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

Extremophiles

Department of Cell Biology and Molecular Genetics, University of Maryland, 3221 H.J. Patterson Hall, College Park, MD 20742, USA.

Published: June 2005

We report that the halophilic archaeon Halobacterium sp. strain NRC-1 is highly resistant to desiccation, high vacuum and 60Co 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 60Co 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 Halobacterium sp. to that of the more radiation-sensitive Escherichia coli that grows in lower-salt conditions. No inducible response was observed after exposing Halobacterium 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.

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00792-005-0437-4DOI Listing

Publication Analysis

Top Keywords

gamma irradiation
24
high vacuum
12
kgy gamma
12
gamma
9
halophilic archaeon
8
archaeon halobacterium
8
halobacterium strain
8
desiccation gamma
8
vacuum 60co
8
60co gamma
8

Similar Publications

Fast-neutron reactors are an important representative of Generation IV nuclear reactors, and due to the unique structure and material properties of fast reactor fuel, traditional mechanical cutting methods are not applicable. In contrast, laser cutting has emerged as an ideal alternative. However, ensuring the stability of optical fibers and laser cutting heads under high radiation doses, as well as maintaining cutting quality after irradiation, remains a significant technical challenge.

View Article and Find Full Text PDF

Plants in space face unique challenges, including chronic ionizing radiation and reduced gravity, which affect their growth and functionality. Understanding these impacts is essential to determine the cultivation conditions and protective shielding needs in future space greenhouses. While certain doses of ionizing radiation may enhance crop yield and quality, providing "functional food" rich in bioactive compounds, to support astronaut health, the combined effects of radiation and reduced gravity are still unclear, with potential additive, synergistic, or antagonistic interactions.

View Article and Find Full Text PDF

This study investigates the negative impact of climate change on water resources, specifically water for agricultural irrigation. It describes how to optimize swelling, gel properties and long-term water retention capacities of Na-CMC/PAAm hydrogels for managing drought stress of Sugar beet plants through techniques such as changing the composition, synthetic conditions and chemical modification. Gamma radiation-induced free radical copolymerization was used to synthesize superabsorbent hydrogels using sodium carboxymethyl cellulose (Na-CMC) and acrylamide (AAm).

View Article and Find Full Text PDF

Cyberknife radio-neurosurgery for secreting pituitary adenomas treated with single fraction radio-neurosurgery: A systematic review and meta-analysis.

J Clin Neurosci

January 2025

Lausanne University Hospital (CHUV), Neurosurgery Service and Gamma Knife Center, Switzerland; University of Lausanne (UNIL), Faculty of Biology and Medicine (FBM), Switzerland; Ecole Polytechnique Fédérale de Lausanne (EPFL, LTS-5), Switzerland. Electronic address:

Introduction: Stereotactic radiosurgery (SRS) is one of the treatment options for the management of residual or recurrent secreting pituitary adenomas (PA). While the role of radiosurgery (RS) by Gamma Knife (GK) has been clearly established, Cyberknife (CK) RS has been evaluated in fewer series.

Material And Methods: To perform a systematic review of the literature and meta-analysis, with the aim of focusing on the effect of CK RS on secreting PA.

View Article and Find Full Text PDF

Stereotactic radiosurgery (SRS) and radiotherapy (SRT) have gained prominence as both adjuvant and primary treatment options for patients with skull base tumors that are either inoperable or present as residual or recurrent lesions post-surgery. The object of the current study is to evaluate the safety and efficacy of robotic-assisted SRS and SRT across various skull base pathologies. The study was conducted under PRISMA guidelines and involved a comprehensive evaluation of databases, including PubMed, Scopus, Embase, Web-of-Science, and the Cochrane Library.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!