Service interruption on Monday 11 July from 12:30 to 13:00: all the sites of the CCSD (HAL, Epiciences, SciencesConf, AureHAL) will be inaccessible (network hardware connection).
Skip to Main content Skip to Navigation
Journal articles

Physiological responses of the halophilic archaeon Halobacterium sp. strain NRC1 to desiccation and gamma irradiation

Abstract : We report that the halophilic archaeon Halo-bacterium sp. strain NRC-1 is highly resistant to desiccation , high vacuum and 60 Co gamma irradiation. Halobacterium sp. was able to repair extensive double strand DNA breaks (DSBs) in its genomic DNA, produced both by desiccation and by gamma irradiation, within hours of damage induction. We propose that resistance to high vacuum and 60 Co gamma irradiation is a consequence of its adaptation to desiccating conditions. Gamma resistance in Halobacterium sp. was dependent on growth stage with cultures in earlier stages exhibiting higher resistance. Membrane pigments, specifically bacterioruberin, offered protection against cellular damages induced by high doses (5 kGy) of gamma irradiation. High-salt conditions were found to create a protective environment against gamma irradiation in vivo by comparing the amount of DSBs induced by ionizing radiation in the chromosomal DNA of Halo-bacterium sp. to that of the more radiation-sensitive Escherichia coli that grows in lower-salt conditions. No inducible response was observed after exposing Halo-bacterium sp. to a nonlethal dose (0.5 kGy) of gamma ray and subsequently exposing the cells to either a high dose (5 kGy) of gamma ray or desiccating conditions. We find that the hypersaline environment in which Halobacterium sp. flourishes is a fundamental factor for its resistance to desiccation, damaging radiation and high vacuum.
Complete list of metadata
Contributor : Adrienne KISH Connect in order to contact the contributor
Submitted on : Tuesday, November 17, 2020 - 1:32:33 PM
Last modification on : Sunday, June 26, 2022 - 9:54:52 AM
Long-term archiving on: : Thursday, February 18, 2021 - 7:23:54 PM


2005_Kottemann_Kish_NRC1 physi...
Explicit agreement for this submission




Molly Kottemann, Adrienne Kish, Chika Iloanusi, Sarah Bjork, Jocelyne Diruggiero. Physiological responses of the halophilic archaeon Halobacterium sp. strain NRC1 to desiccation and gamma irradiation. Extremophiles, Springer Verlag, 2005, 9 (3), pp.219-227. ⟨10.1007/s00792-005-0437-4⟩. ⟨mnhn-02862359⟩



Record views


Files downloads