Summary
Low temperatures represent a critical factor in the survival of cold-adapted organisms via its indirect impact on organisms as well as through its influence on other environmental parameters: water availability, elevated salt concentrations, inaccessibility of organic and inorganic nutrients. Bacteria colonizing cold environments, commonly referred as psychrophiles, have developed unusual characteristics that allow them to thrive in their extreme niches. Since polar regions are more strongly impacted by global changes than temperate regions, there is an urgent need to understand how these perturbations will affect on microbial functions. All the cold niches offer an ideal variety of habitats to investigate changes in the composition and functionality of polar microbes, who may be true sentinels of the rapid global warming.

Objectives
The goal of this project is the study of the role and the structure of carbohydrate polymers from Antarctic marine bacteria in cold environments life-style and how temperature fluctuations can modify their structures. LPS and EPS structures of bacteria belonging to one selected strain among the genera Shewanella, Colwellia, Psychrobacter, and Pseudoalteromonas from Antarctic sponges will be structurally characterised by advanced chemical techniques, and their biological activity investigated in vitro. Results obtained from cells grown in temperature ranges of 0-4°C and 15-20°C will be compared to evaluate any differences related to the temperature enhancement. In addition, LPS and EPS molecules from one of the most interesting sea-ice model strains, C. psychrerythraea 34H, will be characterized and tested at -2°C and 15°C.

Project Partners
• Università di Napoli Federico II