distribution of associated bacteria and metabolites with a focus on anoxic zones and anaerobic microbial communities (especially sulfate reducing bacteria and Archaea) • Investigation of chemical communication and other interactions (´bacterial farming´) between sponge cells and bacteria as well as sponges and their environment