A snapshot of microbial communities from the Kutch: one of the largest salt deserts in the World.

Here we present the first report on the taxonomic diversity of the microbial communities of the saline desert of the Great Rann of Kutch, Gujarat, India, using a metagenomic approach. Seven samples, differing in salinity levels and covering different seasons, were analysed to investigate the dynamics of microbial communities in relation to salinity and season. Metagenomic data generated using whole metagenome sequencing revealed that despite its very high salinity (4.11-30.79 %), the saline desert's microbiota had a rich microbial diversity that included all major phyla. Notably, 67 archaeal genera, representing more than 60 % of all known archaeal genera, were present in this ecosystem. A strong positive correlation (0.85) was observed between the presence of the extremely halophilic bacterium Salinibacter and salinity level. Taxonomic and functional comparisons of the saline desert metagenome with those of other publicly available metagenomes (i.e. sea, hypersaline lagoon, solar saltern, brine, hot desert) was carried out. The microbial community of the Kutch was found to be unique yet more similar to the sea biomes followed by hypersaline lagoon.