TY - JOUR
T1 - Whole metagenome profiles of particulates collected from the International Space Station
AU - Be, Nicholas A.
AU - Avila-Herrera, Aram
AU - Allen, Jonathan E.
AU - Singh, Nitin
AU - Checinska Sielaff, Aleksandra
AU - Jaing, Crystal
AU - Venkateswaran, Kasthuri
N1 - Funding Information:
This research was funded by a 2012 Space Biology NNH12ZTT001N grant no. 19-12829-26 under Task Order NNN13D111T award to KV which also funded post-doctoral fellowship for AC and a JPL subcontract 1506453 to GEF. This work was performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. In addition, the research carried out at the Lawrence Livermore National Laboratory was funded by a 2014 Space Biology NNH14ZTT002N grant no. NNX15AJ29G award to CJ which also funded JA, NB, and AAH.
PY - 2017/7/17
Y1 - 2017/7/17
N2 - BACKGROUND: The built environment of the International Space Station (ISS) is a highly specialized space in terms of both physical characteristics and habitation requirements. It is unique with respect to conditions of microgravity, exposure to space radiation, and increased carbon dioxide concentrations. Additionally, astronauts inhabit a large proportion of this environment. The microbial composition of ISS particulates has been reported; however, its functional genomics, which are pertinent due to potential impact of its constituents on human health and operational mission success, are not yet characterized.METHODS: This study examined the whole metagenome of ISS microbes at both species- and gene-level resolution. Air filter and dust samples from the ISS were analyzed and compared to samples collected in a terrestrial cleanroom environment. Furthermore, metagenome mining was carried out to characterize dominant, virulent, and novel microorganisms. The whole genome sequences of select cultivable strains isolated from these samples were extracted from the metagenome and compared.RESULTS: Species-level composition in the ISS was found to be largely dominated by Corynebacterium ihumii GD7, with overall microbial diversity being lower in the ISS relative to the cleanroom samples. When examining detection of microbial genes relevant to human health such as antimicrobial resistance and virulence genes, it was found that a larger number of relevant gene categories were observed in the ISS relative to the cleanroom. Strain-level cross-sample comparisons were made for Corynebacterium, Bacillus, and Aspergillus showing possible distinctions in the dominant strain between samples.CONCLUSION: Species-level analyses demonstrated distinct differences between the ISS and cleanroom samples, indicating that the cleanroom population is not necessarily reflective of space habitation environments. The overall population of viable microorganisms and the functional diversity inherent to this unique closed environment are of critical interest with respect to future space habitation. Observations and studies such as these will be important to evaluating the conditions required for long-term health of human occupants in such environments.
AB - BACKGROUND: The built environment of the International Space Station (ISS) is a highly specialized space in terms of both physical characteristics and habitation requirements. It is unique with respect to conditions of microgravity, exposure to space radiation, and increased carbon dioxide concentrations. Additionally, astronauts inhabit a large proportion of this environment. The microbial composition of ISS particulates has been reported; however, its functional genomics, which are pertinent due to potential impact of its constituents on human health and operational mission success, are not yet characterized.METHODS: This study examined the whole metagenome of ISS microbes at both species- and gene-level resolution. Air filter and dust samples from the ISS were analyzed and compared to samples collected in a terrestrial cleanroom environment. Furthermore, metagenome mining was carried out to characterize dominant, virulent, and novel microorganisms. The whole genome sequences of select cultivable strains isolated from these samples were extracted from the metagenome and compared.RESULTS: Species-level composition in the ISS was found to be largely dominated by Corynebacterium ihumii GD7, with overall microbial diversity being lower in the ISS relative to the cleanroom samples. When examining detection of microbial genes relevant to human health such as antimicrobial resistance and virulence genes, it was found that a larger number of relevant gene categories were observed in the ISS relative to the cleanroom. Strain-level cross-sample comparisons were made for Corynebacterium, Bacillus, and Aspergillus showing possible distinctions in the dominant strain between samples.CONCLUSION: Species-level analyses demonstrated distinct differences between the ISS and cleanroom samples, indicating that the cleanroom population is not necessarily reflective of space habitation environments. The overall population of viable microorganisms and the functional diversity inherent to this unique closed environment are of critical interest with respect to future space habitation. Observations and studies such as these will be important to evaluating the conditions required for long-term health of human occupants in such environments.
KW - Built environment
KW - Cleanroom
KW - Functional metagenomics
KW - International Space Station
KW - Microbiome
KW - Propidium monoazide
UR - http://www.scopus.com/inward/record.url?scp=85043231247&partnerID=8YFLogxK
U2 - 10.1186/s40168-017-0292-4
DO - 10.1186/s40168-017-0292-4
M3 - Article
C2 - 28716113
AN - SCOPUS:85043231247
SN - 2049-2618
VL - 5
SP - 81
JO - Microbiome
JF - Microbiome
IS - 1
ER -