Research

Microbial Ecology – Lake Cadagno

Image Microbial Ecology – Lake Cadagno
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       The research is centred on the microbial ecology of the anoxygenic phototrophic sulfur bacteria living in the depth, water column (chemocline and monimolimnion) and in the sediments (microbial mats), of the meromictic Lake Cadagno. Especially in the oxic-anoxic transition zone, known as chemocline, the presence of light and hydrogen sulfide (H2S) promotes the development of an abundant community of anaerobic phototrophic sulfur bacteria. During summer, the concentration of microorganisms in the chemocline can reach values up to 107 cells per milliliter, which turns the water pink, an effect that is visible to the naked eye. Each bacterial population living in this ecological niche is subject to physical, chemical, and biological constraints  that imply survival and persistence strategies. Moreover, due to the photosynthetic activity of the anaerobic sulfurous bacteria of the chemocline (i.e. their particular role in the carbon cycle), Lake Cadagno can support much more fish biomass than other alpine lakes, which makes it very popular with fishermen. 
 
       The main objectives are the monitoring of the composition and the distribution of key anaerobical microbial species during the year and between the season (up to 20 years), as well as more physiological studies, in the laboratory (in vitro) and in the lake (in situ), increasing the knowledge on two key bio-geochemicals cycles such as sulfur and carbon cycles.

Nicola Storelli

Resistance to antibiotics in the environment

Image Resistance to antibiotics in the environment
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Bacteria resistant to antibiotics, both pathogenic and environmental, are present in the environment and contribute to increasing the "resistance", ie the set of all genes that determine resistance to antibiotics. We study, through the use of "model" microorganisms and molecular techniques, the spread of genes that confer resistance to antibiotics in freshwater environments located in anthropized areas, that is influenced by human activities of different types (eg. discharges from urban, hospital and industrial wastewater treatment plants).

 

Antonella Demarta and Federica Mauri

Ecology and biodiversity of aquatic fungi

Image Ecology and biodiversity of aquatic fungi
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Microscopic saprotrophic fungi of the group aquatic hyphomycetes carry out important processes in the ecosystems of forested streams. They drive the degradation of detritus, especially dry leaves, which are the main basal resource of the food webs in these streams. This field of research studies these processes, the importance of biodiversity, and their sensitivity to environmental change, including pollution and climate change. Projects in this research area use a combination of cultivation of aquatic hyphomycetes, their microscopic, molecular (DNA sequencing) and proteomic characterization (MALDI TOF MS), and quantification of biomarkers for estimates of biomass and enzyme expression.

Andreas Bruder

Conservation and restoration

Cristina Fragoso

Contacts
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