Effect of spaceflight on Pseudomonas aeruginosa final cell density is modulated by nutrient and oxygen availability

BMC Microbiology

Cynthia H Collins⁴  Joel L Plawsky¹  Jonathan S Dordick⁴  Macarena Parra²  Ravindra C Pangule⁵  Zachary Young¹  Hon Kit Chan³  Nicholas Marchand³  Jasmine Shong³  Farah K Tengra³  Wooseong Kim³ 

[1]Department of Chemical & Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA

[2]Lockheed Martin-Ames Research Center, Moffett Field, CA 94035, USA

[3]Center for Biotechnology and Interdisciplinary Studies (CBIS), Rensselaer Polytechnic Institute, Troy, NY 12180, USA

[4]Department of Biology, Rensselaer Polytechnic Institute, Troy, NY 12180, USA

[5]Current address: Regeneron Pharmaceuticals Inc., Rensselaer, NY 12144, USA

关键词: Motility;    Flow cytometry;    Pseudomonas aeruginosa;    Microgravity;    Spaceflight;   

Others  :  1142777
DOI  :  10.1186/1471-2180-13-241

 received in 2013-06-04, accepted in 2013-10-15,  发布年份 2013

【 摘 要 】

Background

Abundant populations of bacteria have been observed on Mir and the International Space Station. While some experiments have shown that bacteria cultured during spaceflight exhibit a range of potentially troublesome characteristics, including increases in growth, antibiotic resistance and virulence, other studies have shown minimal differences when cells were cultured during spaceflight or on Earth. Although the final cell density of bacteria grown during spaceflight has been reported for several species, we are not yet able to predict how different microorganisms will respond to the microgravity environment. In order to build our understanding of how spaceflight affects bacterial final cell densities, additional studies are needed to determine whether the observed differences are due to varied methods, experimental conditions, or organism specific responses.

Results

Here, we have explored how phosphate concentration, carbon source, oxygen availability, and motility affect the growth of Pseudomonas aeruginosa in modified artificial urine media during spaceflight. We observed that P. aeruginosa grown during spaceflight exhibited increased final cell density relative to normal gravity controls when low concentrations of phosphate in the media were combined with decreased oxygen availability. In contrast, when the availability of either phosphate or oxygen was increased, no difference in final cell density was observed between spaceflight and normal gravity. Because motility has been suggested to affect how microbes respond to microgravity, we compared the growth of wild-type P. aeruginosa to a ΔmotABCD mutant deficient in swimming motility. However, the final cell densities observed with the motility mutant were consistent with those observed with wild type for all conditions tested.

Conclusions

These results indicate that differences in bacterial final cell densities observed between spaceflight and normal gravity are due to an interplay between microgravity conditions and the availability of substrates essential for growth. Further, our results suggest that microbes grown under nutrient-limiting conditions are likely to reach higher cell densities under microgravity conditions than they would on Earth. Considering that the majority of bacteria inhabiting spacecrafts and space stations are likely to live under nutrient limitations, our findings highlight the need to explore the impact microgravity and other aspects of the spaceflight environment have on microbial growth and physiology.

【 授权许可】

   
2013 Kim et al.; licensee BioMed Central Ltd.

【 图 表 】

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【 参考文献 】

• [1]Benoit MR, Brown RB, Todd P, Nelson ES, Klaus DM: Buoyant plumes from solute gradients generated by non-motile Escherichia coli. Phys Biol 2008, 5:046007.
• [2]Nelson ES, Jules K: The microgravity environment for experiments on the International Space Station. J Gravit Physiol 2004, 11:1-10.
• [3]Horneck G, Klaus DM, Mancinelli RL: Space microbiology. Microbiol Mol Biol Rev 2010, 74:121-156.
• [4]Bouloc P, D’Ari R: Escherichia coli metabolism in space. J Gen Microbiol 1991, 137:2839-2843.
• [5]Brown RB, Klaus D, Todd P: Effects of space flight, clinorotation, and centrifugation on the substrate utilization efficiency of E. coli. Microgravity Sci Technol 2002, 13:24-29.
• [6]Gasset G, Tixador R, Eche B, Lapchine L, Moatti N, Toorop P, Woldringh C: Growth and division of Escherichia coli under microgravity conditions. Res Microbiol 1994, 145:111-120.
• [7]Kacena MA, Manfredi B, Todd P: Effects of space flight and mixing on bacterial growth in low volume cultures. Microgravity Sci Technol 1999, 12:74-77.
• [8]Klaus D, Simske S, Todd P, Stodieck L: Investigation of space flight effects on Escherichia coli and a proposed model of underlying physical mechanisms. Microbiology 1997, 143:449-455.
• [9]Thévenet D, D’Ari R, Bouloc P: The SIGNAL experiment in BIORACK: Escherichia coli in microgravity. J Biotechnol 1996, 47:89-97.
• [10]Mennigmann HD, Lange M: Growth and differentiation of Bacillus subtilis under microgravity. Naturwissenschaften 1986, 73:415-417.
• [11]Menningmann HD, Heise M: Fifth European Symposium on Life Sciences Research in Space. Arcachon, France: European Space Agency (ESA); 1994:88-87. [Response of growing bacteria to reduction in gravity]
• [12]Mattoni RHT: Space-flight effects and gamma radiation interaction on growth and induction of lysogenic bacteria. Bioscience 1968, 18:602-608.
• [13]Wilson JW, Ott CM, Honer zu Bentrup K, Ramamurthy R, Quick L, Porwollik S, Cheng P, McClelland M, Tsaprailis G, Radabaugh T, et al.: Space flight alters bacterial gene expression and virulence and reveals a role for global regulator Hfq. Proc Natl Acad Sci USA 2007, 104:16299-16304.
• [14]Benoit MR, Klaus DM: Microgravity, bacteria, and the influence of motility. Adv Space Res 2007, 39:1225-1232.
• [15]Wilson JW, Ott CM, Quick L, Davis R, Höner zu Bentrup K, Crabbé A, Richter E, Sarker S, Barrila J, Porwollik S, et al.: Media ion composition controls regulatory and virulence response of Salmonella in spaceflight. PLoS One 2008, 3:e3923.
• [16]Crabbé A, Pycke B, Van Houdt R, Monsieurs P, Nickerson C, Leys N, Cornelis P: Response of Pseudomonas aeruginosa PAO1 to low shear modelled microgravity involves AlgU regulation. Environ Microbiol 2010, 12:1545-1564.
• [17]Crabbé A, Schurr MJ, Monsieurs P, Morici L, Schurr J, Wilson JW, Ott CM, Tsaprailis G, Pierson DL, Stefanyshyn-Piper H, et al.: Transcriptional and proteomic responses of Pseudomonas aeruginosa PAO1 to spaceflight conditions involve Hfq regulation and reveal a role for oxygen. Appl Environ Microbiol 2011, 77:1221-1230.
• [18]Hong CS, Shitashiro M, Kuroda A, Ikeda T, Takiguchi N, Ohtake H, Kato J: Chemotaxis proteins and transducers for aerotaxis in Pseudomonas aeruginosa. FEMS Microbiol Lett 2004, 231:247-252.
• [19]Schertzer JW, Brown SA, Whiteley M: Oxygen levels rapidly modulate Pseudomonas aeruginosa social behaviours via substrate limitation of PqsH. Mol Microbiol 2010, 77:1527-1538.
• [20]Xu KD, Stewart PS, Xia F, Huang CT, McFeters GA: Spatial physiological heterogeneity in Pseudomonas aeruginosa biofilm is determined by oxygen availability. Appl Environ Microbiol 1998, 64:4035-4039.
• [21]Taylor GR: Recovery of medically important microorganisms from Apollo astronauts. Aerosp Med 1974, 45:824-828.
• [22]Sonnenfeld G: The immune system in space, including Earth-based benefits of space-based research. Curr Pharm Biotechnol 2005, 6:343-349.
• [23]Rahme LG, Stevens EJ, Wolfort SF, Shao J, Tompkins RG, Ausubel FM: Common virulence factors for bacterial pathogenicity in plants and animals. Science 1995, 268:1899-1902.
• [24]Kim W, Tengra FK, Young Z, Shong J, Marchand N, Chan HK, Rangule R, Parra M, Dordick JS, Plawsky JL, et al.: Spaceflight promotes biofilm formation by Pseudomonas aeruginosa. PLoS One 2013, 8:e62437.
• [25]Holloway BW: Genetic recombination in Pseudomonas aeruginosa. J Gen Microbiol 1955, 13:572-581.
• [26]He J, Baldini RL, Deziel E, Saucier M, Zhang Q, Liberati NT, Lee D, Urbach J, Goodman HM, Rahme LG: The broad host range pathogen Pseudomonas aeruginosa strain PA14 carries two pathogenicity islands harboring plant and animal virulence genes. Proc Natl Acad Sci USA 2004, 101:2530-2535.
• [27]Lynch SVM: Travails of microgravity: man and microbes in space. Biologist 2005, 52:80-87.
• [28]Kacena MT, Todd P: Growth characteristics of E. coli and B. subtilis cultured on an agar substrate in microgravity. Microgravity Sci Technol 1997, 10:58-62.
• [29]Davey HM: Flow cytometric techniques for the detection of microorganisms. Methods Cell Sci 2002, 24:91-97.
• [30]Lam KS, Mamber SW, Pack EJ, Forenza S, Fernandes PB, Klaus DM: The effects of space flight on the production of monorden by Humicola fuscoatra WC5157 in solid-state fermentation. Appl Microbiol Biotechnol 1998, 49:579-583.
• [31]Brooks T, Keevil CW: A simple artificial urine for the growth of urinary pathogens. Lett Appl Microbiol 1997, 24:203-206.
• [32]Chutipongtanate S, Thongboonkerd V: Systematic comparisons of artificial urine formulas for in vitro cellular study. Anal Biochem 2010, 402:110-112.
• [33]Bussolati G, Annaratone L, Medico E, D’Armento G, Sapino A: Formalin fixation at low temperature better preserves nucleic acid integrity. PLoS One 2011, 6:e21043.
• [34]Patterson TE, Jackson H: Effect of storage at 1 degree and 4 degrees C on viability and injury of Staphylococcus aureus, Escherichia coli and Streptococcus faecalis. J Appl Bacteriol 1979, 46:161-167.
• [35]Pye A, Hill SL, Bharadwa P, Stockley RA: Effect of storage and postage on recovery and quantitation of bacteria in sputum samples. J Clin Pathol 2008, 61:352-354.
• [36]Ng FM, Dawes EA: Chemostat studies on the regulation of glucose metabolism in Pseudomonas aeruginosa by citrate. Biochem J 1973, 132:129-140.
• [37]Nishijyo T, Haas D, Itoh Y: The CbrA-CbrB two-component regulatory system controls the utilization of multiple carbon and nitrogen sources in Pseudomonas aeruginosa. Mol Microbiol 2001, 40:917-931.
• [38]Frimmersdorf E, Horatzek S, Pelnikevich A, Wiehlmann L, Schomburg D: How Pseudomonas aeruginosa adapts to various environments: a metabolomic approach. Environ Microbiol 2010, 12:1734-1747.
• [39]Hoehn A, Klaus DM, Stodieck LS: A modular suite of hardware enabling spaceflight cell culture research. J Gravit Physiol 2004, 11:39-49.
• [40]Toutain CM, Zegans ME, O’Toole GA: Evidence for two flagellar stators and their role in the motility of Pseudomonas aeruginosa. J Bacteriol 2005, 187:771-777.
• [41]Crabbé A, De Boever P, Van Houdt R, Moors H, Mergeay M, Cornelis P: Use of the rotating wall vessel technology to study the effect of shear stress on growth behaviour of Pseudomonas aeruginosa PAO1. Environ Microbiol 2008, 10:2098-2110.
• [42]Mauclaire L, Egli M: Effect of simulated microgravity on growth and production of exopolymeric substances of Micrococcus luteus space and earth isolates. FEMS Immuno Med Microbiol 2010, 59:350-356.
• [43]Castro SL, Nelman-Gonzalez M, Nickerson CA, Ott CM: Induction of attachment-independent biofilm formation and repression of Hfq expression by low-fluid-shear culture of Staphylococcus aureus. Appl Environ Microbiol 2011, 77:6368-6378.
• [44]Berry D, Volz PA: Phosphate uptake in Saccharomyces cerevisiae Hansen wild type and phenotypes exposed to space flight irradiation. Appl Environ Microbiol 1979, 38:751-753.
• [45]Bains M, Fernandez L, Hancock RE: Phosphate starvation promotes swarming motility and cytotoxicity of Pseudomonas aeruginosa. Appl Environ Microbiol 2012, 78:6762-6768.
• [46]Amsler CD, Cho M, Matsumura P: Multiple factors underlying the maximum motility of Escherichia coli as cultures enter post-exponential growth. J Bacteriol 1993, 175:6238-6244.
• [47]Arora S, Bhat V, Mittal A: Correlating single cell motility with population growth dynamics for flagellated bacteria. Biotechnol Bioeng 2007, 97:1644-1649.
• [48]Hall-Stoodley L, Costerton JW, Stoodley P: Bacterial biofilms: from the natural environment to infectious diseases. Nat Rev Microbiol 2004, 2:95-108.
• [49]Stoodley P, Sauer K, Davies DG, Costerton JW: Biofilms as complex differentiated communities. Annu Rev Microbiol 2002, 56:187-209.
• [50]Colvin KM, Gordon VD, Murakami K, Borlee BR, Wozniak DJ, Wong GCL, Parsek MR: The Pel polysaccharide can serve a structural and protective role in the biofilm matrix of Pseudomonas aeruginosa. Plos Pathogens 2011, 7:e1001264.