Genomic analysis of facultatively oligotrophic haloarchaea of the genera Halarchaeum, Halorubrum, and Halolamina, isolated from solar salt.

Extremely halophilic archaea (haloarchaea) belonging to the phylum Euryarchaeota have been found in high-salinity environments. In this study, Halarchaeum sp. CBA1220, Halorubrum sp. CBA1229, and Halolamina sp. CBA1230, which are facultatively oligotrophic haloarchaea, were isolated from solar salt by culture under oligotrophic culture conditions. The complete genomes of strains CBA1220, CBA1229, and CBA1230 were sequenced and were found to contain 3,175,875, 3,582,278, and 3,465,332 bp, with a G + C content of 68.25, 67.66, and 66.75 mol %, respectively. In total, 60, 36, and 33 carbohydrate-active enzyme genes were determined in the respective strains. The strains harbored various genes encoding stress-tolerance proteins, including universal stress proteins, cold-shock proteins, and rubrerythrin and rubrerythrin-related proteins. The genome data produced in this study will facilitate further research to improve our understanding of other halophilic strains and promote their industrial application.