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Bacillus subtilis spores PROTECT experiment Space-exposed and Mars-exposed vs. Earth-control

Metadata Updated: December 6, 2023

Because of their ubiquity and resistance to spacecraft decontamination bacterial spores are considered likely potential forward contaminants on robotic missions to Mars. Thus it is important to understand their global responses to long-term exposure to space or Mars environments. As part of the PROTECT experiment spores of B. subtilis 168 were exposed to real space conditions and to simulated martian conditions for 559 days in low Earth orbit mounted on the EXPOSE-E exposure platform outside the European Columbus module on the International Space Station. Upon return spores were germinated total RNA extracted and fluorescently labeled and used to probe a custom Bacillus subtilis microarray to identify genes preferentially activated or repressed relative to ground control spores. Increased transcript levels were detected for a number of stress-related regulons responding to DNA damage (SOS response SP-beta prophage induction) protein damage (CtsR/Clp system) oxidative stress (PerR regulon) and cell envelope stress (SigV regulon). Spores exposed to space demonstrated a much broader and more severe stress response than spores exposed to simulated Mars conditions. The results are discussed in the context of planetary protection for a hypothetical journey of potential forward contaminant spores from Earth to Mars and their subsequent residence on Mars. Two-color microarrays were performed comparing germination of Space-exposed or Mars-exposed vs. ground-control (Earth) spores.

Access & Use Information

Public: This dataset is intended for public access and use. License: us-pd

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Metadata Created Date January 31, 2023
Metadata Updated Date December 6, 2023
Data Update Frequency irregular

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date January 31, 2023
Metadata Updated Date December 6, 2023
Publisher National Aeronautics and Space Administration
Identifier nasa_genelab_GLDS-28_h3sa-69gh
Data First Published 2021-05-21
Data Last Modified 2023-01-26
Category Earth Science
Public Access Level public
Data Update Frequency irregular
Bureau Code 026:00
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id a51a1f63-6b10-4c11-ab30-4c95d8a4e247
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL
Program Code 026:005
Source Datajson Identifier True
Source Hash 8bb8dd2145ec0cfbb4d3d2e13279f4c28b4e81576ecdb124636d418b2aeaa17e
Source Schema Version 1.1

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