RRC ID 41256
著者 Leuko S, Domingos C, Parpart A, Reitz G, Rettberg P.
タイトル The Survival and Resistance of Halobacterium salinarum NRC-1, Halococcus hamelinensis, and Halococcus morrhuae to Simulated Outer Space Solar Radiation.
ジャーナル Astrobiology
Abstract UNLABELLED:Solar radiation is among the most prominent stress factors organisms face during space travel and possibly on other planets. Our analysis of three different halophilic archaea, namely Halobacterium salinarum NRC-1, Halococcus morrhuae, and Halococcus hamelinensis, which were exposed to simulated solar radiation in either dried or liquid state, showed tremendous differences in tolerance and survivability. We found that Hcc. hamelinensis is not able to withstand high fluences of simulated solar radiation compared to the other tested organisms. These results can be correlated to significant differences in genomic integrity following exposure, as visualized by random amplified polymorphic DNA (RAPD)-PCR. In contrast to the other two tested strains, Hcc. hamelinensis accumulates compatible solutes such as trehalose for osmoprotection. The addition of 100 mM trehalose to the growth medium of Hcc. hamelinensis improved its survivability following exposure. Exposure of cells in liquid at different temperatures suggests that Hbt. salinarum NRC-1 is actively repairing cellular and DNA damage during exposure, whereas Hcc. morrhuae exhibits no difference in survival. For Hcc. morrhuae, the high resistance against simulated solar radiation may be explained with the formation of cell clusters. Our experiments showed that these clusters shield cells on the inside against simulated solar radiation, which results in better survival rates at higher fluences when compared to Hbt. salinarum NRC-1 and Hcc. hamelinensis. Overall, this study shows that some halophilic archaea are highly resistant to simulated solar radiation and that they are of high astrobiological significance.
KEY WORDS:Halophiles-Solar radiation-Stress resistance-Survival.
巻・号 15(11)
ページ 987-97
公開日 2015-11-1
DOI 10.1089/ast.2015.1310
PMID 26539978
MeSH Extraterrestrial Environment* Halobacterium salinarum / radiation effects* Halococcus / classification Halococcus / radiation effects* Models, Biological* Species Specificity Sunlight*
IF 4.28
引用数 16
WOS 分野 GEOSCIENCES, MULTIDISCIPLINARY BIOLOGY ASTRONOMY & ASTROPHYSICS
リソース情報
一般微生物 JCM 12892