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Yang J, Fu Y, Liu H. Microbiomes of air dust collected during the ground-based closed bioregenerative life support experiment "Lunar Palace 365". ENVIRONMENTAL MICROBIOME 2022; 17:4. [PMID: 35081988 PMCID: PMC8793263 DOI: 10.1186/s40793-022-00399-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 01/07/2022] [Indexed: 05/07/2023]
Abstract
BACKGROUND Understanding the dynamics of airborne microbial communities and antibiotic resistance genes (ARGs) in space life support systems is important because potential pathogens and antibiotic resistance pose a health risk to crew that can lead to mission failure. There have been few reports on the distribution patterns of microbiomes and ARGs in space life support systems. In particular, there have been no detailed investigations of microbiomes and/or antibiotic resistance based on molecular methods in long-term confined bioregenerative life support systems (BLSSs). Therefore, in the present study, we collected air dust samples from two crew shifts, different areas, and different time points in the "Lunar Palace 365" experiment. We evaluated microbial diversity, species composition, functional potential, and antibiotic resistance by combining cultivation-independent analyses (amplicon, shot-gun sequencing, and qPCR). RESULTS We found that the bacterial community diversity in the Lunar Palace1 (LP1) system was higher than that in a controlled environment but lower than that in an open environment. Personnel exchange led to significant differences in bacterial community diversity, and source tracking analysis revealed that most bacteria in the air derived from the cabin crew and plants, but no differences in microbial function or antibiotic resistance were observed. Thus, human presence had the strongest effect on the succession of microbial diversity in the BLSSs. CONCLUSIONS Our results highlight that microbial diversity in BLSSs is heavily influenced by changes in crew and is unique from other open and controlled environments. Our findings can be used to help develop safe, enclosed BLSS that meet the requirements of human survival and habitation in outer space. In addition, our results can further enhance our understanding of the indoor air microbial community and effectively maintain a safe working and living environment, including plant growth.
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Affiliation(s)
- Jianlou Yang
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, No. 37 Xueyuan Road, Beijing, 100191, China
| | - Yuming Fu
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, No. 37 Xueyuan Road, Beijing, 100191, China.
- State Key Laboratory of Virtual Reality Technology and Systems, School of Computer Science and Engineering, Beihang University, Beijing, 100191, China.
- International Joint Research Center of Aerospace Biotechnology and Medical Engineering, Beihang University, Beijing, 100191, China.
| | - Hong Liu
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, No. 37 Xueyuan Road, Beijing, 100191, China.
- State Key Laboratory of Virtual Reality Technology and Systems, School of Computer Science and Engineering, Beihang University, Beijing, 100191, China.
- International Joint Research Center of Aerospace Biotechnology and Medical Engineering, Beihang University, Beijing, 100191, China.
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Chen R, Fang L, Liu J, Herbig B, Norrefeldt V, Mayer F, Fox R, Wargocki P. Cabin air quality on non-smoking commercial flights: A review of published data on airborne pollutants. INDOOR AIR 2021; 31:926-957. [PMID: 33896039 DOI: 10.1111/ina.12831] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/15/2021] [Indexed: 05/24/2023]
Abstract
We reviewed 47 documents published 1967-2019 that reported measurements of volatile organic compounds (VOCs) on commercial aircraft. We compared the measurements with the air quality standards and guidelines for aircraft cabins and in some cases buildings. Average levels of VOCs for which limits exist were lower than the permissible levels except for benzene with average concentration at 5.9 ± 5.5 μg/m3 . Toluene, benzene, ethylbenzene, formaldehyde, acetaldehyde, limonene, nonanal, hexanal, decanal, octanal, acetic acid, acetone, ethanol, butanal, acrolein, isoprene and menthol were the most frequently measured compounds. The concentrations of semi-volatile organic compounds (SVOCs) and other contaminants did not exceed standards and guidelines in buildings except for the average NO2 concentration at 12 ppb. Although the focus was on VOCs, we also retrieved the data on other parameters characterizing cabin environment. Ozone concentration averaged 38 ppb below the upper limit recommended for aircraft. The outdoor air supply rate ranged from 1.7 to 39.5 L/s per person and averaged 6.0 ± 0.8 L/s/p (median 5.8 L/s/p), higher than the minimum level recommended for commercial aircraft. Carbon dioxide concentration averaged 1315 ± 232 ppm, lower than what is permitted in aircraft and close to what is permitted in buildings. Measured temperatures averaged 23.5 ± 0.8°C and were generally within the ranges recommended for avoiding thermal discomfort. Relative humidity averaged 16% ± 5%, lower than what is recommended in buildings.
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Affiliation(s)
- Ruiqing Chen
- Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Lei Fang
- International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, Lyngby, Denmark
| | - Junjie Liu
- Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Britta Herbig
- LMU University Hospital Munich, Institute and Clinic for Occupational, Social and Environmental Medicine, Munich, Germany
| | - Victor Norrefeldt
- Fraunhofer Institute for Building Physics IBP, Holzkirchen Branch, Valley, Germany
| | - Florian Mayer
- Fraunhofer Institute for Building Physics IBP, Holzkirchen Branch, Valley, Germany
| | - Richard Fox
- Aircraft Environment Solutions Inc., San Tan Valley, Arizona, USA
| | - Pawel Wargocki
- International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, Lyngby, Denmark
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Calderón-Ezquerro MDC, Serrano-Silva N, Brunner-Mendoza C. Aerobiological study of bacterial and fungal community composition in the atmosphere of Mexico City throughout an annual cycle. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 278:116858. [PMID: 33740598 DOI: 10.1016/j.envpol.2021.116858] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 01/26/2021] [Accepted: 02/27/2021] [Indexed: 06/12/2023]
Abstract
The atmosphere as a temporary habitat for airborne microbial communities is a valuable topic to explore, and it is through aerobiological studies that the diversity of biological particles and their release, emission, transport, deposition, and impact are assessed. Specific microorganisms are involved in meteorological processes, and phytosanitary and public health concerns. Airborne microbial composition is related to factors such as geographic region and weather conditions. In this study a metagenomic approach was used to determine the composition of bacterial and fungal communities in the air of two different land-use areas (urban area and semi-rural area), during dry and rainy seasons in Mexico City. Air sampling was carried out with a Hirst-type spore trap, collecting the samples simultaneously in both study areas. Forty-two bioaerosol samples were collected, and the DNA obtained was sequenced using Next-Generation Sequencing. The results indicated that the bacterial communities were represented mainly by the phyla Actinobacteria, Proteobacteria, Firmicutes, Bacteroidetes, Cyanobacteria, and the fungal communities by the phyla Ascomycota followed by Basidiomycota. The evident changes in microbial composition were related more to seasonality than to locality, since both UA and SRA showed a high degree of urbanization, despite some differences in land use. Continuous monitoring of atmospheric bioaerosols is essential to determine the influence of meteorological factors on the composition of the aerial microbiota.
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Affiliation(s)
- María Del Carmen Calderón-Ezquerro
- Departamento de Ciencias Ambientales, Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México (UNAM), Circuito Exterior s/n, Coyoacán, Ciudad Universitaria, 04510, Mexico City, Mexico.
| | - Nancy Serrano-Silva
- Departamento de Ciencias Ambientales, Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México (UNAM), Circuito Exterior s/n, Coyoacán, Ciudad Universitaria, 04510, Mexico City, Mexico
| | - Carolina Brunner-Mendoza
- Departamento de Ciencias Ambientales, Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México (UNAM), Circuito Exterior s/n, Coyoacán, Ciudad Universitaria, 04510, Mexico City, Mexico; Departamento de Microbiología y Parasitología, Facultad de Medicina, UNAM, Circuito Exterior s/n, Coyoacán, Ciudad Universitaria, 04510, Mexico City, Mexico
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Weiss H, Hertzberg VS, Dupont C, Espinoza JL, Levy S, Nelson K, Norris S. The Airplane Cabin Microbiome. MICROBIAL ECOLOGY 2019; 77:87-95. [PMID: 29876609 PMCID: PMC6318343 DOI: 10.1007/s00248-018-1191-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 04/11/2018] [Indexed: 05/07/2023]
Abstract
Serving over three billion passengers annually, air travel serves as a conduit for infectious disease spread, including emerging infections and pandemics. Over two dozen cases of in-flight transmissions have been documented. To understand these risks, a characterization of the airplane cabin microbiome is necessary. Our study team collected 229 environmental samples on ten transcontinental US flights with subsequent 16S rRNA sequencing. We found that bacterial communities were largely derived from human skin and oral commensals, as well as environmental generalist bacteria. We identified clear signatures for air versus touch surface microbiome, but not for individual types of touch surfaces. We also found large flight-to-flight beta diversity variations with no distinguishing signatures of individual flights, rather a high between-flight diversity for all touch surfaces and particularly for air samples. There was no systematic pattern of microbial community change from pre- to post-flight. Our findings are similar to those of other recent studies of the microbiome of built environments. In summary, the airplane cabin microbiome has immense airplane to airplane variability. The vast majority of airplane-associated microbes are human commensals or non-pathogenic, and the results provide a baseline for non-crisis-level airplane microbiome conditions.
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Affiliation(s)
- Howard Weiss
- School of Mathematics, The Georgia Institute of Technology, 686 Cherry St. NW, Atlanta, GA 30313 USA
| | - Vicki Stover Hertzberg
- Nell Hodgson Woodruff School of Nursing, Emory University, 1520 Clifton Rd. NE, Atlanta, GA 30322 USA
| | - Chris Dupont
- J. Craig Venter Institute, 4120 Capricorn Lane, La Jolla, CA 92037 USA
| | - Josh L. Espinoza
- J. Craig Venter Institute, 4120 Capricorn Lane, La Jolla, CA 92037 USA
| | - Shawn Levy
- HudsonAlpha Institute for Biotechnology, 601 Genome Way, Huntsville, AL 35806 USA
| | - Karen Nelson
- J. Craig Venter Institute, 9714 Medical Center Drive, Rockville, MD 20850 USA
| | - Sharon Norris
- Boeing Health Services, The Boeing Company, 3156 160th Ave. NE, Bellevue, WA 98008-2245 USA
| | - The FlyHealthy Research Team
- School of Mathematics, The Georgia Institute of Technology, 686 Cherry St. NW, Atlanta, GA 30313 USA
- Nell Hodgson Woodruff School of Nursing, Emory University, 1520 Clifton Rd. NE, Atlanta, GA 30322 USA
- J. Craig Venter Institute, 4120 Capricorn Lane, La Jolla, CA 92037 USA
- HudsonAlpha Institute for Biotechnology, 601 Genome Way, Huntsville, AL 35806 USA
- J. Craig Venter Institute, 9714 Medical Center Drive, Rockville, MD 20850 USA
- Boeing Health Services, The Boeing Company, 3156 160th Ave. NE, Bellevue, WA 98008-2245 USA
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Zhao B, Dewald C, Hennig M, Bossert J, Bauer M, Pletz MW, Jandt KD. Microorganisms @ materials surfaces in aircraft: Potential risks for public health? - A systematic review. Travel Med Infect Dis 2018; 28:6-14. [PMID: 30056140 DOI: 10.1016/j.tmaid.2018.07.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 07/05/2018] [Accepted: 07/25/2018] [Indexed: 02/02/2023]
Abstract
BACKGROUND Civil air travel is increasingly recognized as an important potential source for the rapid spread of infectious diseases that were geographically confined in the past, creating international epidemics with great health and socio-economic impact. OBJECTIVE The objective of this systematic review is to elucidate the correlations of materials surfaces (composition, structure, properties) and microbial dependences on them in aircraft. METHODS The review was prepared according to PRISMA guidelines. Based on a systematic search for studies published before 30 June 2018 in English, we selected and reviewed the contamination, tenacity, and transmission of microorganisms related to specific surfaces within the aircraft cabin. We also reviewed the chemical composition and properties of these surface materials applied within aircraft. RESULTS From a total of 828 records 15 articles were included for further analysis in this systematic review, indicating that the aircraft interior surfaces in seat areas (tray tables, armrests, seat covers) and lavatories (door knob handles, toilet flush buttons) are generally colonized by various types of potentially hazardous microorganisms. CONCLUSIONS The interior surfaces in seat and lavatory areas could pose higher health risks by causing infections due to their relatively high microbial contamination compared with other interior surfaces. The classification, chemical composition, surface structures and physicochemical properties of materials surfaces have a varied effect on the adhesion, colonization, tenacity and potential transmission of microorganisms within the aircraft cabin. Strategies are proposed for the interruption of surface-related infection chains in the aircraft field.
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Affiliation(s)
- Bin Zhao
- Chair of Materials Science (CMS), Otto Schott Institute of Materials Research (OSIM), Friedrich Schiller University Jena, Löbdergraben 32, 07743, Jena, Germany
| | - Carolin Dewald
- Chair of Materials Science (CMS), Otto Schott Institute of Materials Research (OSIM), Friedrich Schiller University Jena, Löbdergraben 32, 07743, Jena, Germany; Jena School for Microbial Communication (JSMC), Friedrich Schiller University Jena, Neugasse 23, 07743, Jena, Germany
| | - Max Hennig
- Chair of Materials Science (CMS), Otto Schott Institute of Materials Research (OSIM), Friedrich Schiller University Jena, Löbdergraben 32, 07743, Jena, Germany
| | - Jörg Bossert
- Chair of Materials Science (CMS), Otto Schott Institute of Materials Research (OSIM), Friedrich Schiller University Jena, Löbdergraben 32, 07743, Jena, Germany
| | - Michael Bauer
- Center for Sepsis Control and Care, Department of Anaesthesiology and Intensive Care Unit, University Hospital Jena, Am Klinikum 1, 07747, Jena, Germany
| | - Mathias W Pletz
- Institute for Infectious Diseases and Infection Control, Center for Sepsis Control and Care, University Hospital Jena, Am Klinikum 1, 07747, Jena, Germany.
| | - Klaus D Jandt
- Chair of Materials Science (CMS), Otto Schott Institute of Materials Research (OSIM), Friedrich Schiller University Jena, Löbdergraben 32, 07743, Jena, Germany; Jena School for Microbial Communication (JSMC), Friedrich Schiller University Jena, Neugasse 23, 07743, Jena, Germany.
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Korves TM, Piceno YM, Tom LM, DeSantis TZ, Jones BW, Andersen GL, Hwang GM. Bacterial communities in commercial aircraft high-efficiency particulate air (HEPA) filters assessed by PhyloChip analysis. INDOOR AIR 2013; 23:50-61. [PMID: 22563927 PMCID: PMC7201892 DOI: 10.1111/j.1600-0668.2012.00787.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Accepted: 04/29/2012] [Indexed: 05/20/2023]
Abstract
UNLABELLED Air travel can rapidly transport infectious diseases globally. To facilitate the design of biosensors for infectious organisms in commercial aircraft, we characterized bacterial diversity in aircraft air. Samples from 61 aircraft high-efficiency particulate air (HEPA) filters were analyzed with a custom microarray of 16S rRNA gene sequences (PhyloChip), representing bacterial lineages. A total of 606 subfamilies from 41 phyla were detected. The most abundant bacterial subfamilies included bacteria associated with humans, especially skin, gastrointestinal and respiratory tracts, and with water and soil habitats. Operational taxonomic units that contain important human pathogens as well as their close, more benign relatives were detected. When compared to 43 samples of urban outdoor air, aircraft samples differed in composition, with higher relative abundance of Firmicutes and Gammaproteobacteria lineages in aircraft samples, and higher relative abundance of Actinobacteria and Betaproteobacteria lineages in outdoor air samples. In addition, aircraft and outdoor air samples differed in the incidence of taxa containing human pathogens. Overall, these results demonstrate that HEPA filter samples can be used to deeply characterize bacterial diversity in aircraft air and suggest that the presence of close relatives of certain pathogens must be taken into account in probe design for aircraft biosensors. PRACTICAL IMPLICATIONS A biosensor that could be deployed in commercial aircraft would be required to function at an extremely low false alarm rate, making an understanding of microbial background important. This study reveals a diverse bacterial background present on aircraft, including bacteria closely related to pathogens of public health concern. Furthermore, this aircraft background is different from outdoor air, suggesting different probes may be needed to detect airborne contaminants to achieve minimal false alarm rates. This study also indicates that aircraft HEPA filters could be used with other molecular techniques to further characterize background bacteria and in investigations in the wake of a disease outbreak.
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Affiliation(s)
- T. M. Korves
- Cognitive Tools and Data Management Department, The MITRE Corporation, Bedford, MA, USA
| | - Y. M. Piceno
- Ecology Department, Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - L. M. Tom
- Ecology Department, Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - T. Z. DeSantis
- Department of Bioinformatics, Second Genome, San Bruno, CA, USA
| | - B. W. Jones
- Department of Mechanical and Nuclear Engineering, Kansas State University, Manhattan, KS, USA
| | - G. L. Andersen
- Ecology Department, Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - G. M. Hwang
- Office of the Chief Engineer, The MITRE Corporation, Woodlawn, MD, USA
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Hasenberg M, Stegemann-Koniszewski S, Gunzer M. Cellular immune reactions in the lung. Immunol Rev 2012; 251:189-214. [DOI: 10.1111/imr.12020] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Mike Hasenberg
- Institute of Experimental Immunology and Imaging; University of Duisburg/Essen; University Hospital; Essen; Germany
| | | | - Matthias Gunzer
- Institute of Experimental Immunology and Imaging; University of Duisburg/Essen; University Hospital; Essen; Germany
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Ghosh S, Osman S, Vaishampayan P, Venkateswaran K. Recurrent isolation of extremotolerant bacteria from the clean room where Phoenix spacecraft components were assembled. ASTROBIOLOGY 2010; 10:325-35. [PMID: 20446872 DOI: 10.1089/ast.2009.0396] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The microbial burden of the Phoenix spacecraft assembly environment was assessed in a systematic manner via several cultivation-based techniques and a suite of NASA-certified, cultivation-independent biomolecule-based detection assays. Extremotolerant bacteria that could potentially survive conditions experienced en route to Mars or on the planet's surface were isolated with a series of cultivation-based assays that promoted the growth of a variety of organisms, including spore formers, mesophilic heterotrophs, anaerobes, thermophiles, psychrophiles, alkaliphiles, and bacteria resistant to UVC radiation and hydrogen peroxide exposure. Samples were collected from the clean room where Phoenix was housed at three different time points, before (1P), during (2P), and after (3P) Phoenix's presence at the facility. There was a reduction in microbial burden of most bacterial groups, including spore formers, in samples 2P and 3P. Analysis of 262 isolates from the facility demonstrated that there was also a shift in predominant cultivable bacterial populations accompanied by a reduction in diversity during 2P and 3P. It is suggested that this shift was a result of increased cleaning when Phoenix was present in the assembly facility and that certain species, such as Acinetobacter johnsonii and Brevundimonas diminuta, may be better adapted to environmental conditions found during 2P and 3P. In addition, problematic bacteria resistant to multiple extreme conditions, such as Bacillus pumilus, were able to survive these periods of increased cleaning.
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Affiliation(s)
- Sudeshna Ghosh
- Biotechnology and Planetary Protection Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
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LA DUC MYRONT, OSMAN SHARIFF, VENKATESWARAN KASTHURI. COMPARATIVE ANALYSIS OF METHODS FOR THE PURIFICATION OF DNA FROM LOW-BIOMASS SAMPLES BASED ON TOTAL YIELD AND CONSERVED MICROBIAL DIVERSITY. ACTA ACUST UNITED AC 2009. [DOI: 10.1111/j.1745-4581.2009.00153.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Osman S, La Duc MT, Dekas A, Newcombe D, Venkateswaran K. Microbial burden and diversity of commercial airline cabin air during short and long durations of travel. ISME JOURNAL 2008; 2:482-97. [PMID: 18256704 PMCID: PMC7099242 DOI: 10.1038/ismej.2008.11] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Total microbial burden and diversity associated with commercial airliner cabin air was assessed by molecular methods in 125 air samples from the business-class sections of 16 domestic and international flights. Viable microbial burden within these cabin air parcels constituted only 1–10% of the total microbial population and ranged from below detection limits to 1.2 × 104 cells m–3 as determined with a validated ATP-based technology. Cultivable bacterial diversity was almost entirely limited to Gram-positive bacteria such as Staphylococcus and Bacillus. In contrast, cloning and sequencing 16S rRNA gene directly from the samples without cultivation indicated a significantly broader diversity, as sequences representing more than 100 species, and encompassing 12 classes of bacteria, were retrieved in varying abundance. Sequences of proteobacterial and Gram-positive lineage were retrieved most frequently (58% and 31% of all clone sequences, respectively), with Gram-positive and α-proteobacterial sequences dominating international flight samples and β- and γ-proteobacterial sequences comprising the largest portion of those retrieved from domestic flights. Significant differences in bacterial load and diversity were noted between samples obtained on domestic and international flights. The disparities observed in microbial abundance and diversity further underscore the immense value of state-of-the art molecular assays in augmenting traditional culture-based techniques.
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Affiliation(s)
- Shariff Osman
- California Institute of Technology, Pasadena, CA, USA
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