Cyanobacterial diversity in the algal-bacterial consortia from Subarctic regions: new insights from the rock baths at White Sea Coast

Cyanobacteria characterized by exceptional tolerance to environmental stresses often become pioneer settlers in habitats with harsh conditions. There, they can constitute the core of microbial communities. The taxonomic composition of the cyanobacterial component of algal-bacterial consortia dwelling in a habitat with particularly harsh conditions (rock baths at the coast of Kandalaksha Bay of the White Sea) has been elucidated for the first time. Two workflows of the taxonomic analysis of the cyanobacteria were tested including the combinations of two programs and two databases (QIIME+Greengenes and Usearch+NCBI GenBank). Our results obviated the need of the using of a complex approach combining morphological and metagenomic analyses for revealing the taxonomic structure of cyanobacteria in natural habitats. Our results show that the cyanobacterial component of the consortia from the habitats with harsh and highly volatile environmental conditions is enriched with non-diazotrophic and diazotrophic non-branched filamentous cyanobacteria.