Microbial Tracking Payload Series (Microbial Observatory-1) - 01.16.19

Overview | Description | Applications | Operations | Results | Publications | Imagery

ISS Science for Everyone

Science Objectives for Everyone
Along with orbital crew members and experimental payloads, the International Space Station (ISS) is home to a variety of microbes, which can threaten crew health and jeopardize equipment. The Microbial Payload Tracking Series (Microbial Observatory-1) investigation monitors the types of microbes present on ISS over a one-year period. Samples are returned to Earth for further study, enabling scientists to understand the diversity of the microbial flora on the ISS and how it changes over time.
Science Results for Everyone
Microorganisms have always stowed away on spacecraft. As missions grow longer, the potential consequences of these uninvited passengers increase. Two fungal strains cultured in space and on Earth showed no significant difference between growth characteristics, metabolism, and susceptibility to chemical agents, suggesting fungi successfully adapt to space living. However, space strains appear more lethal to zebrafish larvae. Genetic sequencing of 20 moderately hazardous bacterial strains isolated from the space station allowed comparison to their Earth duplicates to determine microgravity’s influence on toxicity. Overall, space bacteria show increased resistance to antibiotics, affirming need for additional studies.

The following content was provided by Fathi Karouia, and is maintained in a database by the ISS Program Science Office.
Experiment Details

OpNom: Microbial Observatory-1

Principal Investigator(s)
Kasthuri Venkateswaran, Ph.D., California Institute of Technology, Pasadena, CA, United States

George E. Fox, Ph.D., University of Houston, Houston, TX, United States
Duane L. Pierson, Ph.D., NASA Johnson Space Center, Houston, TX, United States
Douglas Botkin, Ph.D., NASA JSC, Houston, TX, United States

NASA Ames Research Center, Moffett Field, CA, United States

Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)

Sponsoring Organization
NASA Research Office - Space Life and Physical Sciences (NASA Research-SLPS)

Research Benefits
Earth Benefits, Scientific Discovery, Space Exploration

ISS Expedition Duration
September 2014 - September 2015; March 2016 - September 2016

Expeditions Assigned

Previous Missions
Information Pending

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Experiment Description

Research Overview

  • For the Microbial Payload Tracking Series (Microbial Observatory-1) investigation, identification of the microbial diversity on ISS enables:
    • understanding risk to crew health in a closed environment for infection and illness.
    • understanding risk to fouling of clean air supplies and contamination of fluids and food.
    • understanding the similarities and differences between microbial communities on ISS and on Earth in nominal and extreme environments.
    • identifying which microbes flourish in the spaceflight and microgravity environment, which is important from a crew health perspective based on the published findings that pathogenic bacteria become more virulent in this environment.
    • studies into how microbes adapt to the microgravity and spaceflight extreme environment, which may provide insight in to individual and community adaptation to environmental changes.


As recommended by the National Research Council Decadal Survey, the Jet Propulsion Laboratory (JPL) proposes to establish an International Space Station–Microbial Observatory (ISS-MO) to generate a microbial census of the space station’s surfaces and atmosphere using advanced molecular microbial community analysis techniques, supported by traditional culture-based methods and modern bioinformatics computational modeling.
The proposed ISS-MO establishment leads into a long-term, multigenerational study of microbial population dynamics. The ISS-MO project’s methodology serves as the foundation for an extensive microbial census, offering significant insight into spaceflight-induced changes in the populations of beneficial and potentially harmful microbes. Additionally, it provides NASA with both a mechanistic understanding of these changes (e.g., cataloging population changes and mapping/linking these to environmental niche and genomic changes), as well as insight into practical countermeasures for mitigating risks to humans and environmental systems. The ISS-MO team uses existing ISS sample collection technologies to generate an initial microbial census. Following their return to Earth, samples from the various ISS modules are analyzed using standardized technologies from the Mars Program-funded projects.
The proposed ISS-MO project includes the delivery of a database that compiles the genomic sequences and genetic information for all the microbes encountered within the ISS habitat. Using this data, NASA can more accurately and confidently assess the status of microbes associated with closed habitation and crew health maintenance. In addition to providing microbial profiles, the ISS-MO team identifies which microbial taxa pose particular threats to crew health. Furthermore, specific ISS-MO project aims shall enable scientists to resolve applicable NASA-Human Research Program integrated research plan risks.

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Space Applications
Millions of microbes live in and among humans on the ISS, where they can threaten crew members’ health. The Microbial Observatory-1 project uses microbial analysis techniques to establish a census of the microorganisms living on ISS surfaces and in its atmosphere. Culture-based analysis can help determine whether some microbes are more virulent in space, and which genetic changes might be involved in this response. A census database will provide a better understanding of microbe diversity on board the station, as well as genetic strategies for identifying specific subsets. Sampling the US modules three times during one year enables researchers to conduct long-term, multigenerational studies of microbial population dynamics. Results from this investigation can be used to evaluate cleaning strategies, and to mitigate microbe-related risks to crew health and spacecraft system performance.

Earth Applications
The Microbial Observatory-1 project provides a basis for using -omics strategies, including genomics, to screen for and identify specific types of microorganisms. The same techniques can be used to identify microbes in hospitals, pharmaceutical laboratories and other environments on Earth where microbe identification is crucial. Results from this investigation provide new insights into microbes’ metabolic pathways, which could be used to develop new drugs and antibacterial products to fight microbes on Earth.

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Operational Requirements and Protocols

Surface and air sampling must be conducted within 2 weeks (+ 4 days) of the unberth of the Dragon spacecraft that returns the samplings to Earth. The samples are stored at room temperature. In case of a delay of the Dragon spacecraft’s return to Earth, the samples are stored in the Cold Stowage for up to two weeks until the unberth of the spacecraft. In case of longer delay, contact slides and adhesive tapes are kept in Cold Stowage whereas swabs, wipes, air filters, and used gloves are kept at -80°C. One crew member performs the sampling session that lasts for ~0.5 hours. Three sessions are required for the full length of the project. The sampling is performed on 8 specific locations inside the US modules for surfaces, and 6 locations for the air. The specific surface sampling locations are: the zero-G stowage rack (ZSR) surface and dining table inside Unity (Node 1); crew quarters (CQ3) interior port wall inside Harmony (Node 2); overhead hatch area of cupola, rack next to waste and hygiene compartment (WHC), and foot platform of the advance resistive exercise device (ARED) inside Tranquility (Node 3); the ZSR surface inside Leonardo PMM; and the rack front near portable water dispenser (PWD) inside Destiny (Laboratory). The air samples are collected inside the same modules as the surface samples.

Most of the sampling procedures have been performed in the past besides the one using polyester wipes. In summary, 8 wipes, swabs, contact slides (two types) and, adhesive tapes are used for surface sampling. Additionally, 6 locations are used to sample the air of the US module using a gelatin filter. The session can be non-continuous if needed; however, it needs to be performed by the same crew member and on the same day. For air sampling, the crew member uses the air sampling device which is currently on board the ISS. A new air filter is placed in the device. The instrument is used for several air cycles and is tethered so the crew member can perform other related tasks. For surface sampling with the polyester wipe, gloves are required to sample 1 m2 surfaces. One pair of gloves is used for each location. The polyester wipes and the gloves are collected in individual Ziploc bags. Swabs are used to sample 15 cm2 of a non-flat pre-defined surface. Two types of contact slides are used during each session at the 8 different locations to culture bacteria and fungi. These contact slides are collected in a bag with levels of containment. Finally, adhesive tapes are placed on surfaces to collected microorganisms from the ISS environment. Subsequently, the wipes and the other sampling devices are stored in a pre-label Ziploc bag. The sampling kit is stored at ambient temperature until the unberth of the Dragon Spacecraft.

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Decadal Survey Recommendations

Plant and Microbial Biology P1
Plant and Microbial Biology P2

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Results/More Information

The complete elimination of germs within spacecraft and space habitats is not possible since human and even cargo are carriers of microorganisms. Fungal colonization of space vessels is nothing new, as various species have been found inside Skylab, Mir, and the International Space Station (ISS). Fungi have been reported to cause damage to electrical and structural components through the decomposition of wire insulation and window gaskets. As durations of manned space missions increase, it is crucial to understand the long-term consequence of microbial growth and exposure in a enclosed space environment. The on-going ISS Microbial Observatory Experiments examine the traits and diversity of microorganisms to better understand how they adapt to space living and how this may affect their interactions with crew members. Assessment of “test-tube” growth characteristics, metabolism, and susceptibility to chemical agents of two independent Aspergillus fumigatus strains, common opportunistic pathogens, isolated from the ISS revealed no outstanding differences between space and Earth that would suggest special fungus adaptation to life aboard the ISS. However, infection study of these fungi in zebrafish larva with immature immune system revealed that the ISS strains were significantly more lethal than their Earth counterparts. Also, 20 moderate health hazard bacterial strains from ISS were isolated, identified, and whole-genome sequences (WGS) were generated. Genetic comparison enables the determination of the microgravity influence on pathogenicity and virulence in these microorganisms. Overall, the space bacteria show increased resistance to one or multiple forms of antibiotics. Changes in the characteristics and population of microbial species combined with changes in the human immune system increase the risk for illness and disease. These findings affirm the need for additional studies of microbes physical traits and biological adaptation in microgravity and other extreme extraterrestrial conditions.

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Results Publications

    Urbaniak C, Checinska Sielaff A, Frey KG, Allen JE, Singh NK, Jaing C, Wheeler K, Venkateswaran KJ.  Detection of antimicrobial resistance genes associated with the International Space Station environmental surfaces. Scientific Reports. 2018 January 16; 8(1): 814. DOI: 10.1038/s41598-017-18506-4. PMID: 29339831.

    Venkateswaran KJ, Singh NK, Checinska Sielaff A, Pope RK, Bergman NH, Van Tongeren SP, Patel NB, Lawson PA, Satomi M, Williamson CH, Sahl JW, Keim P, Pierson DL, Perry JL.  Non-toxin-producing Bacillus cereus strains belonging to the B. anthracis clade isolated from the International Space Station. mSystems. 2017 May-June; 2(3): 16 pp. DOI: 10.1128/mSystems.00021-17. PMID: 28680972.

    Checinska Sielaff A, Singh NK, Allen JE, Thissen J, Jaing C, Venkateswaran KJ.  Draft genome sequences of biosafety level 2 opportunistic pathogens isolated from the environmental surfaces of the International Space Station. Genome Announcements. 2016 December 29; 4(6): e01263-16. DOI: 10.1128/genomeA.01263-16. PMID: 28034853.

    Knox BP, Blachowicz A, Palmer JM, Romsdahl J, Huttenlocher A, Wang CC, Keller NP, Venkateswaran KJ.  Characterization of Aspergillus fumigatus isolates from air and surfaces of the International Space Station. mSphere. 2016 September-October; 1(5): e00227-16. DOI: 10.1128/mSphere.00227-16. PMID: 27830189.

    Seuylemezian A, Singh NK, Vaishampayan PA, Venkateswaran KJ.  Draft genome sequence of Solibacillus kalamii, isolated from an air filter aboard the International Space Station. Genome Announcements. 2017 August 31; 5(35): 2 pp. DOI: 10.1128/genomeA.00696-17. PMID: 28860236.

    Venkateswaran KJ, Checinska Sielaff A, Ratnayake S, Pope RK, Blank TE, Stepanov VG, Fox GE, Van Tongeren SP, Torres C, Allen JE, Jaing C, Pierson DL, Perry JL, Koren S, Phillippy A, Klubnik J, Treangen TJ, Rosovitz MJ, Bergman NH.  Draft genome sequences from a novel clade of Bacillus cereus sensu lato strains, isolated from the International Space Station. Genome Announcements. 2017 August 10; 5(32): 3. DOI: 10.1128/genomeA.00680-17. PMID: 28798168.

    Singh NK, Wood JM, Karouia F, Venkateswaran KJ.  Succession and persistence of microbial communities and antimicrobial resistance genes associated with International Space Station environmental surfaces. Microbiome. 2018 November 13; 6(1): 204. DOI: 10.1186/s40168-018-0585-2. PMID: 30424821.

    Checinska Sielaff A, Kumar RM, Pal D, Mayilraj S, Venkateswaran KJ.  Solibacillus kalamii sp. nov., isolated from a high-efficiency particulate arrestance filter system used in the International Space Station. International Journal of Systematic and Evolutionary Microbiology. 2017 April; 67(4): 896-901. DOI: 10.1099/ijsem.0.001706. PMID: 28475026.

    Be NA, Avila-Herrera A, Allen JE, Singh NK, Checinska Sielaff A, Jaing C, Venkateswaran KJ.  Whole metagenome profiles of particulates collected from the International Space Station. Microbiome. 2017 July 17; 5(1): 81. DOI: 10.1186/s40168-017-0292-4. PMID: 28716113.

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Ground Based Results Publications

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ISS Patents

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