Conservation of Antarctica’s unique and underexplored microbial biodiversity

A project undertaken at the School of Biotechnology and Biomolecular Sciences, University of New South Wales and supervised by Belinda Ferrari

Project team: Belinda Ferrari, Mark Brown and John Kalaitzis; School of Biotechnology and Biomolecular Sciences, UNSW Australia;

Cold polar desert areas of Antarctica are among the harshest, driest, most extreme environments on earth but their ecology and biodiversity remains largely under-explored. Soils in Eastern Antarctica are very low in carbon, water and nutrient levels, and in most cases are devoid of plant and animal life. Thus, microbes form the majority of biomass and consequently drive ecosystem processes. The project “Conservation of Antarctica’s unique and underexplored microbial biodiversity, is part of an ongoing collaboration with the Australian Antarctic Division designed to develop an Australian polar culture collection and reveal, for the first time, the microbial phylogenetic and functional diversity of these regions. The work is being carried out in the cold desert soils of the Windmill Islands region, south of Australia’s Antarctic base at Casey Station. Using high-throughput, next generation DNA sequencing methods, we recently discovered that unprecedented levels of highly novel, potentially endemic bacteria thrive in these soils, and their functional capabilities are completely unknown.

This finding supports our hypothesis that the so-called “extreme” environments on Earth provide challenges to life that have directed the evolution of microorganisms with unique physiologies. Hence our aim is to not only discover new species, but to characterize the novel chemical compounds they produce. To do this we will specifically target chemical biosynthesis gene diversity. That is, those genes responsible for secondary metabolites or production of bioactive compounds. The most significant aspect of this study will be a greater understanding of the role that the production of these bioactive compounds play in the evolution and ecology of polar soil microorganisms.

An ultimate outcome of this project will be a polar soil microbiology culture collection and small chemical library of purified compounds. The knowledge we generate about microbial ecology and distributions will be used to assess the future effects of environmental change on these pristine environments and identify biodiversity “hotspots” that require specific environmental protection. Our discoveries will inform both policy makers and the wider community about the need for even the smallest inhabitants to be considered in Antarctic conservation efforts.

Figure 1. Browning Peninsula, Windmill Islands, Eastern Antarctica. Image thanks to Ian Snape of the Australian Antarctic Division

Figure 2. A close-up of Antarctica’s dry polar desert soils containing a plethora of unusual microbial life. Image thanks to Ian Snape of the Australian Antarctic Division

Figure 3. An antimicrobial-producing Streptomyces species, cultured from Browning Peninsula soil. Image by Nicole Benaud, UNSW Australia PhD candidate