Great Salt Lake (GSL) is home to halophiles, salt-tolerant Bacteria and Archaea, which live at 2-5M NaCl. In addition
to salt tolerance, GSL halophiles exhibit resistance to both ultraviolet (UV) irradiation and desiccation. First, to
understand desiccation resistance, we sought to determine the diversity of GSL halophiles capable of surviving
desiccation in either recently formed GSL halite crystals or GSL Artemia (brine shrimp) cysts. From these desiccated
environments, surviving microorganisms were cultured and isolated, and genomic DNA was extracted from the
individual species for identification by 16S rRNA gene homology. From the surface-sterilized cysts we also extracted
DNA of the whole microbial population for non-cultivation techniques. We amplified the archaeal or bacterial 16S
rRNA gene from all genomic DNA, cloned the cyst population amplicons, and sequenced. These sequences were
compared to gene databases for determination of closest matched species. Interestingly, the isolates from the crystal
dissolution are distinct from those previously isolated from GSL brine. The cyst population results reveal species not
found in crystals or brine, and may indicate microorganisms that live as endosymbionts of this hypersaline arthropod.
Second, we explored UV resistance in a GSL haloarchaea species, "H. salsolis." This strain resists UV irradiation an
order of magnitude better than control species, all of which have intact repair systems. To test the hypothesis that
halophiles have a photoprotection system, which prevents DNA damage from occurring, we designed an immunoassay
to detect thymine dimers following UV irradiation. "H. salsolis" showed remarkable resistance to dimer formation.
Evidence for both UV and desiccation resistance in these salt-tolerant GSL halophiles makes them well-suited as models
for Astrobiological studies in pursuit of questions about life beyond earth.