Julia Kleinteich (Universität Tübingen, Germany) applied for Antarctic Science bursary funding in 2012, for a laboratory-based DNA sequencing funds to extend her PhD work on cyanobacterial mat diversity in the Antarctic (Kleinteich et al., 2012). There is little known about the diversity and physiology of cyanobacteria in the melt-water ecosystems of the polar reigons. In order to assess the species diversity of cyanobacterial mats, she proposed to conduct pyrosequencing to identify the cyanobacteria present in different mats, using samples collected from from Adelaide Island, Antarctica in 2010/2011. Sequencing of these extracts was conducted using the universal gene 16S to determine cyanobacterial diversity, with 274 operational taxonomic units (OTUs, or distinct ‘strains’) detected.
Species richness ranged between 8 and 33 cyanobacterial OTUs per sample, reflecting a high mat diversity. Leptolyngbya and Phormidium (c. 55% and 37% of the OTUs per mat) were dominant. Cyanobacterial community composition was similar between mats, particularly those obtained from closely adjacent locations. Julia found that cyanobacterial sample composition varied according to multiple environmental factors, with ten OTUs and the two most dominant cyanobacterial families correlated with mat colour. Three families were significantly associated with different habitat substrates. Cyanobacterial Shannon types were positively associated with higher temperatures. Many unidentified species were also sequenced, as only 3.2% of OTU types could be identified to species. This study demonstrated the usefulness of pyrosequencing for characterizing diverse cyanobacterial communities, providing useful insights into species association with different habitats and temperatures in the region.
This work was published in Antarctic Science in 2014 (Kleinteich et al., 2014).
Kleinteich J., Hildebrand F., Wood S.A., et al. (2014) Diversity of toxin and non-toxin containing cyanobacterial mats of meltwater ponds on the Antarctic Peninsula: a pyrosequencing approach. Antarct. Sci. 26, 521-532.
Kleinteich J., Wood S.A., Kupper F.C., Camacho A., Quesada A., Frickey T., Dietrich D.R. (2012) Temperature-related changes in polar cyanobacterial mat diversity and toxin production. Nat Clim Change 2, 356-360.