Halophilic microbial communities and their environments

• High-throughput sequencing has improved our understanding of salt lake microbiology.
• Many abundant lineages of halophilic prokaryotes have not yet been isolated in culture.
• Some halophilic prokaryotes can degrade a surprisingly broad range of substrates.

Use of culture-independent studies have greatly increased our understanding of the microbiology of hypersaline lakes (the Dead Sea, Great Salt Lake) and saltern ponds in recent years. Exciting new information has become available on the microbial processes in Antarctic lakes and in deep-sea brines. These studies led to the recognition of many new lineages of microorganisms not yet available for study in culture, and their cultivation in the laboratory is now a major challenge. Studies of the metabolic potentials of different halophilic microorganisms, Archaea as well as Bacteria, shed light on the possibilities and the limitations of life at high salt concentrations, and also show their potential for applications in bioremediation.

Examples of hypersaline environments discussed in this review: a saltern crystallizer pond colored red by dense communities of Archaea and Dunaliella cells (upper left panel), sunrise over the Dead Sea (upper right panel), and a benthic microbial mat dominated by the cyanobacterium Coleofasciculus chthonoplastes (Sečovlje, Slovenia; lower panel). Photographs by the author.Figure optionsDownload high-quality image (163 K)Download as PowerPoint slide