Crewmember microbiome may influence microbial composition of ISS habitable surfaces

PLoS One. 2020 Apr 29;15(4):e0231838. doi: 10.1371/journal.pone.0231838. eCollection 2020.

Abstract

The International Space Station (ISS) is a complex built environment physically isolated from Earth. Assessing the interplay between the microbial community of the ISS and its crew is important for preventing biomedical and structural complications for long term human spaceflight missions. In this study, we describe one crewmember's microbial profile from body swabs of mouth, nose, ear, skin and saliva that were collected at eight different time points pre-, during and post-flight. Additionally, environmental surface samples from eight different habitable locations in the ISS were collected from two flights. Environmental samples from one flight were collected by the crewmember and samples from the next flight were collected after the crewmember departed. The microbial composition in both environment and crewmember samples was measured using shotgun metagenomic sequencing and processed using the Livermore Metagenomics Analysis Toolkit. Ordination of sample to sample distances showed that of the eight crew body sites analyzed, skin, nostril, and ear samples are more similar in microbial composition to the ISS surfaces than mouth and saliva samples; and that the microbial composition of the crewmember's skin samples are more closely related to the ISS surface samples collected by the crewmember on the same flight than ISS surface samples collected by other crewmembers on different flights. In these collections, species alpha diversity in saliva samples appears to decrease during flight and rebound after returning to Earth. This is the first study to compare the ISS microbiome to a crewmember's microbiome via shotgun metagenomic sequencing. We observed that the microbiome of the surfaces inside the ISS resemble those of the crew's skin. These data support future crew and ISS microbial surveillance efforts and the design of preventive measures to maintain crew habitat onboard spacecraft destined for long term space travel.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Astronauts*
  • DNA, Bacterial / genetics
  • DNA, Bacterial / isolation & purification
  • Ecological Systems, Closed*
  • Environmental Monitoring / methods
  • Humans
  • Metagenome / genetics
  • Microbiota / genetics*
  • Saliva / microbiology
  • Skin / microbiology
  • Space Flight / instrumentation*
  • Spacecraft*
  • Time Factors

Substances

  • DNA, Bacterial

Grants and funding

Aram Avila-Herrera, James Thissen, Nicholas A Be, Crystal Jaing were funded by NASA Space Biology under contract #: 80NSSC18K0113. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Camilla Urbaniak and Kasthuri Venkateswaran were funded by NASA Space Biology Task Plan #47-700062. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Satish Mehta were funded by NASA Space Biology under contract #: 80NSSC18K0113. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. David J Smith was funded by NASA Ames Space Biology program. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Fathi Karouia was supported through the KBRwyle/FILMSS subcontract with the Department of Pharmaceutical Chemistry at the University of California San Francisco, # NNA14AB82C, at NASA Ames Research Center. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.