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Mutagenesis in Bacterial Spores Exposed to Space and Simulated Martian Conditions: Data from the EXPOSE-E Spaceflight Experiment PROTECT

Moeller, Ralf and Reitz, Günther and Nicholson, Wayne L. and the PROTECT Team, * and Horneck, Gerda (2012) Mutagenesis in Bacterial Spores Exposed to Space and Simulated Martian Conditions: Data from the EXPOSE-E Spaceflight Experiment PROTECT. Astrobiology, 12 (5), pp. 457-468. Mary Ann Liebert, Inc.. DOI: 10.1089/ast.2011.0739.

Full text not available from this repository.

Abstract

As part of the PROTECT experiment of the EXPOSE-E mission on board the International Space Station (ISS), the mutagenic efficiency of space was studied in spores of Bacillus subtilis 168. After 1.5 years’ exposure to selected parameters of outer space or simulated martian conditions, the rates of induced mutations to rifampicin resistance (Rif^R) and sporulation deficiency (Spo⁻) were quantified. In all flight samples, both mutations, Rif^R and Spo⁻ , were induced and their rates increased by several orders of magnitude. Extraterrestrial solar UV radiation ( > 110 nm) as well as simulated martian UV radiation ( > 200 nm) led to the most pronounced increase (up to nearly 4 orders of magnitude); however, mutations were also induced in flight samples shielded from insolation, which were exposed to the same conditions except solar irradiation. Nucleotide sequencing located the Rif^R mutations in the rpoB gene encoding the β-subunit of RNA polymerase. Mutations isolated from flight and parallel mission ground reference (MGR) samples were exclusively localized to Cluster I. The 21 Rif^R mutations isolated from the flight experiment showed all a C to T transition and were all localized to one hotspot: H482Y. In mutants isolated from the MGR, the spectrum was wider with predicted amino acid changes at residues Q469K/L/R, H482D/P/R/Y, and S487L. The data show the unique mutagenic power of space and martian surface conditions as a consequence of DNA injuries induced by solar UV radiation and space vacuum or the low pressure of Mars.

Document Type:Article
Title:Mutagenesis in Bacterial Spores Exposed to Space and Simulated Martian Conditions: Data from the EXPOSE-E Spaceflight Experiment PROTECT
Authors:
AuthorsInstitution or Email of Authors
Moeller, Ralf Radiation Biology Department, Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany.
Reitz, Günther Radiation Biology Department, Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany.
Nicholson, Wayne L. Department of Microbiology and Cell Science, University of Florida, Space Life Sciences Laboratory, Kennedy Space Center, Florida, USA.
the PROTECT Team, *UNSPECIFIED
Horneck, GerdaRadiation Biology Department, Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany.
Date:2012
Journal or Publication Title:Astrobiology
Refereed publication:Yes
In SCOPUS:Yes
In ISI Web of Science:Yes
Volume:12
DOI:10.1089/ast.2011.0739
Page Range:pp. 457-468
Publisher:Mary Ann Liebert, Inc.
Status:Published
Keywords:Bacillus, Spores, Planetary protection, Space, Mars, Mutagenicity
HGF - Research field:Aeronautics, Space and Transport, Aeronautics, Space and Transport (old)
HGF - Program:Space, Space (old)
HGF - Program Themes:Research under Space Conditions, W FR - Forschung unter Weltraumbedingungen (old)
DLR - Research area:Raumfahrt, Space
DLR - Program:R FR - Forschung unter Weltraumbedingungen, W FR - Forschung unter Weltraumbedingungen
DLR - Research theme (Project):R - Vorhaben Strahlenbiologie, W - Vorhaben Strahlenbiologie (old)
Location: Köln-Porz
Institutes and Institutions:Institute of Aerospace Medicine > Radiation Biology
Deposited By: Kerstin Kopp
Deposited On:08 Aug 2012 15:36
Last Modified:20 Mar 2013 19:45

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