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Hauserman MR, Sullivan LE, James KL, Ferraro MJ, Rice KC. Response of Staphylococcus aureus physiology and Agr quorum sensing to low-shear modeled microgravity. J Bacteriol 2024:e0027224. [PMID: 39120147 DOI: 10.1128/jb.00272-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2024] [Accepted: 07/11/2024] [Indexed: 08/10/2024] Open
Abstract
Staphylococcus aureus is commonly isolated from astronauts returning from spaceflight. Previous analysis of omics data from S. aureus low Earth orbit cultures indicated significantly increased expression of the Agr quorum sensing system and its downstream targets in spaceflight samples compared to ground controls. In this current study, the rotary cell culture system (RCCS) was used to investigate the effect of low-shear modeled microgravity (LSMMG) on S. aureus physiology and Agr activity. When cultured in the same growth medium and temperature as the previous spaceflight experiment, S. aureus LSMMG cultures exhibited decreased agr expression and altered growth compared to normal gravity control cultures, which are typically oriented with oxygenation membrane on the bottom of the high aspect rotating vessel (HARV). When S. aureus was grown in an inverted gravity control orientation (oxygenation membrane on top of the HARV), reduced Agr activity was observed relative to both traditional control and LSMMG cultures, signifying that oxygen availability may affect the observed differences in Agr activity. Metabolite assays revealed increased lactate and decreased acetate excretion in both LSMMG and inverted control cultures. Secretomics analysis of LSMMG, control, and inverted control HARV culture supernatants corroborated these results, with inverted and LSMMG cultures exhibiting a decreased abundance of Agr-regulated virulence factors and an increased abundance of proteins expressed in low-oxygen conditions. Collectively, these studies suggest that the orientation of the HARV oxygenation membrane can affect S. aureus physiology and Agr quorum sensing in the RCCS, a variable that should be considered when interpreting data using this ground-based microgravity model.IMPORTANCES. aureus is commonly isolated from astronauts returning from spaceflight and from surfaces within human-inhabited closed environments such as spacecraft. Astronaut health and immune function are significantly altered in spaceflight. Therefore, elucidating the effects of microgravity on S. aureus physiology is critical for assessing its pathogenic potential during long-term human space habitation. These results also highlight the necessity of eliminating potential confounding factors when comparing simulated microgravity model data with actual spaceflight experiments.
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Affiliation(s)
- Matthew R Hauserman
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, Florida, USA
| | - Leia E Sullivan
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, Florida, USA
| | - Kimberly L James
- Department of Biological Sciences, Florida Gulf Coast University, Fort Myers, Florida, USA
| | - Mariola J Ferraro
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, Florida, USA
| | - Kelly C Rice
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, Florida, USA
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2
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Hauserman MR, Ferraro MJ, Carroll RK, Rice KC. Altered quorum sensing and physiology of Staphylococcus aureus during spaceflight detected by multi-omics data analysis. NPJ Microgravity 2024; 10:2. [PMID: 38191486 PMCID: PMC10774393 DOI: 10.1038/s41526-023-00343-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 12/15/2023] [Indexed: 01/10/2024] Open
Abstract
Staphylococcus aureus colonizes the nares of approximately 30% of humans, a risk factor for opportunistic infections. To gain insight into S. aureus virulence potential in the spaceflight environment, we analyzed RNA-Seq, cellular proteomics, and metabolomics data from the "Biological Research in Canisters-23" (BRIC-23) GeneLab spaceflight experiment, a mission designed to measure the response of S. aureus to growth in low earth orbit on the international space station. This experiment used Biological Research in Canisters-Petri Dish Fixation Units (BRIC-PDFUs) to grow asynchronous ground control and spaceflight cultures of S. aureus for 48 h. RNAIII, the effector of the Accessory Gene Regulator (Agr) quorum sensing system, was the most highly upregulated gene transcript in spaceflight relative to ground controls. The agr operon gene transcripts were also highly upregulated during spaceflight, followed by genes encoding phenol-soluble modulins and secreted proteases, which are positively regulated by Agr. Upregulated spaceflight genes/proteins also had functions related to urease activity, type VII-like Ess secretion, and copper transport. We also performed secretome analysis of BRIC-23 culture supernatants, which revealed that spaceflight samples had increased abundance of secreted virulence factors, including Agr-regulated proteases (SspA, SspB), staphylococcal nuclease (Nuc), and EsxA (secreted by the Ess system). These data also indicated that S. aureus metabolism is altered in spaceflight conditions relative to the ground controls. Collectively, these data suggest that S. aureus experiences increased quorum sensing and altered expression of virulence factors in response to the spaceflight environment that may impact its pathogenic potential.
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Affiliation(s)
- Matthew R Hauserman
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, FL, USA
| | - Mariola J Ferraro
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, FL, USA
| | - Ronan K Carroll
- Department of Biological Sciences, Ohio University, Athens, OH, USA
| | - Kelly C Rice
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, FL, USA.
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3
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Gricajeva A, Buchovec I, Kalėdienė L, Badokas K, Vitta P. Riboflavin- and chlorophyllin-based antimicrobial photoinactivation of Brevundimonas sp. ESA1 biofilms. Front Cell Infect Microbiol 2022; 12:1006723. [PMID: 36262183 PMCID: PMC9575555 DOI: 10.3389/fcimb.2022.1006723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 09/01/2022] [Indexed: 11/13/2022] Open
Abstract
Some Brevundimonas spp. are globally emerging opportunistic pathogens that can be dangerous to individuals with underlying medical conditions and for those who are immunocompromised. Gram-negative Brevundimonas spp. can form resilient sessile biofilms and are found not only in different confined terrestrial settings (e.g., hospitals) but are also frequently detected in spacecraft which is inhabited by astronauts that can have altered immunity. Therefore, Brevundimonas spp. pose a serious health hazard in different environments, especially in its biofilm form. Conventional antimicrobials applied to disrupt, inactivate, or prevent biofilm formation have limited efficiency and applicability in different closed-loop systems. Therefore, new, effective, and safe biofilm control technologies are in high demand. The present work aimed to investigate antimicrobial photoinactivation (API) of Brevundimonas sp. ESA1 monocultural biofilms mediated by non-toxic, natural photosensitizers such as riboflavin (RF) and chlorophyllin (Chl) with an emphasis of this technology as an example to be safely used in closed-loop systems such as spacecraft. The present study showed that Chl-based API had a bactericidal effect on Brevundimonas sp. ESA1 biofilms at twice the lower irradiation doses than was needed when applying RF-based API. Long-term API based on RF and Chl using 450 nm low irradiance plate has also been studied in this work as a more practically applicable API method. The ability of Brevundimonas sp. ESA1 biofilms to reduce alamarBlue™ and regrowth analysis have revealed that after the applied photoinactivation, bacteria can enter a viable but non-culturable state with no ability to resuscitate in some cases.
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Affiliation(s)
- Alisa Gricajeva
- Department of Microbiology and Biotechnology, Life Sciences Center, Institute of Biosciences, Vilnius University, Vilnius, Lithuania
- *Correspondence: Alisa Gricajeva,
| | - Irina Buchovec
- Institute of Photonics and Nanotechnology, Faculty of Physics, Vilnius University, Vilnius, Lithuania
| | - Lilija Kalėdienė
- Department of Microbiology and Biotechnology, Life Sciences Center, Institute of Biosciences, Vilnius University, Vilnius, Lithuania
| | - Kazimieras Badokas
- Institute of Photonics and Nanotechnology, Faculty of Physics, Vilnius University, Vilnius, Lithuania
| | - Pranciškus Vitta
- Institute of Photonics and Nanotechnology, Faculty of Physics, Vilnius University, Vilnius, Lithuania
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4
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Kumar R, Sood U, Kaur J, Anand S, Gupta V, Patil KS, Lal R. The rising dominance of microbiology: what to expect in the next 15 years? Microb Biotechnol 2022; 15:110-128. [PMID: 34713975 PMCID: PMC8719816 DOI: 10.1111/1751-7915.13953] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 10/06/2021] [Indexed: 01/10/2023] Open
Abstract
What microbiology beholds after a decade and a half in the future requires a vision based on the facts and ongoing trends in research and technological advancements. While the latter, assisted by microbial dark matter, presents a greater potential of creating an upsurge in in-situ and ex-situ rapid microbial detection techniques, this anticipated change will also set forth a revolution in microbial cultivation and diversity analyses. The availability of a microbial genetic toolbox at the expanse will help complement the current understanding of the microbiome and assist in real-time monitoring of the dynamics for detecting the health status of the host with utmost precision. Alongside, in light of the emerging infectious diseases, antimicrobial resistance (AMR) and social demands for safer and better health care alternatives, microbiology laboratories are prospected to drift in terms of the volume and nature of research and outcomes. With today's microbiological lens, one can predict with certainty that in the years to come, microbes will play a significant role in therapeutic treatment and the designing of novel diagnostic techniques. Another area where the scope of microbial application seems to be promising is the use of novel probiotics as a method to offer health benefits whilst promoting metabolic outputs specific for microbiome replenishment. Nonetheless, the evolution of extraterrestrial microbes or the adaptation of earth microbes as extraterrestrial residents are also yet another prominent microbial event one may witness in the upcoming years. But like the two sides of the coin, there is also an urgent need to dampen the bloom of urbanization, overpopulation and global trade and adopting sustainable approaches to control the recurrence of epidemics and pandemics.
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Affiliation(s)
- Roshan Kumar
- Post‐Graduate Department of ZoologyMagadh UniversityBodh GayaBihar824234India
| | - Utkarsh Sood
- The Energy and Resources InstituteDarbari Seth Block, IHC Complex, Lodhi RoadNew Delhi110003India
| | - Jasvinder Kaur
- Department of ZoologyGargi CollegeUniversity of DelhiSiri Fort RoadNew Delhi110049India
| | - Shailly Anand
- Department of ZoologyDeen Dayal Upadhyaya CollegeUniversity of DelhiDwarkaNew Delhi110078India
| | - Vipin Gupta
- Indira Paryavaran BhawanMinistry of Environment, Forest and Climate ChangeLodi ColonyNew Delhi110003India
| | - Kishor Sureshbhai Patil
- Department of Biological SciencesP. D. Patel Institute of Applied SciencesCharotar University of Science and Technology (CHARUSAT)ChangaGujarat388421India
| | - Rup Lal
- The Energy and Resources InstituteDarbari Seth Block, IHC Complex, Lodhi RoadNew Delhi110003India
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Abstract
Microbial research in space is being conducted for almost 50 years now. The closed system of the International Space Station (ISS) has acted as a microbial observatory for the past 10 years, conducting research on adaptation and survivability of microorganisms exposed to space conditions. This adaptation can be either beneficial or detrimental to crew members and spacecraft. Therefore, it becomes crucial to identify the impact of two primary stress conditions, namely, radiation and microgravity, on microbial life aboard the ISS. Elucidating the mechanistic basis of microbial adaptation to space conditions aids in the development of countermeasures against their potentially detrimental effects and allows us to harness their biotechnologically important properties. Several microbial processes have been studied, either in spaceflight or using devices that can simulate space conditions. However, at present, research is limited to only a few microorganisms, and extensive research on biotechnologically important microorganisms is required to make long-term space missions self-sustainable.
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Affiliation(s)
- Swati Bijlani
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, 1985 Zonal Avenue, Los Angeles, CA 90089, USA
| | - Elisa Stephens
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, 1985 Zonal Avenue, Los Angeles, CA 90089, USA
| | - Nitin Kumar Singh
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | | | - Clay C C Wang
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, 1985 Zonal Avenue, Los Angeles, CA 90089, USA
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LaPelusa M, Donoviel D, Branzini SE, Carlson PE, Culler S, Cheema AK, Kaddurah-Daouk R, Kelly D, de Cremoux I, Knight R, Krajmalnik-Brown R, Mayo SL, Mazmanian SK, Mayer EA, Petrosino JF, Garrison K. Microbiome for Mars: surveying microbiome connections to healthcare with implications for long-duration human spaceflight, virtual workshop, July 13, 2020. MICROBIOME 2021; 9:2. [PMID: 33397500 PMCID: PMC7781430 DOI: 10.1186/s40168-020-00951-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 12/06/2020] [Indexed: 06/12/2023]
Abstract
The inaugural "Microbiome for Mars" virtual workshop took place on July 13, 2020. This event assembled leaders in microbiome research and development to discuss their work and how it may relate to long-duration human space travel. The conference focused on surveying current microbiome research, future endeavors, and how this growing field could broadly impact human health and space exploration. This report summarizes each speaker's presentation in the order presented at the workshop.
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Affiliation(s)
- Michael LaPelusa
- Department of Medicine, Vanderbilt University Medical Center, One Hundred Oaks - North 719 Thompson Lane Suite 20400, Nashville, TN, 37204, USA.
| | - Dorit Donoviel
- Department of Pharmacology and Chemical Biology, Center for Space Medicine, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Sergio E Branzini
- Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, CA, 94158, USA
| | - Paul E Carlson
- Laboratory of Mucosal Pathogens and Cellular Immunology, Division of Bacterial, Parasitic, and Allergenic Products, Office of Vaccines Research and Review, Center for Biologics Evaluation and Research, United States Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Stephanie Culler
- Persephone Biosciences Inc, JLABS, 3210 Merryfield Row, San Diego, CA, 92121, USA
| | - Amrita K Cheema
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, 20007, USA
| | - Rima Kaddurah-Daouk
- Department of Psychiatry and Behavioral Sciences, Department of Medicine and the Duke Institute for Brain Sciences, Duke University, Durham, NC, 27708, USA
| | - Denise Kelly
- Seventure Partners, 5-7 rue de Monttessuy, 75340 Cedex 07, Paris, France
| | | | - Rob Knight
- Departments of Pediatrics, Bioengineering, and Computer Science & Engineering, University of California San Diego, 9500 Gilman Drive, MC 0763, La Jolla, CA, 92093-0763, USA
| | - Rosa Krajmalnik-Brown
- Biodesign Center for Health Through Microbiomes, Arizona State University, Tempe, AZ, USA
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ, USA
| | - Stephen L Mayo
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 E. California Bl, Pasadena, CA, 91125, USA
| | - Sarkis K Mazmanian
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 E. California Bl, Pasadena, CA, 91125, USA
| | - Emeran A Mayer
- G. Oppenheimer Family Center for Neurobiology of Stress and Resilience, Ingestive Behavior and Obesity Program, University of California Los Angeles, Los Angeles, CA, USA
- Vatche and Tamar Manoukian Division of Digestive Diseases, University of California Los Angeles, Los Angeles, CA, USA
- David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Joseph F Petrosino
- Department of Molecular Virology and Microbiology, Alkek Center for Metagenomics and Microbiome Research, Baylor College of Medicine, Houston, Texas, USA
| | - Keith Garrison
- Department of Medicine, The University of Texas at Houston Health Sciences Center, 6431 Fannin St, Houston, TX, 77030, USA.
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7
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Brzezicki MA, Crockett DC, Cooney A, Strachan JM. Letter Regarding "How to Manage Head Injury With COVID-19 Pneumonitis On Mars? Rare But High Impact Complex Medical Emergencies In Space". J Surg Res 2020; 258:457-459. [PMID: 33039108 PMCID: PMC7494297 DOI: 10.1016/j.jss.2020.07.085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Accepted: 07/13/2020] [Indexed: 11/25/2022]
Affiliation(s)
- Maksymilian A Brzezicki
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK; Intensive Care Unit, Milton Keynes University Hospital, Milton Keynes, UK.
| | - Douglas C Crockett
- Intensive Care Unit, Milton Keynes University Hospital, Milton Keynes, UK; Exeter College, University of Oxford, Oxford. UK
| | - Andrew Cooney
- Intensive Care Unit, Milton Keynes University Hospital, Milton Keynes, UK
| | - Jamie M Strachan
- Intensive Care Unit, Milton Keynes University Hospital, Milton Keynes, UK
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8
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Antimicrobial Photoinactivation Approach Based on Natural Agents for Control of Bacteria Biofilms in Spacecraft. Int J Mol Sci 2020; 21:ijms21186932. [PMID: 32967302 PMCID: PMC7554952 DOI: 10.3390/ijms21186932] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 01/08/2023] Open
Abstract
A spacecraft is a confined system that is inhabited by a changing microbial consortium, mostly originating from life-supporting devices, equipment collected in pre-flight conditions, and crewmembers. Continuous monitoring of the spacecraft’s bioburden employing culture-based and molecular methods has shown the prevalence of various taxa, with human skin-associated microorganisms making a substantial contribution to the spacecraft microbiome. Microorganisms in spacecraft can prosper not only in planktonic growth mode but can also form more resilient biofilms that pose a higher risk to crewmembers’ health and the material integrity of the spacecraft’s equipment. Moreover, bacterial biofilms in space conditions are characterized by faster formation and acquisition of resistance to chemical and physical effects than under the same conditions on Earth, making most decontamination methods unsafe. There is currently no reported method available to combat biofilm formation in space effectively and safely. However, antibacterial photodynamic inactivation based on natural photosensitizers, which is reviewed in this work, seems to be a promising method.
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Senatore G, Mastroleo F, Leys N, Mauriello G. Growth of Lactobacillus reuteri DSM17938 Under Two Simulated Microgravity Systems: Changes in Reuterin Production, Gastrointestinal Passage Resistance, and Stress Genes Expression Response. ASTROBIOLOGY 2020; 20:1-14. [PMID: 31977256 DOI: 10.1089/ast.2019.2082] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Extreme factors such as space microgravity, radiation, and magnetic field differ from those that occur on Earth. Microgravity may induce and select some microorganisms for physiological, metabolic, and/or genetic variations. This study was conducted to determine the effects of simulated microgravity conditions on the metabolism and gene expression of the probiotic bacterium Lactobacillus reuteri DSM17938. To investigate microbial response to simulated microgravity, two devices-the rotating wall vessel (RWV) and the random positioning machine (RPM)-were used. Microbial growth, reuterin production, and resistance to gastrointestinal passage were assessed, and morphological characteristics were analyzed by scanning electron microscopy. The expression of some selected genes that are responsive to stress conditions and to bile salts stress was evaluated through real-time quantitative polymerase chain reaction assay. Monitoring of bacterial growth, cell size, and shape under simulated microgravity did not reveal differences compared with 1 × g controls. On the contrary, an enhanced production of reuterin and a greater tolerance to the gastrointestinal passage were observed. Moreover, some stress genes were upregulated under RWV conditions, especially after 24 h of treatment, whereas RPM conditions seemed to determine a downregulation over time of the same stress genes. These results show that simulated microgravity could alter some physiological characteristics of L. reuteri DSM17938 with regard to tolerance toward stress conditions encountered on space missions and could be useful to elucidate the adaptation mechanisms of microbes to the space environment.
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Affiliation(s)
- Giuliana Senatore
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
| | - Felice Mastroleo
- Microbiology Unit, Belgian Nuclear Research Centre (SCK●CEN), Mol, Belgium
| | - Natalie Leys
- Microbiology Unit, Belgian Nuclear Research Centre (SCK●CEN), Mol, Belgium
| | - Gianluigi Mauriello
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
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Vaishampayan A, Grohmann E. Multi-resistant biofilm-forming pathogens on the International Space Station. J Biosci 2019; 44:125. [PMID: 31719234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The International Space Station (ISS) is a confined and closed habitat with unique conditions such as cosmic radiation, and microgravity. These conditions have a strong effect on the human and spacecraft microflora. They can affect the immune response of the crew-members, thus posing a threat to their health. Microbial diversity and abundance of microorganisms from surfaces, air filters and air samples on the ISS have been studied. Enterobacteriaceae, Bacillus spp., Propionibacterium spp., Corynebacterium spp., and Staphylococcus spp. were among the most frequently isolated bacteria. Microbial growth, biofilm formation, stress response, and pathogenicity are affected by microgravity. Increased resistance to antibiotics in bacteria isolated from the ISS has often been reported. Enterococcus faecalis and Staphylococcus spp. isolates from the ISS have been shown to harbor plasmid-encoded transfer genes. These genes facilitate the dissemination of antibiotic resistances. These features of ISS-pathogens call for novel approaches including highly effective antimicrobials which can be easily used on the ISS. A promising material is the antimicrobial surface coating AGXX, a self-recycling material consisting of two noble metals. It drastically reduced microbial growth of multi-resistant human pathogens, such as staphylococci and enterococci. Further novel approaches include the application of cold atmospheric plasma for the sterilization of spacecrafts.
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Affiliation(s)
- Ankita Vaishampayan
- Life Sciences and Technology, Beuth University of Applied Sciences, Berlin, Germany
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11
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Vaishampayan A, Grohmann E. Multi-resistant biofilm-forming pathogens on the International Space Station. J Biosci 2019. [DOI: 10.1007/s12038-019-9929-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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12
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Voorhies AA, Mark Ott C, Mehta S, Pierson DL, Crucian BE, Feiveson A, Oubre CM, Torralba M, Moncera K, Zhang Y, Zurek E, Lorenzi HA. Study of the impact of long-duration space missions at the International Space Station on the astronaut microbiome. Sci Rep 2019; 9:9911. [PMID: 31289321 PMCID: PMC6616552 DOI: 10.1038/s41598-019-46303-8] [Citation(s) in RCA: 113] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 06/17/2019] [Indexed: 12/16/2022] Open
Abstract
Over the course of a mission to the International Space Station (ISS) crew members are exposed to a number of stressors that can potentially alter the composition of their microbiomes and may have a negative impact on astronauts’ health. Here we investigated the impact of long-term space exploration on the microbiome of nine astronauts that spent six to twelve months in the ISS. We present evidence showing that the microbial communities of the gastrointestinal tract, skin, nose and tongue change during the space mission. The composition of the intestinal microbiota became more similar across astronauts in space, mostly due to a drop in the abundance of a few bacterial taxa, some of which were also correlated with changes in the cytokine profile of crewmembers. Alterations in the skin microbiome that might contribute to the high frequency of skin rashes/hypersensitivity episodes experienced by astronauts in space were also observed. The results from this study demonstrate that the composition of the astronauts’ microbiome is altered during space travel. The impact of those changes on crew health warrants further investigation before humans embark on long-duration voyages into outer space.
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Affiliation(s)
- Alexander A Voorhies
- Department of Infectious Diseases, J. Craig Venter Institute, Rockville, MD, USA
| | - C Mark Ott
- NASA-Johnson Space Center, Houston, TX, USA
| | | | | | | | | | | | - Manolito Torralba
- Department of Infectious Diseases, J. Craig Venter Institute, Rockville, MD, USA
| | - Kelvin Moncera
- Department of Infectious Diseases, J. Craig Venter Institute, Rockville, MD, USA
| | - Yun Zhang
- Department of Infectious Diseases, J. Craig Venter Institute, Rockville, MD, USA
| | | | - Hernan A Lorenzi
- Department of Infectious Diseases, J. Craig Venter Institute, Rockville, MD, USA.
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Kim HW, Rhee MS. Novel Antibiotic Testing Approaches Reveal Reduced Antibiotic Efficacy Against Shiga Toxin-Producing Escherichia coli O157:H7 Under Simulated Microgravity. Front Microbiol 2019; 9:3214. [PMID: 30619237 PMCID: PMC6308135 DOI: 10.3389/fmicb.2018.03214] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 12/11/2018] [Indexed: 11/13/2022] Open
Abstract
As a foodborne and environmental pathogen, Shiga toxin-producing Escherichia coli O157:H7 could pose a health threat to immunocompromised astronauts during a space mission. In this study, novel approaches, including real-time testing and direct evaluation of resistance mechanisms, were used to evaluate antibiotic efficacy against E. coli O157:H7 under low-shear modeled microgravity (LSMMG) produced using a rotary cell culture system. When compared with normal gravity (NG), bacterial growth was increased under LSMMG in the presence of sub-inhibitory nalidixic acid concentrations and there was an accompanying up-regulation of stress-related genes. LSMMG also induced transcriptional changes of the virulence genes stx1 and stx2, highlighting the potential risk of inappropriate antibiotic use during a spaceflight. The degree of bacterial cell damage induced by the antibiotics was reduced under LSMMG, suggesting low induction of reactive oxygen species. Efflux pumps were also shown to play an important role in these responses. Increased cell filamentation was observed under LSMMG upon ampicillin treatment, possibly reflecting a protective mechanism against exposure to antibiotics. These observations indicate that, in the presence of antibiotics, the survival of E. coli O157:H7 is greater under LSMMG than under NG, indicating that antibiotic therapies may need to be adjusted during space missions.
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Affiliation(s)
- Hye Won Kim
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, South Korea
| | - Min Suk Rhee
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, South Korea
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14
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Impact of the Mk VI SkinSuit on skin microbiota of terrestrial volunteers and an International Space Station-bound astronaut. NPJ Microgravity 2017; 3:23. [PMID: 28894789 PMCID: PMC5589758 DOI: 10.1038/s41526-017-0029-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 08/15/2017] [Accepted: 08/15/2017] [Indexed: 12/11/2022] Open
Abstract
Microgravity induces physiological deconditioning due to the absence of gravity loading, resulting in bone mineral density loss, atrophy of lower limb skeletal and postural muscles, and lengthening of the spine. SkinSuit is a lightweight compression suit designed to provide head-to-foot (axial) loading to counteract spinal elongation during spaceflight. As synthetic garments may impact negatively on the skin microbiome, we used 16S ribosomal RNA (rRNA) gene amplicon procedures to define bacterial skin communities at sebaceous and moist body sites of five healthy male volunteers undergoing SkinSuit evaluation. Each volunteer displayed a diverse, distinct bacterial population at each skin site. Short (8 h) periods of dry hyper-buoyancy flotation wearing either gym kit or SkinSuit elicited changes in the composition of the skin microbiota at the genus level but had little or no impact on community structure at the phylum level or the richness and diversity of the bacterial population. We also determined the composition of the skin microbiota of an astronaut during pre-flight training, during an 8-day visit to the International Space Station involving two 6–7 h periods of SkinSuit wear, and for 1 month after return. Changes in composition of bacterial skin communities at five body sites were strongly linked to changes in geographical location. A distinct ISS bacterial microbiota signature was found which reversed to a pre-flight profile on return. No changes in microbiome complexity or diversity were noted, with little evidence for colonisation by potentially pathogenic bacteria; we conclude that short periods of SkinSuit wear induce changes to the composition of the skin microbiota but these are unlikely to compromise the healthy skin microbiome. A compression garment that applies gravity-like pressure to the skin alters the composition of skin microbes, but not in a dangerous manner. A team led by Peter Taylor from University College London, UK, characterised the bacterial skin communities at dry and moist body sites of five Earth-bound volunteers before and after wearing the Mk VI SkinSuit, which creates a pressure loading system that simulates gravity’s effects. 8 h in the SkinSuit changed the skin microbiota at the genus level but had little to no impact in community structure. The researchers observed more dramatic changes in one astronaut who wore the garment on the International Space Station. However, the microbial makeup reverted back to pre-flight profiles upon the astronaut’s return to Earth. The findings suggest that short-term SkinSuit wear is unlikely to compromise bacterial skin health.
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Shi J, Wang Y, He J, Li P, Jin R, Wang K, Xu X, Hao J, Zhang Y, Liu H, Chen X, Wu H, Ge Q. Intestinal microbiota contributes to colonic epithelial changes in simulated microgravity mouse model. FASEB J 2017; 31:3695-3709. [PMID: 28495755 DOI: 10.1096/fj.201700034r] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 04/24/2017] [Indexed: 12/30/2022]
Abstract
Exposure to microgravity leads to alterations in multiple systems, but microgravity-related changes in the gastrointestinal tract and its clinical significance have not been well studied. We used the hindlimb unloading (HU) mouse model to simulate a microgravity condition and investigated the changes in intestinal microbiota and colonic epithelial cells. Compared with ground-based controls (Ctrls), HU affected fecal microbiota composition with a profile that was characterized by the expansion of Firmicutes and decrease of Bacteroidetes. The colon epithelium of HU mice showed decreased goblet cell numbers, reduced epithelial cell turnover, and decreased expression of genes that are involved in defense and inflammatory responses. As a result, increased susceptibility to dextran sulfate sodium-induced epithelial injury was observed in HU mice. Cohousing of Ctrl mice with HU mice resulted in HU-like epithelial changes in Ctrl mice. Transplantation of feces from Ctrl to HU mice alleviated these epithelial changes in HU mice. Results indicate that HU changes intestinal microbiota, which leads to altered colonic epithelial cell homeostasis, impaired barrier function, and increased susceptibility to colitis. We further demonstrate that alteration in gastrointestinal motility may contribute to HU-associated dysbiosis. These animal results emphasize the necessity of evaluating astronauts' intestinal homeostasis during distant space travel.-Shi, J., Wang, Y., He, J., Li, P., Jin, R., Wang, K., Xu, X., Hao, J., Zhang, Y., Liu, H., Chen, X., Wu, H., Ge, Q. Intestinal microbiota contributes to colonic epithelial changes in simulated microgravity mouse model.
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Affiliation(s)
- Junxiu Shi
- Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, Peking University Health Sciences Center, Beijing, China
| | - Yifan Wang
- Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, Peking University Health Sciences Center, Beijing, China
| | - Jian He
- State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China
| | - Pingping Li
- Shengjing Hospital, China Medical University, Hepin District, Shenyang, China
| | - Rong Jin
- Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, Peking University Health Sciences Center, Beijing, China
| | - Ke Wang
- Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, Peking University Health Sciences Center, Beijing, China
| | - Xi Xu
- Center for Molecular Metabolism, Nanjing University of Science and Technology, Nanjing, China
| | - Jie Hao
- Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, Peking University Health Sciences Center, Beijing, China
| | - Yan Zhang
- Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, Peking University Health Sciences Center, Beijing, China
| | - Hongju Liu
- Shengjing Hospital, China Medical University, Hepin District, Shenyang, China
| | - Xiaoping Chen
- Shengjing Hospital, China Medical University, Hepin District, Shenyang, China
| | - Hounan Wu
- Peking University Medical and Health Analytical Center, Peking University Health Science Center, Beijing, China
| | - Qing Ge
- Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, Peking University Health Sciences Center, Beijing, China;
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Urbaniak C, Reid G. The potential influence of the microbiota and probiotics on women during long spaceflights. ACTA ACUST UNITED AC 2016; 12:193-8. [PMID: 26901697 DOI: 10.2217/whe.15.101] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Humans have been exploring space for almost 55 years but space travel comes with many psychological and physiological changes that astronauts have to adapt to, both during and post flight missions. Now, with the reality of such missions lasting years, maintaining proper health of the flight crew is a high priority. While conditions such as nausea, bone loss, renal calculi and depression have been recognized, and approaches to medical and surgical care in space considered, the influence of the microbiota could be of added significance in maintaining astronaut health. While probiotics have long been part of the Russian cosmonaut diet, their use for specific health concerns of women has not been assessed. In this article, we explore the ways in which the microbiome may influence the health of female astronauts during long space flights, and present a rationale for the use of probiotics.
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Affiliation(s)
- Camilla Urbaniak
- Lawson Health Research Institute, London, ON, N6A 4V2, Canada.,Department of Microbiology & Immunology, Western University, London, ON, N6A 5C1, Canada
| | - Gregor Reid
- Lawson Health Research Institute, London, ON, N6A 4V2, Canada.,Department of Microbiology & Immunology, Western University, London, ON, N6A 5C1, Canada
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18
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Mermel LA. Infection prevention and control during prolonged human space travel. Clin Infect Dis 2012; 56:123-30. [PMID: 23051761 DOI: 10.1093/cid/cis861] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Prolonged human spaceflight to another planet or an asteroid will introduce unique challenges of mitigating the risk of infection. During space travel, exposure to microgravity, radiation, and stress alter human immunoregulatory responses, which can in turn impact an astronaut's ability to prevent acquisition of infectious agents or reactivation of latent infection. In addition, microgravity affects virulence, growth kinetics, and biofilm formation of potential microbial pathogens. These interactions occur in a confined space in microgravity, providing ample opportunity for heavy microbial contamination of the environment. In addition, there is the persistence of aerosolized, microbe-containing particles. Any mission involving prolonged human spaceflight must be carefully planned to minimize vulnerabilities and maximize the likelihood of success.
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Affiliation(s)
- Leonard A Mermel
- Department of Medicine, Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA
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19
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Saei AA, Barzegari A. The microbiome: the forgotten organ of the astronaut’s body – probiotics beyond terrestrial limits. Future Microbiol 2012; 7:1037-46. [DOI: 10.2217/fmb.12.82] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Space medicine research has drawn immense attention toward provision of efficient life support systems during long-term missions into space. However, in extended missions, a wide range of diseases may affect astronauts. In space medicine research, the gastrointestinal microbiome and its role in maintaining astronauts’ health has received little attention. We would like to draw researchers’ attention to the significant role of microbiota. Because of the high number of microorganisms in the human body, man has been called a ‘supra-organism’ and gastrointestinal flora has been referred to as ‘a virtual organ of the human body’. In space, the lifestyle, sterility of spaceship and environmental stresses can result in alterations in intestinal microbiota, which can lead to an impaired immunity and predispose astronauts to illness. This concern is heightened by increase in virulence of pathogens in microgravity. Thus, design of a personal probiotic kit is recommended to improve the health status of astronauts.
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Affiliation(s)
- Amir Ata Saei
- Research Center for Pharmaceutical Nanotechnology, Astrobiology & Space Medicine Laboratory, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Abolfazl Barzegari
- Research Center for Pharmaceutical Nanotechnology, Astrobiology & Space Medicine Laboratory, Tabriz University of Medical Sciences, Tabriz, Iran
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Guéguinou N, Huin-Schohn C, Bascove M, Bueb JL, Tschirhart E, Legrand-Frossi C, Frippiat JP. Could spaceflight-associated immune system weakening preclude the expansion of human presence beyond Earth's orbit? J Leukoc Biol 2009; 86:1027-38. [DOI: 10.1189/jlb.0309167] [Citation(s) in RCA: 216] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Taylor PW, Sommer AP. Towards rational treatment of bacterial infections during extended space travel. Int J Antimicrob Agents 2005; 26:183-7. [PMID: 16118047 PMCID: PMC2025679 DOI: 10.1016/j.ijantimicag.2005.06.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In the next 15-30 years, manned space flight to Mars, our planetary neighbour, will become a reality and astronauts are likely to spend at least 2-3 years away from Earth. Time spent in such extreme environments will result in a diminution of immune status and profound changes in the human bacterial microflora. In microgravity, the efficacy of antibiotics is reduced and microbial mutation rates increase dramatically. These factors will impinge on the capacity to treat effectively the infections that will doubtless arise during such long and stressful endeavour. We highlight new rationales for the treatment of infectious disease that may be applicable to therapy in extreme environments such as deep space.
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Affiliation(s)
- Peter W Taylor
- Microbiology Group, Department of Pharmaceutics, School of Pharmacy, University of London, 29-39 Brunswick Square, London WC1N 1AX, UK.
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Li Y, Kawamura Y, Fujiwara N, Naka T, Liu H, Huang X, Kobayashi K, Ezaki T. Rothia aeria sp. nov., Rhodococcus baikonurensis sp. nov. and Arthrobacter russicus sp. nov., isolated from air in the Russian space laboratory Mir. Int J Syst Evol Microbiol 2004; 54:827-835. [PMID: 15143031 DOI: 10.1099/ijs.0.02828-0] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Four Gram-positive bacteria, strains A1-17BT, A1-22T, A1-3T and A1-8, isolated from the air in the Russian space laboratory Mir, were subjected to a polyphasic taxonomic study. Phylogenetic analysis of the bacteria based on their 16S rDNA sequence showed that they belong to the genera Rothia (A1-17BT), Rhodococcus (A1-22T) and Arthrobacter (A1-3T and A1-8). Morphological, physiological, chemotaxonomic and genomic characteristics supported the assignments of these strains to these genera, but they could not be classified as any existing species within each respective genus. 16S rDNA similarity values between strain A1-17BT and its neighbours, Rothia dentocariosa genomovar II, Rothia dentocariosa, Rothia mucilaginosa and Rothia nasimurium, were respectively 99·8, 98·0, 96·4 and 95·4 %. Polyphasic taxonomic evidence indicated that strain A1-17BT should be categorized together with the unofficially named Rothia dentocariosa genomovar II, but clearly differentiated them from the established species of the genus Rothia. Strain A1-22T formed a coherent cluster with Rhodococcus erythropolis, Rhodococcus globerulus, Rhodococcus marinonascens and Rhodococcus percolatus in 16S rDNA sequence analysis, but DNA–DNA relatedness values were only 45·5, 35·3, 18·9 and 21·9 %. Strains A1-3T and A1-8 shared 99·9 % 16S rDNA sequence similarity, and strain A1-3T showed the highest level of 16S rDNA similarity, 96·6 %, to Arthrobacter polychromogenes. Contrasting biochemical characteristics were also identified. Finally, as a result of the polyphasic taxonomic study, three of the strains are proposed as type strains of novel species: Rothia aeria sp. nov. (A1-17BT=GTC 867T=JCM 11412T=DSM 14556T), Rhodococcus baikonurensis sp. nov. (A1-22T=GTC 1041T=JCM 11411T=DSM 44587T) and Arthrobacter russicus sp. nov. (A1-3T=GTC 863T=JCM 11414T=DSM 14555T).
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Affiliation(s)
- Ying Li
- Department of Microbiology - Bioinformatics, Regeneration and Advanced Medical Science, Gifu University, Graduate School of Medicine, Tsukasa-machi 40, Gifu 500-8705, Japan
| | - Yoshiaki Kawamura
- Department of Microbiology - Bioinformatics, Regeneration and Advanced Medical Science, Gifu University, Graduate School of Medicine, Tsukasa-machi 40, Gifu 500-8705, Japan
| | - Nagatoshi Fujiwara
- Department of Bacteriology, Osaka City University, Medical School, Abeno-ku, Osaka 545-8585, Japan
| | - Takashi Naka
- Department of Bacteriology, Osaka City University, Medical School, Abeno-ku, Osaka 545-8585, Japan
| | - Hongsheng Liu
- Department of Microbiology - Bioinformatics, Regeneration and Advanced Medical Science, Gifu University, Graduate School of Medicine, Tsukasa-machi 40, Gifu 500-8705, Japan
| | - Xinxiang Huang
- Department of Microbiology - Bioinformatics, Regeneration and Advanced Medical Science, Gifu University, Graduate School of Medicine, Tsukasa-machi 40, Gifu 500-8705, Japan
| | - Kazuo Kobayashi
- Department of Bacteriology, Osaka City University, Medical School, Abeno-ku, Osaka 545-8585, Japan
| | - Takayuki Ezaki
- Department of Microbiology - Bioinformatics, Regeneration and Advanced Medical Science, Gifu University, Graduate School of Medicine, Tsukasa-machi 40, Gifu 500-8705, Japan
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Abstract
We had the opportunity to investigate the bacterial population in air samples, condensation water, and inner wall swabs from the Russian space station Mir. From the first and second air samples during the mission, 29 and 7 bacterial colonies were collected, respectively. The values were equivalent to 16.8 and 4.0 cfu/100 liter air, respectively. Condensation water was collected from three different sites. The total viable bacterial counts were 2.1 x 10(6), 5.2 x 10(2), and 3.0 x 10(1) cfu/ml. The phylogenetic position of each isolate was determined by total 16S rDNA sequencing. Bacteria from air samples were mainly Gram-positive (35/36 colonies), and staphylococci occupied dominant specifically (23/36 colonies). On the other hand, Gram-negative bacteria were mainly isolated from condensation water samples. Most strains were thought to be opportunistic pathogens or environmental bacteria (such as those that inhabit soil, water, or air) found on earth. However, 6 of 23 isolates were suspected to be new species according to phylogenetic analysis and quantitative DNA-DNA hybridization data. The isolation of the other levels 3 and 2 bacteria, using specific selective media, was unsuccessful because all samples were heavily contaminated with fungi. To overcome this situation, PCR methods were applied to survey most levels 3 and 2 pathogenic bacteria in the condensation water samples. Up to 380 different primers for bacterial pathogens were used in this study. Only Mycobacterium avium 16S DNA sequences, however, could be amplified from the three water samples. The average bacteria count was estimated to be about 10(4) organisms/ml water.
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Affiliation(s)
- Y Kawamura
- Department of Microbiology, Gifu University School of Medicine, Gifu, Japan.
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Taylor GR, Kropp KD, Molina TC. Nine-year microflora study of an isolator-maintained immunodeficient child. Appl Environ Microbiol 1985; 50:1349-56. [PMID: 4091564 PMCID: PMC238762 DOI: 10.1128/aem.50.6.1349-1356.1985] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
A male child, maintained in a controlled environment, was monitored each month for bacteria, yeasts, and filamentous fungi recovered from the mouth, nasal passages, feces, and nine body surface sites. Three natural microbial categories became apparent. Incident microorganisms were recovered from within the isolator but did not establish permanent residence. Of the 53 incident types isolated, 20 were filamentous fungi and 4 were yeasts. Some genera, such as Fusobacterium, Lactobacillus, Neisseria, and Rothia, which were commonly found in the reference group, did not become permanent inhabitants. Transient microorganisms were repeatedly recovered but could not be demonstrated within the isolated environment at the end of the study. The loss of only a few of the 19 transient species could be associated with antimicrobial therapy. Permanent microorganisms consisted of Pencillium citrinum and 17 bacterial types, of which alpha-hemolytic streptococci, Staphylococcus edpidermidis subgroups II and V, Micrococcus groups 1 and 2, Clostridium bifermentans, and Propionibacterium acnes were recovered throughout the entire 9 years of the study. The number of CFUs recovered from each sample type was generally not unlike that from the reference group of healthy male adults. Also, the number of different aerobic species recovered from the feces was within the normal range of that of the reference group. In contrast, the number of different species recovered from all other samples was less than that commonly found in the reference group.
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25
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Balish E, Cleven D, Brown J, Yale CE. Nose, throat, and fecal flora of beagle dogs housed in "locked" or "open" environments. Appl Environ Microbiol 1977; 34:207-21. [PMID: 907342 PMCID: PMC242622 DOI: 10.1128/aem.34.2.207-221.1977] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The microbial flora of the nose, throat, and feces of male beagle dogs housed in a "locked environment" (i.e. confined to germfree-style isolators and supplied with sterile food, air, and water) or an open environment were assessed between 26 and 30 months into the study. Forty-five genera and 170 different species or types of microorganisms were cultured from the nose, throat, and feces of the beagles. Clostridia, eubacteria, corynebacteria, bacteroides, lactobacilli, and anaerobic, gram-positive cocci accounted for most of the microbial diversity in the flora. Some of the facultative anaerobes, especially streptococci and lactobacilli (in feces), occurred in numbers that were comparable to the most numerous anaerobic species. Confinement to the locked environment resulted in an increased diversity of microorganisms in the flora, but the total microbial counts did not increase to any great extent. Even with the increased diversity of bacteria in the flora of confined dogs, some bacteria seemed to favor certain areas of the gastrointestinal tract over others. The increased diversity of bacteria observed in these confined dogs may pose some infectious disease problems for other mammals (including humans) that may be confined to a locked, ultra-clean environment for a prolonged period of time.
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Carmichael C, Taylor GR. Evaluation of crew skin flora under conditions of a full quarantine lunar-exploration mission. Br J Dermatol 1977; 97:187-96. [PMID: 911680 DOI: 10.1111/j.1365-2133.1977.tb15064.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Crew-members of the Apollo 14 lunar exploration mission underwent a pre-flight seclusion designed to stabilize their health by freeing them from exposure to potentially infectious agents. After the flight, the crew-members were quarantined to protect the biosphere from possible lunar contamination. These isolations, along with the complete isolation of the spaceflight itself, provided the opportunity for a skin flora survey which included the sampling of seven sites at five different times. Quantification and identification of all aerobic and anaerobic bacteria from each site were performed. The results indicated that the pre-flight quarantine measures resulted in a decrease in total numbers of isolates as well as a decrease in the anaerobes. This was followed by a continued decrease throughout the flight with a return to the pre-flight norm within 16 days after the flight. The quantitative load of aerobic bacteria increased during the flight, due largely to an increase in coryneforms and micrococcaceae. The quantitative load of anaerobic bacteria decreased before and during the flight. No instance of microbial shock or intercrew transfer of micro-organisms was demonstrated. These findings indicate that alterations in the skin flora do not pose any unusual problem during short duration space flights. Further, there are no indications that problems will arise on longer missions.
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