| Summary: | In the Polar Regions, Cyanobacteria are the key primary producers and main drivers of the food webs in a wide range of aquatic to terrestrial habitats. For example, they build benthic microbial mats in lakes and soil crusts. Their success in these harsh cold conditions can probably be explained by particular adaptations to survive freeze/thaw cycles, seasonally contrasted light intensities, high UV radiations, dessication and other environmental stresses. The BCCM/ULC public collection is funded by the Belgian Science Policy Office since 2011. It has obtained the ISO9001 certification for deposition and distribution of strains, as part of the multi-site certification for the BCCM consortium. This collection aims to gather a representative portion of the polar cyanobacterial diversity with different ecological origins (limnetic mats, soil crusts, cryoconites, endoliths,….) and make it available for researchers to study the taxonomy, evolution, adaptations to harsh environmental conditions, pigments, and genomic make-up. It presently includes 226 cyanobacterial strains, of which 119 are of Antarctic origin (catalogue: http://bccm.belspo.be/catalogues/ulc-catalogue-search). As shown by morphological identification, the strains belong to five orders (Synechococcales, Oscillatoriales, Pleurocapsales, Chroococcidiopsidales and Nostocales). The 16S rRNA and ITS sequences of the strains are being characterized. The first 85 Antarctic strains already studied are distributed into 25 Operational Taxonomic Units (OTUs = groups of sequences with > 97,5% 16S rRNA similarity), and thus, represent a quite large diversity. Moreover, strains identified as members of the genera Leptolyngbya or Phormidium appear in several lineages. This supports the idea that there is a need to revise the taxonomy of these polyphyletic genera with a simple filamentous morphology. To better understand the functioning, metabolism and adaptative strategies of cyanobacteria in the extreme Antarctic environment, the genome sequencing of 11 strains ...
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