Culturable Microbial Diversity in Microbial Mats of Saline Lakes on Christmas Island
In the frame of a DFG-funded project and in cooperation with the Geobiology Division of the University of Göttingen, an expedition to the saline lakes of Christmas Island (Republic of Kiribati, Central Pacific) took place in March 2011. Some of the saline lakes of this large atoll are of special interest because they are characterized by very thick gelatinous microbial mats that seem to control the precipitation of gypsum and carbonates at the bottom of the lakes. These habitats are composed mainly of cyanobacteria in the upper layers and anaerobic phototrophic bacteria in the deeper zones where the mineralization takes place. The function of the non-phototrophic microbial community is largely unknown, but it is thought that distinct types of Bacteria and Archaea play a major role in the precipitation of minerals.
Samples of these mats were brought to the DSMZ and are used for the selective enrichment of microorganisms displaying various metabolic types. The obtained results will lead to a better understanding of the formation of geological structures in earth history that are known as stromatolites.
SPRING, S., BRINKMANN, N., MURRJA, M., SPRÖER, C., REITNER, J., KLENK, H.-P. High diversity of culturable prokaryotes in a lithifying hypersaline microbial mat. Geomicrobiol. J. 32(3-4):332-346 (2015). doi:10.1080/01490451.2014.913095