300552 VO Physiology and Ecology of Cyanobacteria (2007W)

Cyanobacteria occur all over the world and colonize freshwater and marine systems, hot springs, and terrestrial habitats. They dominate in benthic communities in the littoral zone of aquatic systems as well as in the pelagic zone of freshwater systems and the oceans. Cyanobacteria fascinate by their physiological adaptations and their metabolic diversity, for example through the production of toxic and bioactive compounds. This lecture will introduce into the physiological properties of cyanobacteria and their ecology in aquatic and terrestrial ecosystems. The ecological role of the production of bioactive compounds and the consequences for humans will be discussed.
The lecture is structured into 7 parts:
1) General characteristics of cyanobacteria (Morphology, cell organelles, motility, pigments, gas vesicles, storage products, resting stages, hormogonia, heterocytes, taxonomy and phylogenetic characteristics)
2) Diversity of life forms, planktonic, benthic (semi-arid), epilithic, including special physiological adaptations: strength of gas vesicles, colony formation and mucilage production, vertical migration in the water column, grazing resistance, growth rates, energy budget, nutrient competition, nutrient storage
3) Nitrogen fixation (nitrogenase, physiological factors regulating the formation of heterocytes, N-fixation outside heterocytes, ecology of N-fixation)
4) Toxic and bioactive compounds (peptides, alkaloids, synthesis pathways, ecological role of bioactive compounds, allelopathy, feeding deterrence, role of toxins in the food web and transport via the food chain, deterioration of water quality, pharmacological relevance)
5) Pigments of cyanobacteria and living in extreme environments (Scytonemin, mycosporine-like amino acids, etc.), carotenoids and biosynthesis, phycobilins, adaptations to extreme chemical (H2S, heavy metals) and physical conditions (low - high temperature)
6) Extracellular polysaccharides, chemical composition, ecological role (protection against viruses, osmotic stress, heavy metals, grazing resistance), technical applications
7) Cyanobacteria in various ecosystems (Contribution to primary production, colonizing extreme habitats and role in the history of the earth, cyanobacteria as architects in benthic habitats, cyanobacteria and human nutrition, nitrogen-fixation, algal blooms), biogeography and associations of cyanobacteria in ecosystems