Extremely Radiation-Resistant Mutants of a Halophilic Archaeon with Increased Single-Stranded DNA-Binding Protein (RPA) Gene Expression

  title={Extremely Radiation-Resistant Mutants of a Halophilic Archaeon with Increased Single-Stranded DNA-Binding Protein (RPA) Gene Expression},
  author={Linda C DeVeaux and Jochen A. M{\"u}ller and Jonathon E. Smith and Jill E. Petrisko and D Wells and Shiladitya DasSarma},
  booktitle={Radiation research},
Abstract DeVeaux, L. C., Müller, J. A., Smith, J. R., Petrisko, J., Wells, D. P. and DasSarma, S. Extremely Radiation-Resistant Mutants of a Halophilic Archaeon with Increased Single-Stranded DNA-Binding Protein (RPA) Gene Expression. Radiat. Res. 168, 507–514 (2007). Extremely halophilic archaea are highly resistant to multiple stressors, including radiation, desiccation and salinity. To study the basis of stress resistance and determine the maximum tolerance to ionizing radiation, we exposed… 
Bioengineering radioresistance by overproduction of RPA, a mammalian-type single-stranded DNA-binding protein, in a halophilic archaeon
Results clearly establish that overexpression of haloarchaeal RPA promotes ionizing radiation resistance in Halobacterium sp.
Divergent Roles of RPA Homologs of the Model Archaeon Halobacterium salinarum in Survival of DNA Damage
The haloarchaea are unusual in possessing genes for multiple homologs to the ubiquitous single-stranded DNA binding protein (SSB or replication protein A, RPA) found in all three domains of life, and deletions in the five RPA operons are created, suggesting that the different RPA homologys have specialized roles depending on the type of genomic insult encountered.
Nucleotide fluctuation of radiation-resistant Halobacterium sp. NRC-1 single-stranded DNA-binding protein (RPA) genes
The Single-Stranded DNA-Binding Protein (RPA) Genes in gamma ray radiation-resistant halophilic archaeon Halobacterium sp. NRC-1 were analyzed in terms of their nucleotide fluctuations. In an ATCG
Acid Experimental Evolution of the Haloarchaeon Halobacterium sp. NRC-1 Selects Mutations Affecting Arginine Transport and Catabolism
In the haloarchaeon NRC-1, as in bacteria, pH adaptation was associated with genes involved in arginine catabolism and proton transport, and this study is among the first to report experimental evolution with multiple resequenced genomes of an archaeon.
Transcriptional profiling of the model Archaeon Halobacterium sp. NRC-1: responses to changes in salinity and temperature
BackgroundThe model halophile Halobacterium sp. NRC-1 was among the first Archaea to be completely sequenced and many post-genomic tools, including whole genome DNA microarrays are now being applied
Mechanisms of Resistance to Ionizing Radiation in Extremophiles
The role of mannosylglycerate, di-myo-inositol phosphate, and trehalose in the IR resistance of various thermophiles are examined and it is concluded the anaerobic environment confers their IR resistance.
DNA Replication and Repair in Halophiles
The natural environment inhabited by halophiles results in continual exposure of these organisms to elevated temperatures, fluctuations in oxygen and nutrient concentrations, high levels of solar
Polyploidy in Archaea and Bacteria: About Desiccation Resistance, Giant Cell Size, Long-Term Survival, Enforcement by a Eukaryotic Host and Additional Aspects
  • J. Soppa
  • Biology
    Journal of Molecular Microbiology and Biotechnology
  • 2014
The topics include possible laboratory artifacts, resistance against double-strand breaks, long-term survival, relaxation of DNA segregation and septum formation, enforced polyploidy by a eukaryotic host, genome equalization by gene conversion, and the nongenetic usage of genomic DNA as a phosphate storage polymer.
The Survival and Resistance of Halobacterium salinarum NRC-1, Halococcus hamelinensis, and Halococcus morrhuae to Simulated Outer Space Solar Radiation.
Overall, this study shows that some halophilic archaea are highly resistant to simulated solar radiation and that they are of high astrobiological significance.


Physiological responses of the halophilic archaeon Halobacterium sp. strain NRC1 to desiccation and gamma irradiation
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
UV irradiation induces homologous recombination genes in the model archaeon, Halobacterium sp. NRC-1
Results show that homologous recombination plays an important role in the cellular response of Halobacterium sp.
Genome sequence of Halobacterium species NRC-1.
Analysis of the genome sequence shows the presence of pathways for uptake and utilization of amino acids, active sodium-proton antiporter and potassium uptake systems, sophisticated photosensory and signal transduction pathways, and DNA replication, transcription, and translation systems resembling more complex eukaryotic organisms.
Understanding the adaptation of Halobacterium species NRC-1 to its extreme environment through computational analysis of its genome sequence.
The genome of the halophilic archaeon Halobacterium sp. NRC-1 and predicted proteome have been analyzed by computational methods and reveal characteristics relevant to life in an extreme environment
Systems level insights into the stress response to UV radiation in the halophilic archaeon Halobacterium NRC-1.
We report a remarkably high UV-radiation resistance in the extremely halophilic archaeon Halobacterium NRC-1 withstanding up to 110 J/m2 with no loss of viability. Gene knockout analysis in two
An Archaeal Chromosomal Autonomously Replicating Sequence Element from an Extreme Halophile, Halobacterium sp. Strain NRC-1
In halophilic archaea, a chromosomal origin of replication is physically linked to orc7 homologs and that this element is sufficient to promote autonomous replication, indicating that the finding of a functional haloarchaeal origin in relation to the large number of orc1-cdc6 homologys identified in the genomes of all halo archaea to date.
Genomic and genetic dissection of an archaeal regulon
Similarities of the bop-like UAS and transcription factors in diverse organisms, including a plant and a γ-proteobacterium, suggest an ancient origin for this regulon capable of coordinating light and oxygen responses in the three major branches of the evolutionary tree of life.
Radiation-Resistant Mutants of Salmonella typhimurium LT2: Development and Characterization
It is suggested that the observed increases in radioresistance result from a selection of mutations leading to an increased capacity to repair DNA.
Radiation sensitivity of N. pharaonis in comparison with E. coli K12 strains
It was found that N. pharaonis can tolerate a remarkably higher irradiation dose than the two E. coli strains and is probably related to the higher DNA repair ability of this archaebacteria strain.