Interface Ecology: How do macroalgae control the quantity and composition of bacterial epibioses at their surfaces?

• Applicant: Professor Martin Wahl, Ph.D.
• Subject Area: Microbial Ecology and Applied Microbiology
• Term: from 2008 to 2012
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 86566400

Epiphytic bacterial communities have the proven potential to profoundly modify the functional interface between macroalgae and their environment. Pilot studies strongly indicate that biofilms on cooccurring macroalgal species differ fundamentally even when they originate from the same colonizer pool. However, the specific composition of biofilms on different hosts or the algal capacity to control its biofilm is still largely unknown. The proposed research will fill this gap for three different macroalgae of great ecological and economical importance: Fucus vesiculosus, Gracilaria vermiculophylla, Ulva compressa. We aim to analyse specificity, structure and variability of biofilms on these macroalgae and the host’s chemical control over these biofilm characteristics. The epibacterial communities will be characterized by 16S rDNA analysis (degenerating gel gradient electrophoresis and sequencing) followed by sequencing. Using a novel technique which permits to simulate the continuous excretion process on algal surfaces, natural surface extracts of macroalgae will be tested for their capacity to control the formation, composition and dynamics of natural marine biofilms.

• DFG Programme: Research Grants