Antarctic Marine Microbial Diversity: a Promising Source of Novel Enzymes and Bioactive Molecules

Microorganisms are considered among the most valuable sources of new molecules with biotechnological potential, such as enzymes or bioactive compounds. In recent years, research shifted towards exploring unconventional ecological niches, such as extreme environments, where the local microorganisms need to develop unique strategies to withstand the harsh environmental conditions. As a part of the ANT-Biofilm project (PNRA16_00105-A1), we recently studied marine biofilm samples, collected from poly-vinyl-chloride panels, submerged at -5 m for two or twelve months in two locations (Road Bay and Punta Stocchino) in Terra Nova Bay (Antarctica). Preliminary metagenomic analyses on biofilm microbial community composition revealed Proteobacteria as the dominant phylum (49-87%), followed by Actinobacteria (4-32%), Bacteroidetes (6-27%) and Verrucomicrobia (0.5-12%). Up to 384 different culture conditions were consequently applied, and after morphological dereplication, 93 strains were recovered from the biofilm samples, comprising 66 unicellular bacteria, 19 filamentous actinomycetes and 8 filamentous fungi, along with 40 other bacteria isolated from seawater.