[O-08] Poster presentations by senior high school students

[O08-P29] Isolation and identification of Extreme Halophiles in worldwide rock salts with a specific carbon source

*Taichi Uchida¹ (1.Seiko Gakuin high school)

Keywords:rock salt, archaea, haloarchaea, astrobiology

To use the high salinity groundwater of Mars, using useful microorganisms that can grow in the same environment to Mars will be effective. Therefore, accessible rock salts derived from the high salinity environment on the earth are prepared to screen halophilic microorganisms that can withstand the high salinity environment like Mars and identify the species based on the genome sequence. Specifically, we prepared agar media with 20% salt concentration, having either D-glucose or L-glutamate as a single carbon source. Total 10 prepared rock salt solutions were inoculated on either plates and cultured them at room temperature. 42 days later, we confirmed colony formation on four media. 95 days later, we confirmed a new colony on one media. The colonies that grew on the medium were classified into 8 groups based on their color and shape and numbered from 1 to 8. The eight colonies were colony-picked and each was immersed in pure water in a microtube to extract genomic DNA. PCR was performed using 16SrDNA primers specific for Archaea and Bacteria, and all eight colonies were found to be of archaeal species. In addition, the PCR-amplified 16SrDNA fragments were subjected to sequencing, and analyzed with The Center for Microbial Ecology sequence database and The National Center for Biotechnology Information (NCBI) BLAST homology A homology search was performed. Phylogenetic tree analysis was also performed based on the sequences. Based on these results, we consider that 1, 4, 6, and 8 are likely to be in the genus Halobacterium, 7 in the genus Halachaeum, 3 in the genus Natrinema, 5 in the genus Halococcus, and 2 in the genus haloarcula.