Abstract :
[en] The BCCM/ULC public collection funded by the Belgian Science Policy Office since 2011 aims
to gather a representative portion of terrestrial, freshwater and marine cyanobacterial strains
with a focus on the polar diversity with different ecological origins (limnetic mats, soil crusts,
cryoconites, endoliths…).
The collection’s aim is to preserve the deposited biological material, to valorize it by performing
research on it, to provide it to interested parties for fundamental and applied research,
and to provide services linked to the identification of the Cyanobacteria for the scientific
community. An ISO 9001 certificate was obtained for the public deposition and distribution of
strains, as part of the multi-site certification for the BCCM consortium.
Currently, the ULC collection contains 253 cyanobacterial strains, with 134 being of Polar origin
and 8 from soda lakes. Cyanobacteria in the Polar Regions represent key primary producers
and are the main drivers of the food webs in a wide range of aquatic to terrestrial habitats.
Also in soda lakes, despite their extreme haloalkaliphilic conditions, the primary production
is very high and partially originates from the cyanobacterial communities. Due to their harsh
environments, all these extremophilic Cyanobacteria may present interesting features to
survive, for example, freeze/thaw cycles, fluctuating salt concentrations, high UV radiations,
desiccation and other stresses. Morphological identification shows that the strains of BCCM/
ULC belong to the orders Synechococcales, Oscillatoriales, Pleurocapsales, Chroococcidiopsidales
and Nostocales. The 189 BCCM/ULC strains, for which 16S rRNA sequences were
analyzed correspond to 69 OTUs (sequences with > 99 % 16S rRNA similarity), representing a
large diversity.
Recently, the novel genus and species Sodalinema komarekii has been isolated from the
tropical soda lake Dziani Dzaha (Mayotte, Indian Ocean) (Cellamare et al., 2018). Three yet
undescribed representatives of this genus have been detected in the collection (ULC137, 138,
139), which, however, originate from Siberian soda lakes and thus live in very different climate
conditions. Further studies will reveal their phylogenetic relation to the newly described
genus and species.
