Acidic hypersaline lakes are found naturally only in Australia and Chile. These environments have been described as harboring one of the most biologically challenging waters found on Earth; however, they are relatively understudied. The relatively small number of microbes currently isolated that have the capacity to simultaneously tolerate both acidic and saline conditions reflects the rarity of acid saline environments worldwide.
The Yilgarn Craton in Western Australia contains hundreds of ephemeral hypersaline lakes many of which are highly acidic. These lakes are rare ecological niches that harbor microorganisms with the potential for unique biotechnological applications such as bioleaching of sulfide ores under saline conditions. This study aimed to explore the microbial ecology of eight acidic saline lakes from the Yilgarn Craton with varying levels of salinity and pH below 4.
The microbial ecology of water, soil and salt brine samples collected from these lakes varied considerably in their diversity and abundances of microbial communities. A large amount of ASVs in this study could not be assigned taxonomic rankings to family level, highlighting the amount of unknown microbial life in these extreme environments. However, the most dominate bacterial family identified in the lakes sediments was Acidithiobacillaceae, a well-known acidophilic iron and sulfur oxidizing family, thus demonstrating the potential of these environments for bioprospecting for haloacidophillic iron/sulfur oxidising microbes. The microbial ecology and diversity in these extreme acidic saline lakes will provide insight into: the functioning and evolution of dual acid and salt tolerance, the composition of microbial populations in acidic saline environments and how they function; and the potential biotechnological/industrial applications of haloacidophiles.