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Robinson RE, Robertson JK, Moustafa DA, Goldberg JB. piv does not impact Pseudomonas aeruginosa virulence in Galleria mellonella. Microbiol Spectr 2025:e0281124. [PMID: 40396793 DOI: 10.1128/spectrum.02811-24] [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: 11/02/2024] [Accepted: 03/28/2025] [Indexed: 05/22/2025] Open
Abstract
Pseudomonas aeruginosa is an opportunistic human pathogen that can also infect mammals, invertebrates, and plants. Protease IV (PIV) is a secreted protease shown to be important in mammalian cornea, lung, and wound models of infection. It also contributes to P. aeruginosa virulence in many invertebrate models. Previous studies have shown that the expression of the gene encoding PIV is higher at 25°C than at 37°C. Thus, we hypothesized that piv would be more important for P. aeruginosa virulence at 25°C than at 37°C. To test this, we first demonstrated that more PIV is secreted by P. aeruginosa PAO1 cells grown at 25°C than at 37°C. We then determined the survival of larvae of the greater wax moth Galleria mellonella infected by PAO1 and an isogenic Δpiv mutant at both 25°C and 37°C. We found no significant difference in virulence between PAO1 and Δpiv at either 25°C or 37°C, although both strains were more virulent at 37°C than 25°C as measured by a decrease in median survival time. P. aeruginosa possesses an arsenal of virulence factors besides PIV, and thus loss of this single virulence factor may not result in attenuation in the highly susceptible G. mellonella larvae.IMPORTANCEPathogenesis of the important opportunistic pathogen Pseudomonas aeruginosa is often investigated using model organisms. Larvae of the greater wax moth, Galleria mellonella, are a popular non-mammalian model organism for P. aeruginosa infections that have been used to study highly attenuated mutants and characterize their defects in virulence. Our study shows that small differences in the virulence of P. aeruginosa, such as those caused by deleting the gene encoding a single virulence factor, may not be detectable in the G. mellonella model of infection. This is an important finding for researchers considering the choice of model organisms for virulence studies.
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Affiliation(s)
- Rachel E Robinson
- Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, Georgia, USA
- Department of Pediatrics, Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Emory University School of Medicine, Atlanta, Georgia, USA
| | | | - Dina A Moustafa
- Department of Pediatrics, Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory+Children's Center for Cystic Fibrosis and Airway Disease Research, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Joanna B Goldberg
- Department of Pediatrics, Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory+Children's Center for Cystic Fibrosis and Airway Disease Research, Emory University School of Medicine, Atlanta, Georgia, USA
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Robinson RE, Robertson JK, Prezioso SM, Goldberg JB. Temperature controls LasR regulation of piv expression in Pseudomonas aeruginosa. mBio 2025:e0054125. [PMID: 40391957 DOI: 10.1128/mbio.00541-25] [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: 02/19/2025] [Accepted: 04/15/2025] [Indexed: 05/22/2025] Open
Abstract
The opportunistic pathogen Pseudomonas aeruginosa causes debilitating lung infections in people with cystic fibrosis, as well as eye, burn, and wound infections in otherwise immunocompetent individuals. Many of P. aeruginosa's virulence factors are regulated by environmental cues, such as temperature and cell density. One such virulence factor is protease IV. Prior studies have shown that piv expression is higher at ambient temperatures (22°C-28°C) compared to human body temperature (37°C) and also upregulated by the LasRI quorum sensing system, although it is unclear how. We found that piv expression was thermoregulated at stationary phase, but not exponential phase, and that piv is thermoregulated at the level of transcription. Using a transcriptional reporter for piv, we show that LasR activates piv expression more at 25°C at stationary phase than at 37°C. We show that key components of the LasRI quorum sensing system are not upregulated at 25°C, suggesting that LasR regulatory activity is not higher intrinsically at this temperature. We also identified sequences within the piv promoter that are important for its thermoregulation. We propose that LasR upregulates piv more at 25°C than at 37°C. The finding that temperature controls LasR regulation of piv highlights the complex nature of gene regulatory systems in P. aeruginosa.IMPORTANCEPseudomonas aeruginosa is a versatile opportunistic pathogen capable of causing many different types of infections that are often difficult to treat, such as lung infections in people with cystic fibrosis. Temperature regulates the expression of many virulence factors that contribute to P. aeruginosa's ability to cause infection, yet our mechanistic understanding of virulence factor thermoregulation is poor. In this study, we show that the virulence factor protease IV is thermoregulated at the level of transcription through the quorum sensing regulator, LasR. Mechanistic studies of virulence factor thermoregulation will expand our understanding of how P. aeruginosa experiences different environments, including the mammalian host. Our work also highlights the importance of growth conditions in studying gene regulation, as it better elucidates the regulation of protease IV by LasR, which was previously not well understood.
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Affiliation(s)
- Rachel E Robinson
- Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, Georgia, USA
- Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
| | | | - Samantha M Prezioso
- Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, Georgia, USA
- Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Joanna B Goldberg
- Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory+Children's Center for Cystic Fibrosis and Airway Disease Research, Emory University School of Medicine, Atlanta, Georgia, USA
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Ábrahám Á, Dér L, Csákvári E, Vizsnyiczai G, Pap I, Lukács R, Varga-Zsíros V, Nagy K, Galajda P. Single-cell level LasR-mediated quorum sensing response of Pseudomonas aeruginosa to pulses of signal molecules. Sci Rep 2024; 14:16181. [PMID: 39003361 PMCID: PMC11246452 DOI: 10.1038/s41598-024-66706-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 07/03/2024] [Indexed: 07/15/2024] Open
Abstract
Quorum sensing (QS) is a communication form between bacteria via small signal molecules that enables global gene regulation as a function of cell density. We applied a microfluidic mother machine to study the kinetics of the QS response of Pseudomonas aeruginosa bacteria to additions and withdrawals of signal molecules. We traced the fast buildup and the subsequent considerably slower decay of a population-level and single-cell-level QS response. We applied a mathematical model to explain the results quantitatively. We found significant heterogeneity in QS on the single-cell level, which may result from variations in quorum-controlled gene expression and protein degradation. Heterogeneity correlates with cell lineage history, too. We used single-cell data to define and quantitatively characterize the population-level quorum state. We found that the population-level QS response is well-defined. The buildup of the quorum is fast upon signal molecule addition. At the same time, its decay is much slower following signal withdrawal, and the quorum may be maintained for several hours in the absence of the signal. Furthermore, the quorum sensing response of the population was largely repeatable in subsequent pulses of signal molecules.
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Affiliation(s)
- Ágnes Ábrahám
- HUN-REN Biological Research Centre, Institute of Biophysics, Temesvári Krt. 62, Szeged, 6726, Hungary
- Doctoral School of Multidisciplinary Medical Sciences, University of Szeged, Dóm Tér 9, Szeged, 6720, Hungary
| | - László Dér
- HUN-REN Biological Research Centre, Institute of Biophysics, Temesvári Krt. 62, Szeged, 6726, Hungary
| | - Eszter Csákvári
- HUN-REN Biological Research Centre, Institute of Biophysics, Temesvári Krt. 62, Szeged, 6726, Hungary
- Division for Biotechnology, Bay Zoltán Nonprofit Ltd. for Applied Research, Derkovits Fasor 2., Szeged, 6726, Hungary
| | - Gaszton Vizsnyiczai
- HUN-REN Biological Research Centre, Institute of Biophysics, Temesvári Krt. 62, Szeged, 6726, Hungary
| | - Imre Pap
- HUN-REN Biological Research Centre, Institute of Biophysics, Temesvári Krt. 62, Szeged, 6726, Hungary
- Doctoral School of Multidisciplinary Medical Sciences, University of Szeged, Dóm Tér 9, Szeged, 6720, Hungary
| | - Rebeka Lukács
- HUN-REN Biological Research Centre, Institute of Biophysics, Temesvári Krt. 62, Szeged, 6726, Hungary
| | - Vanda Varga-Zsíros
- HUN-REN Biological Research Centre, Institute of Biophysics, Temesvári Krt. 62, Szeged, 6726, Hungary
- HUN-REN Biological Research Centre, Institute of Biochemistry, Temesvári Krt. 62, Szeged, 6726, Hungary
| | - Krisztina Nagy
- HUN-REN Biological Research Centre, Institute of Biophysics, Temesvári Krt. 62, Szeged, 6726, Hungary.
| | - Péter Galajda
- HUN-REN Biological Research Centre, Institute of Biophysics, Temesvári Krt. 62, Szeged, 6726, Hungary.
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Done RE, Robertson JK, Prezioso SM, Goldberg JB. LasR regulates protease IV expression at suboptimal growth temperatures in Pseudomonas aeruginosa. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.27.601069. [PMID: 38979315 PMCID: PMC11230357 DOI: 10.1101/2024.06.27.601069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
The opportunistic pathogen Pseudomonas aeruginosa causes debilitating lung infections in people with cystic fibrosis, as well as eye, burn, and wound infections in otherwise immunocompetent individuals. Many of P. aeruginosa's virulence factors are regulated by environmental changes associated with human infection, such as a change in temperature from ambient to human body temperature. One such virulence factor is protease IV (PIV). Interestingly, piv expression is higher at ambient temperatures (22-28°C) compared to human body temperature (37°C). We found that piv expression was thermoregulated at stationary phase, but not exponential phase, and that piv is thermoregulated at the level of transcription. Protein levels of known transcriptional regulators of piv, the quorum sensing regulator LasR and the gene-silencing histone nucleoid silencing proteins MvaT/MvaU, were not thermoregulated. Using a transcriptional reporter for piv, we show that LasR activates piv expression at stationary phase at 25°C but not 37°C, while MvaT/MvaU are not required for piv thermoregulation. We also identified a las box in the piv promoter, which is important for piv thermoregulation. We propose that LasR directly regulates piv at stationary phase at 25°C but has a negligible impact at 37°C. Here, we show that piv is uniquely regulated by LasR in a temperature-dependent manner. Our findings suggest that the LasRI quorum sensing regulon of P. aeruginosa may not be fully characterized and that growth at non-standard laboratory conditions such as lower temperatures could reveal previously unrecognized quorum sensing regulated genes.
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Affiliation(s)
- Rachel E. Done
- Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, Georgia, USA
- Department of Pediatrics, Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Emory University School of Medicine, Atlanta, Georgia, USA
| | | | - Samantha M. Prezioso
- Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, Georgia, USA
- Department of Pediatrics, Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Joanna B. Goldberg
- Department of Pediatrics, Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Emory University School of Medicine, Atlanta, Georgia, USA
- Emory+Children’s Center for Cystic Fibrosis and Airway Disease Research, Emory University School of Medicine, Atlanta, Georgia, USA
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5
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Nishiyama Y, Mizutani A, Kobayashi M, Muranaka Y, Sato K, Maki H, Kawai K. SPECT Imaging of P. aeruginosa Infection in Mice Using 123I-BMIPP. Pharmaceutics 2024; 16:656. [PMID: 38794318 PMCID: PMC11124952 DOI: 10.3390/pharmaceutics16050656] [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: 04/11/2024] [Revised: 05/10/2024] [Accepted: 05/14/2024] [Indexed: 05/26/2024] Open
Abstract
Pseudomonas aeruginosa infection is an infectious disease that must be controlled because it becomes chronic and difficult to treat, owing to its unique system of toxin production/injection and elimination of other bacteria. Here, we noninvasively monitored P. aeruginosa using single-photon emission computed tomography (SPECT) imaging. Determining the amount and localization of the P. aeruginosa will enable making faster clinical diagnoses and selecting the most appropriate therapeutic agents and methods. Nonclinically, this information can be used for imaging in combination with biofilms and toxin probes and will be useful for discovering drugs targeting P. aeruginosa. To study P. aeruginosa accumulation, we conducted in vitro and in vivo studies using iodine-123 β-methyl-p-iodophenyl-pentadecanoic acid (123I-BMIPP), which we previously reported using for Escherichia coli. In vitro, 123I-BMIPP accumulated in P. aeruginosa by being taken up into the bacteria and adsorbing to the bacterial surface. In vivo, 123I-BMIPP accumulated significantly more in infected sites than in noninfected sites and could be quantified by SPECT. These results suggest that 123I-BMIPP can be used as a probe for P. aeruginosa for SPECT. Establishing a noninvasive monitoring method using SPECT will allow further progress in studying P. aeruginosa.
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Affiliation(s)
- Yuri Nishiyama
- Division of Health Sciences, Graduate School of Medical Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa 920-0942, Japan; (Y.N.); (K.S.)
- Laboratory for Drug Discovery & Disease Research, Shionogi & Co., Ltd., 3-1-1 Futaba-cho, Toyonaka 561-0825, Japan;
| | - Asuka Mizutani
- Faculty of Health Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa 920-0942, Japan; (A.M.); (M.K.)
| | - Masato Kobayashi
- Faculty of Health Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa 920-0942, Japan; (A.M.); (M.K.)
| | - Yuka Muranaka
- Department of Radiological Technology, Faculty of Health Science, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan;
| | - Kakeru Sato
- Division of Health Sciences, Graduate School of Medical Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa 920-0942, Japan; (Y.N.); (K.S.)
| | - Hideki Maki
- Laboratory for Drug Discovery & Disease Research, Shionogi & Co., Ltd., 3-1-1 Futaba-cho, Toyonaka 561-0825, Japan;
| | - Keiichi Kawai
- Faculty of Health Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa 920-0942, Japan; (A.M.); (M.K.)
- Biomedical Imaging Research Center, University of Fukui, 23-3 Matsuoka-shimoaizuki, Eiheiji-cho, Yoshida-gun, Fukui 910-1193, Japan
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Solar Venero EC, Galeano MB, Luqman A, Ricardi MM, Serral F, Fernandez Do Porto D, Robaldi SA, Ashari BAZ, Munif TH, Egoburo DE, Nemirovsky S, Escalante J, Nishimura B, Ramirez MS, Götz F, Tribelli PM. Fever-like temperature impacts on Staphylococcus aureus and Pseudomonas aeruginosa interaction, physiology, and virulence both in vitro and in vivo. BMC Biol 2024; 22:27. [PMID: 38317219 PMCID: PMC10845740 DOI: 10.1186/s12915-024-01830-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 01/18/2024] [Indexed: 02/07/2024] Open
Abstract
BACKGROUND Staphylococcus aureus (SA) and Pseudomonas aeruginosa (PA) cause a wide variety of bacterial infections and coinfections, showing a complex interaction that involves the production of different metabolites and metabolic changes. Temperature is a key factor for bacterial survival and virulence and within the host, bacteria could be exposed to an increment in temperature during fever development. We analyzed the previously unexplored effect of fever-like temperatures (39 °C) on S. aureus USA300 and P. aeruginosa PAO1 microaerobic mono- and co-cultures compared with 37 °C, by using RNAseq and physiological assays including in vivo experiments. RESULTS In general terms both temperature and co-culturing had a strong impact on both PA and SA with the exception of the temperature response of monocultured PA. We studied metabolic and virulence changes in both species. Altered metabolic features at 39 °C included arginine biosynthesis and the periplasmic glucose oxidation in S. aureus and P. aeruginosa monocultures respectively. When PA co-cultures were exposed at 39 °C, they upregulated ethanol oxidation-related genes along with an increment in organic acid accumulation. Regarding virulence factors, monocultured SA showed an increase in the mRNA expression of the agr operon and hld, pmsα, and pmsβ genes at 39 °C. Supported by mRNA data, we performed physiological experiments and detected and increment in hemolysis, staphyloxantin production, and a decrease in biofilm formation at 39 °C. On the side of PA monocultures, we observed an increase in extracellular lipase and protease and biofilm formation at 39 °C along with a decrease in the motility in correlation with changes observed at mRNA abundance. Additionally, we assessed host-pathogen interaction both in vitro and in vivo. S. aureus monocultured at 39οC showed a decrease in cellular invasion and an increase in IL-8-but not in IL-6-production by A549 cell line. PA also decreased its cellular invasion when monocultured at 39 °C and did not induce any change in IL-8 or IL-6 production. PA strongly increased cellular invasion when co-cultured at 37 and 39 °C. Finally, we observed increased lethality in mice intranasally inoculated with S. aureus monocultures pre-incubated at 39 °C and even higher levels when inoculated with co-cultures. The bacterial burden for P. aeruginosa was higher in liver when the mice were infected with co-cultures previously incubated at 39 °C comparing with 37 °C. CONCLUSIONS Our results highlight a relevant change in the virulence of bacterial opportunistic pathogens exposed to fever-like temperatures in presence of competitors, opening new questions related to bacteria-bacteria and host-pathogen interactions and coevolution.
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Affiliation(s)
- E C Solar Venero
- Instituto De Química Biológica de La Facultad de Ciencias Exactas y Naturales-CONICET, Buenos Aires, Argentina
- Present addressDepartment of BiochemistrySchool of Medicine, Universidad Autónoma de Madrid and Instituto de Investigaciones Biomédicas Alberto Sols (Universidad Autónoma de Madrid-Consejo Superior de Investigaciones Científicas), Madrid, Spain
| | - M B Galeano
- Instituto De Química Biológica de La Facultad de Ciencias Exactas y Naturales-CONICET, Buenos Aires, Argentina
| | - A Luqman
- Department of Biology, Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia
| | - M M Ricardi
- IFIBYNE (UBA-CONICET), FBMC, FCEyN-UBA, Buenos Aires, Argentina
| | - F Serral
- Instituto del Calculo-UBA-CONICET, Buenos Aires, Argentina
| | | | - S A Robaldi
- Departamento de Química Biológica, FCEyN-UBA, Buenos Aires, Argentina
| | - B A Z Ashari
- Department of Biology, Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia
| | - T H Munif
- Department of Biology, Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia
| | - D E Egoburo
- Departamento de Química Biológica, FCEyN-UBA, Buenos Aires, Argentina
| | - S Nemirovsky
- Instituto De Química Biológica de La Facultad de Ciencias Exactas y Naturales-CONICET, Buenos Aires, Argentina
| | - J Escalante
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA, USA
| | - B Nishimura
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA, USA
| | - M S Ramirez
- Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA, USA
| | - F Götz
- Department of Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | - P M Tribelli
- Instituto De Química Biológica de La Facultad de Ciencias Exactas y Naturales-CONICET, Buenos Aires, Argentina.
- Departamento de Química Biológica, FCEyN-UBA, Buenos Aires, Argentina.
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7
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Solar Venero EC, Galeano MB, Luqman A, Ricardi MM, Serral F, Fernandez Do Porto D, Robaldi SA, Ashari B, Munif TH, Egoburo DE, Nemirovsky S, Escalante J, Nishimura B, Ramirez MS, Götz F, Tribelli PM. Fever-like temperature impacts on Staphylococcus aureus and Pseudomonas aeruginosa interaction, physiology, and virulence both in vitro and in vivo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.21.529514. [PMID: 36993402 PMCID: PMC10055263 DOI: 10.1101/2023.03.21.529514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Background Staphylococcus aureus and Pseudomonas aeruginosa cause a wide variety of bacterial infections and coinfections, showing a complex interaction that involves the production of different metabolites and metabolic changes. Temperature is a key factor for bacterial survival and virulence and within the host, bacteria could be exposed to an increment in temperature during fever development. We analyzed the previously unexplored effect of fever-like temperatures (39°C) on S. aureus USA300 and P. aeruginosa PAO1 microaerobic mono- and co-cultures compared with 37°C, by using RNAseq and physiological assays including in-vivo experiments. Results In general terms both temperature and co-culturing had a strong impact on both PA and SA with the exception of the temperature response of monocultured PA. We studied metabolic and virulence changes on both species. Altered metabolic features at 39°C included arginine biosynthesis and the periplasmic glucose oxidation in S. aureus and P. aeruginosa monocultures respectively. When PA co-cultures were exposed at 39°C they upregulated ethanol oxidation related genes along with an increment in organic acid accumulation. Regarding virulence factors, monocultured SA showed an increase in the mRNA expression of the agr operon and hld, pmsα and pmsβ genes at 39°C. Supported by mRNA data, we performed physiological experiments and detected and increment in hemolysis, staphylxantin production and a decrease in biofilm formation at 39°C. On the side of PA monocultures, we observed increase in extracellular lipase and protease and biofilm formation at 39°C along with a decrease in motility in correlation with changes observed at mRNA abundance. Additionally, we assessed host-pathogen interaction both in-vitro and in-vivo . S. aureus monocultured at 39°C showed a decrease in cellular invasion and an increase in IL-8 -but not in IL-6- production by A549 cell line. PA also decreased its cellular invasion when monocultured at 39°C and did not induce any change in IL-8 or IL-6 production. PA strongly increased cellular invasion when co-cultured at 37°C and 39°C. Finally, we observed increased lethality in mice intranasally inoculated with S. aureus monocultures pre-incubated at 39°C and even higher levels when inoculated with co-cultures. The bacterial burden for P. aeruginosa was higher in liver when the mice were infected with co-cultures previously incubated at 39°C comparing with 37°C. Conclusion Our results highlight a relevant change in the virulence of bacterial opportunistic pathogens exposed to fever-like temperatures in presence of competitors, opening new questions related to bacteria-bacteria and host-pathogen interactions and coevolution.
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Tribelli PM, López NI. Insights into the temperature responses of Pseudomonas species in beneficial and pathogenic host interactions. Appl Microbiol Biotechnol 2022; 106:7699-7709. [PMID: 36271255 DOI: 10.1007/s00253-022-12243-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 09/30/2022] [Accepted: 10/12/2022] [Indexed: 11/28/2022]
Abstract
Pseudomonas species are metabolically versatile bacteria able to exploit a wide range of ecological niches. Different Pseudomonas species can grow as free-living cells, biofilms, or associated with plants or animals, including humans, and their ecological success partially lies in their ability to grow and adapt to different temperatures. These bacteria are relevant for human activities, due to their clinical importance and their biotechnological potential for different applications such as bioremediation and the production of biopolymers, surfactants, secondary metabolites, and enzymes. In agriculture, some of them can act as plant growth promoters and are thus used as inoculants, whereas others, like P. syringae pathovars, can cause disease in commercial crops. This review aims to provide an overview of the temperature-response mechanisms in Pseudomonas species, looking for novel features or strategies based on techniques such as transcriptomics and proteomics. We focused on temperature-dependent traits mainly associated with virulence, host colonization, survival, and production of secondary metabolites. We analyzed human, animal, and plant pathogens and plant growth-promoting Pseudomonas species, including P. aeruginosa, P. plecoglossicida, several P. syringae pathovars, and P. protegens. Our aim was to provide a comprehensive view of the relevance of temperature-response traits in human and animal health and agricultural applications. Our analysis showed that features relevant to the bacterial-host interaction are adjusted to the environmental or host temperature regardless of the optimal growth temperature in the laboratory, and thus contribute to improving bacterial fitness. KEY POINTS: • In Pseudomonas species, temperature impacts the bacterial-host interaction. • Interaction traits are expressed at temperatures different from the optimal reported. • The bacterial-host interaction could be affected by climate change.
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Affiliation(s)
- Paula M Tribelli
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, 1428EGA, Buenos Aires, Argentina. .,IQUIBICEN-CONICET, Buenos Aires, Argentina.
| | - Nancy I López
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, 1428EGA, Buenos Aires, Argentina.,IQUIBICEN-CONICET, Buenos Aires, Argentina
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Nutrient Sensing and Biofilm Modulation: The Example of L-arginine in Pseudomonas. Int J Mol Sci 2022; 23:ijms23084386. [PMID: 35457206 PMCID: PMC9028604 DOI: 10.3390/ijms23084386] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 04/12/2022] [Accepted: 04/13/2022] [Indexed: 12/01/2022] Open
Abstract
Bacterial biofilm represents a multicellular community embedded within an extracellular matrix attached to a surface. This lifestyle confers to bacterial cells protection against hostile environments, such as antibiotic treatment and host immune response in case of infections. The Pseudomonas genus is characterised by species producing strong biofilms difficult to be eradicated and by an extraordinary metabolic versatility which may support energy and carbon/nitrogen assimilation under multiple environmental conditions. Nutrient availability can be perceived by a Pseudomonas biofilm which, in turn, readapts its metabolism to finally tune its own formation and dispersion. A growing number of papers is now focusing on the mechanism of nutrient perception as a possible strategy to weaken the biofilm barrier by environmental cues. One of the most important nutrients is amino acid L-arginine, a crucial metabolite sustaining bacterial growth both as a carbon and a nitrogen source. Under low-oxygen conditions, L-arginine may also serve for ATP production, thus allowing bacteria to survive in anaerobic environments. L-arginine has been associated with biofilms, virulence, and antibiotic resistance. L-arginine is also a key precursor of regulatory molecules such as polyamines, whose involvement in biofilm homeostasis is reported. Given the biomedical and biotechnological relevance of biofilm control, the state of the art on the effects mediated by the L-arginine nutrient on biofilm modulation is presented, with a special focus on the Pseudomonas biofilm. Possible biotechnological and biomedical applications are also discussed.
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Brinkman FSL, Winsor GL, Done RE, Filloux A, Francis VI, Goldberg JB, Greenberg EP, Han K, Hancock REW, Haney CH, Häußler S, Klockgether J, Lamont IL, Levesque RC, Lory S, Nikel PI, Porter SL, Scurlock MW, Schweizer HP, Tümmler B, Wang M, Welch M. The Pseudomonas aeruginosa whole genome sequence: A 20th anniversary celebration. Adv Microb Physiol 2021; 79:25-88. [PMID: 34836612 DOI: 10.1016/bs.ampbs.2021.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Toward the end of August 2000, the 6.3 Mbp whole genome sequence of Pseudomonas aeruginosa strain PAO1 was published. With 5570 open reading frames (ORFs), PAO1 had the largest microbial genome sequenced up to that point in time-including a large proportion of metabolic, transport and antimicrobial resistance genes supporting its ability to colonize diverse environments. A remarkable 9% of its ORFs were predicted to encode proteins with regulatory functions, providing new insight into bacterial network complexity as a function of network size. In this celebratory article, we fast forward 20 years, and examine how access to this resource has transformed our understanding of P. aeruginosa. What follows is more than a simple review or commentary; we have specifically asked some of the leaders in the field to provide personal reflections on how the PAO1 genome sequence, along with the Pseudomonas Community Annotation Project (PseudoCAP) and Pseudomonas Genome Database (pseudomonas.com), have contributed to the many exciting discoveries in this field. In addition to bringing us all up to date with the latest developments, we also ask our contributors to speculate on how the next 20 years of Pseudomonas research might pan out.
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Affiliation(s)
- Fiona S L Brinkman
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Geoffrey L Winsor
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Rachel E Done
- Department of Pediatrics, Division of Pulmonary, Allergy and Immunology, Cystic Fibrosis, and Sleep, Emory Children's Center for Cystic Fibrosis and Airway Disease Research, Emory University School of Medicine, Atlanta, GA, United States
| | - Alain Filloux
- Department of Life Sciences, MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Vanessa I Francis
- Geoffrey Pope Building, University of Exeter, Exeter, United Kingdom
| | - Joanna B Goldberg
- Department of Pediatrics, Division of Pulmonary, Allergy and Immunology, Cystic Fibrosis, and Sleep, Emory Children's Center for Cystic Fibrosis and Airway Disease Research, Emory University School of Medicine, Atlanta, GA, United States
| | - E Peter Greenberg
- Department of Microbiology, University of Washington, Seattle, WA, United States
| | - Kook Han
- Department of Microbiology, Harvard Medical School, Boston, MA, United States
| | | | - Cara H Haney
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, BC, Canada
| | - Susanne Häußler
- Department of Molecular Bacteriology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Jens Klockgether
- Klinik für Pädiatrische Pneumologie, Allergologie und Neonatologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Iain L Lamont
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
| | - Roger C Levesque
- Institut de biologie intégrative et des systèmes (IBIS), Pavillon Charles-Eugène Marchand, Faculté of Médicine, Université Laval, Québec City, QC, Canada
| | - Stephen Lory
- Department of Microbiology, Harvard Medical School, Boston, MA, United States
| | - Pablo I Nikel
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Steven L Porter
- Geoffrey Pope Building, University of Exeter, Exeter, United Kingdom
| | | | - Herbert P Schweizer
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
| | - Burkhard Tümmler
- Klinik für Pädiatrische Pneumologie, Allergologie und Neonatologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Meng Wang
- Department of Biochemistry (Hopkins Building), University of Cambridge, Cambridge, United Kingdom
| | - Martin Welch
- Department of Biochemistry (Hopkins Building), University of Cambridge, Cambridge, United Kingdom.
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11
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Abou Saleh L, Boyd A, Aragon IV, Koloteva A, Spadafora D, Mneimneh W, Barrington RA, Richter W. Ablation of PDE4B protects from Pseudomonas aeruginosa-induced acute lung injury in mice by ameliorating the cytostorm and associated hypothermia. FASEB J 2021; 35:e21797. [PMID: 34383981 DOI: 10.1096/fj.202100495r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 06/24/2021] [Accepted: 06/29/2021] [Indexed: 12/16/2022]
Abstract
Pseudomonas aeruginosa is a frequent cause of hospital-acquired lung infections characterized by hyperinflammation, antibiotic resistance, and high morbidity/mortality. Here, we show that the genetic ablation of one cAMP-phosphodiesterase 4 subtype, PDE4B, is sufficient to protect mice from acute lung injury induced by P aeruginosa infection as it reduces pulmonary and systemic levels of pro-inflammatory cytokines, as well as pulmonary vascular leakage and mortality. Surprisingly, despite dampening immune responses, bacterial clearance in the lungs of PDE4B-KO mice is significantly improved compared to WT controls. In wildtypes, P aeruginosa-infection produces high systemic levels of several cytokines, including TNF-α, IL-1β, and IL-6, that act as cryogens and render the animals hypothermic. This, in turn, diminishes their ability to clear the bacteria. Ablation of PDE4B curbs both the initial production of acute response cytokines, including TNF-α and IL-1β, as well as their downstream signaling, specifically the induction of the secondary-response cytokine IL-6. This synergistic action protects PDE4B-KO mice from the deleterious effects of the P aeruginosa-induced cytostorm, while concurrently improving bacterial clearance, rather than being immunosuppressive. These benefits of PDE4B ablation are in contrast to the effects resulting from treatment with PAN-PDE4 inhibitors, which have been shown to increase bacterial burden and dissemination. Thus, PDE4B represents a promising therapeutic target in settings of P aeruginosa lung infections.
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Affiliation(s)
- Lina Abou Saleh
- Department of Biochemistry & Molecular Biology, College of Medicine, University of South Alabama, Mobile, AL, USA.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, USA
| | - Abigail Boyd
- Department of Biochemistry & Molecular Biology, College of Medicine, University of South Alabama, Mobile, AL, USA.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, USA
| | - Ileana V Aragon
- Department of Biochemistry & Molecular Biology, College of Medicine, University of South Alabama, Mobile, AL, USA.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, USA
| | - Anna Koloteva
- Department of Biochemistry & Molecular Biology, College of Medicine, University of South Alabama, Mobile, AL, USA.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, USA
| | - Domenico Spadafora
- Department of Microbiology & Immunology, College of Medicine, University of South Alabama, Mobile, AL, USA
| | - Wadad Mneimneh
- Department of Pathology, College of Medicine, University of South Alabama, Mobile, AL, USA
| | - Robert A Barrington
- Department of Microbiology & Immunology, College of Medicine, University of South Alabama, Mobile, AL, USA
| | - Wito Richter
- Department of Biochemistry & Molecular Biology, College of Medicine, University of South Alabama, Mobile, AL, USA.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, USA
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12
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Bisht K, Moore JL, Caprioli RM, Skaar EP, Wakeman CA. Impact of temperature-dependent phage expression on Pseudomonas aeruginosa biofilm formation. NPJ Biofilms Microbiomes 2021; 7:22. [PMID: 33727555 PMCID: PMC7966754 DOI: 10.1038/s41522-021-00194-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 02/05/2021] [Indexed: 01/31/2023] Open
Abstract
Pseudomonas aeruginosa is a ubiquitous opportunistic pathogen that forms robust biofilms in the different niches it occupies. Numerous physiological adaptations are required as this organism shifts from soil or aquatic environments to a host-associated lifestyle. While many conditions differ between these niches, temperature shifts are a factor that can contribute to physiological stress during this transition. To understand how temperature impacts biofilm formation in this pathogen, we used proteomic and transcriptomic tools to elucidate physiological responses in environment-relevant vs. host-relevant temperatures. These studies uncovered differential expression of various proteins including a phage protein that is associated with the EPS matrix in P. aeruginosa. This filamentous phage was induced at host temperatures and was required for full biofilm-forming capacity specifically at human body temperature. These data highlight the importance of temperature shift in biofilm formation and suggest bacteriophage proteins could be a possible therapeutic target in biofilm-associated infections.
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Affiliation(s)
- Karishma Bisht
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA
| | - Jessica L Moore
- Department of Chemistry, Vanderbilt University, Nashville, TN, USA
| | | | - Eric P Skaar
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
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13
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Saati-Santamaría Z, Rivas R, Kolařik M, García-Fraile P. A New Perspective of Pseudomonas-Host Interactions: Distribution and Potential Ecological Functions of the Genus Pseudomonas within the Bark Beetle Holobiont. BIOLOGY 2021; 10:biology10020164. [PMID: 33669823 PMCID: PMC7922261 DOI: 10.3390/biology10020164] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 02/14/2021] [Accepted: 02/16/2021] [Indexed: 12/17/2022]
Abstract
Symbiosis between microbes and insects has been raised as a promising area for understanding biological implications of microbe-host interactions. Among them, the association between fungi and bark beetles has been generally recognized as essential for the bark beetle ecology. However, many works investigating bark beetle bacterial communities and their functions usually meet in a common finding: Pseudomonas is a broadly represented genus within this holobiont and it may provide beneficial roles to its host. Thus, we aimed to review available research on this microbe-host interaction and point out the probable relevance of Pseudomonas strains for these insects, in order to guide future research toward a deeper analysis of the importance of these bacteria for the beetle's life cycle.
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Affiliation(s)
- Zaki Saati-Santamaría
- Microbiology and Genetics Department, University of Salamanca, 37007 Salamanca, Spain;
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Villamayor, 37185 Salamanca, Spain
- Correspondence: (Z.S.-S.); (P.G.-F.)
| | - Raúl Rivas
- Microbiology and Genetics Department, University of Salamanca, 37007 Salamanca, Spain;
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Villamayor, 37185 Salamanca, Spain
- Associated Research Unit of Plant-Microorganism Interaction, USAL-CSIC (IRNASA), 37008 Salamanca, Spain
| | - Miroslav Kolařik
- Department of Botany, Faculty of Science, Charles University, 128 01 Prague, Czech Republic;
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic
| | - Paula García-Fraile
- Microbiology and Genetics Department, University of Salamanca, 37007 Salamanca, Spain;
- Spanish-Portuguese Institute for Agricultural Research (CIALE), Villamayor, 37185 Salamanca, Spain
- Associated Research Unit of Plant-Microorganism Interaction, USAL-CSIC (IRNASA), 37008 Salamanca, Spain
- Correspondence: (Z.S.-S.); (P.G.-F.)
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14
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Lee AJ, Park Y, Doing G, Hogan DA, Greene CS. Correcting for experiment-specific variability in expression compendia can remove underlying signals. Gigascience 2020; 9:giaa117. [PMID: 33140829 PMCID: PMC7607552 DOI: 10.1093/gigascience/giaa117] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 08/28/2020] [Accepted: 09/29/2020] [Indexed: 11/14/2022] Open
Abstract
MOTIVATION In the past two decades, scientists in different laboratories have assayed gene expression from millions of samples. These experiments can be combined into compendia and analyzed collectively to extract novel biological patterns. Technical variability, or "batch effects," may result from combining samples collected and processed at different times and in different settings. Such variability may distort our ability to extract true underlying biological patterns. As more integrative analysis methods arise and data collections get bigger, we must determine how technical variability affects our ability to detect desired patterns when many experiments are combined. OBJECTIVE We sought to determine the extent to which an underlying signal was masked by technical variability by simulating compendia comprising data aggregated across multiple experiments. METHOD We developed a generative multi-layer neural network to simulate compendia of gene expression experiments from large-scale microbial and human datasets. We compared simulated compendia before and after introducing varying numbers of sources of undesired variability. RESULTS The signal from a baseline compendium was obscured when the number of added sources of variability was small. Applying statistical correction methods rescued the underlying signal in these cases. However, as the number of sources of variability increased, it became easier to detect the original signal even without correction. In fact, statistical correction reduced our power to detect the underlying signal. CONCLUSION When combining a modest number of experiments, it is best to correct for experiment-specific noise. However, when many experiments are combined, statistical correction reduces our ability to extract underlying patterns.
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Affiliation(s)
- Alexandra J Lee
- Genomics and Computational Biology Graduate Program, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA
- Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA
| | - YoSon Park
- Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA
| | - Georgia Doing
- Department of Microbiology and Immunology, Geisel School of Medicine, Dartmouth, 1 Rope Ferry Rd, Hanover, NH, 03755, USA
| | - Deborah A Hogan
- Department of Microbiology and Immunology, Geisel School of Medicine, Dartmouth, 1 Rope Ferry Rd, Hanover, NH, 03755, USA
| | - Casey S Greene
- Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA
- Childhood Cancer Data Lab, Alex's Lemonade Stand Foundation, 1429 Walnut St, Floor 10, Philadelphia, PA, 19102 USA
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15
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Sauvage S, Hardouin J. Exoproteomics for Better Understanding Pseudomonas aeruginosa Virulence. Toxins (Basel) 2020; 12:E571. [PMID: 32899849 PMCID: PMC7551764 DOI: 10.3390/toxins12090571] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 08/25/2020] [Accepted: 09/01/2020] [Indexed: 12/12/2022] Open
Abstract
Pseudomonas aeruginosa is the most common human opportunistic pathogen associated with nosocomial diseases. In 2017, the World Health Organization has classified P. aeruginosa as a critical agent threatening human health, and for which the development of new treatments is urgently necessary. One interesting avenue is to target virulence factors to understand P. aeruginosa pathogenicity. Thus, characterising exoproteins of P. aeruginosa is a hot research topic and proteomics is a powerful approach that provides important information to gain insights on bacterial virulence. The aim of this review is to focus on the contribution of proteomics to the studies of P. aeruginosa exoproteins, highlighting its relevance in the discovery of virulence factors, post-translational modifications on exoproteins and host-pathogen relationships.
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Affiliation(s)
- Salomé Sauvage
- Polymers, Biopolymers, Surface Laboratory, UMR 6270 CNRS, University of Rouen, CEDEX, F-76821 Mont-Saint-Aignan, France;
- PISSARO Proteomics Facility, IRIB, F-76820 Mont-Saint-Aignan, France
| | - Julie Hardouin
- Polymers, Biopolymers, Surface Laboratory, UMR 6270 CNRS, University of Rouen, CEDEX, F-76821 Mont-Saint-Aignan, France;
- PISSARO Proteomics Facility, IRIB, F-76820 Mont-Saint-Aignan, France
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16
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Rinaldo S, Giardina G, Mantoni F, Paone A, Cutruzzolà F. Beyond nitrogen metabolism: nitric oxide, cyclic-di-GMP and bacterial biofilms. FEMS Microbiol Lett 2019; 365:4834012. [PMID: 29401255 DOI: 10.1093/femsle/fny029] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 01/31/2018] [Indexed: 12/18/2022] Open
Abstract
The nitrogen cycle pathways are responsible for the circulation of inorganic and organic N-containing molecules in nature. Among these pathways, those involving amino acids, N-oxides and in particular nitric oxide (NO) play strategic roles in the metabolism of microorganisms in natural environments and in host-pathogen interactions. Beyond their role in the N-cycle, amino acids and NO are also signalling molecules able to influence group behaviour in microorganisms and cell-cell communication in multicellular organisms, including humans. In this minireview, we summarise the role of these compounds in the homeostasis of the bacterial communities called biofilms, commonly found in environmental, industrial and medical settings. Biofilms are difficult to eradicate since they are highly resistant to antimicrobials and to the host immune system. We highlight the effect of amino acids such as glutamate, glutamine and arginine and of NO on the signalling pathways involved in the metabolism of 3',5'-cyclic diguanylic acid (c-di-GMP), a master regulator of motility, attachment and group behaviour in bacteria. The study of the metabolic routes involving these N-containing compounds represents an attractive topic to identify targets for biofilm control in both natural and medical settings.
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Affiliation(s)
- Serena Rinaldo
- Department of Biochemical Sciences, Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, 00185 Rome, Italy
| | - Giorgio Giardina
- Department of Biochemical Sciences, Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, 00185 Rome, Italy
| | - Federico Mantoni
- Department of Biochemical Sciences, Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, 00185 Rome, Italy
| | - Alessio Paone
- Department of Biochemical Sciences, Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, 00185 Rome, Italy
| | - Francesca Cutruzzolà
- Department of Biochemical Sciences, Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University of Rome, 00185 Rome, Italy
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17
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Kumar SS, Penesyan A, Elbourne LDH, Gillings MR, Paulsen IT. Catabolism of Nucleic Acids by a Cystic Fibrosis Pseudomonas aeruginosa Isolate: An Adaptive Pathway to Cystic Fibrosis Sputum Environment. Front Microbiol 2019; 10:1199. [PMID: 31214142 PMCID: PMC6555301 DOI: 10.3389/fmicb.2019.01199] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 05/13/2019] [Indexed: 11/13/2022] Open
Abstract
Pseudomonas aeruginosa is a major cause of morbidity and mortality in patients with cystic fibrosis (CF). We undertook Biolog Phenotype Microarray testing of P. aeruginosa CF isolates to investigate their catabolic capabilities compared to P. aeruginosa laboratory strains PAO1 and PA14. One strain, PASS4, displayed an unusual phenotype, only showing strong respiration on adenosine and inosine. Further testing indicated that PASS4 could grow on DNA as a sole carbon source, with a higher biomass production than PAO1. This suggested that PASS4 was specifically adapted to metabolize extracellular DNA, a substrate present at high concentrations in the CF lung. Transcriptomic and proteomic profiling of PASS4 and PAO1 when grown with DNA as a sole carbon source identified a set of upregulated genes, including virulence and host-adaptation genes. PASS4 was unable to utilize N-Acetyl-D-glucosamine, and when we selected PASS4 mutants able to grow on this carbon source, they also displayed a gain in ability to catabolize a broad range of other carbon sources. Genome sequencing of the mutants revealed they all contained mutations within the purK gene, encoding a key protein in the de novo purine biosynthesis pathway. This suggested that PASS4 was a purine auxotroph. Growth assays in the presence of 2 mM adenosine and the complementation of PASS4 with an intact purK gene confirmed this conclusion. Purine auxotrophy may represent a viable microbial strategy for adaptation to DNA-rich environments such as the CF lung.
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Affiliation(s)
| | - Anahit Penesyan
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
| | | | - Michael R Gillings
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - Ian T Paulsen
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
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18
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Rudenko I, Ni B, Glatter T, Sourjik V. Inefficient Secretion of Anti-sigma Factor FlgM Inhibits Bacterial Motility at High Temperature. iScience 2019; 16:145-154. [PMID: 31170626 PMCID: PMC6551532 DOI: 10.1016/j.isci.2019.05.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 04/01/2019] [Accepted: 05/15/2019] [Indexed: 12/03/2022] Open
Abstract
Temperature is one of the key cues that enable microorganisms to adjust their physiology in response to environmental changes. Here we show that motility is the major cellular function of Escherichia coli that is differentially regulated between growth at normal host temperature of 37°C and the febrile temperature of 42°C. Expression of both class II and class III flagellar genes is reduced at 42°C because of lowered level of the upstream activator FlhD. Class III genes are additionally repressed because of the destabilization and malfunction of secretion apparatus at high temperature, which prevents secretion of the anti-sigma factor FlgM. This mechanism of repression apparently accelerates loss of motility at 42°C. We hypothesize that E. coli perceives high temperature as a sign of inflammation, downregulating flagella to escape detection by the immune system of the host. Secretion-dependent coupling of gene expression to the environmental temperature is likely common among many bacteria. E. coli motility is tightly turned off at febrile temperature (42°C) Repression of motility is achieved at two levels of hierarchical gene regulation Lowered FlhD level reduces expression of all flagellar genes Impaired FlgM secretion tightens repression of class III genes
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Affiliation(s)
- Iaroslav Rudenko
- Department of Systems and Synthetic Microbiology, Max Planck Institute for Terrestrial Microbiology & LOEWE Center for Synthetic Microbiology (SYNMIKRO), Marburg 35043, Germany
| | - Bin Ni
- Department of Systems and Synthetic Microbiology, Max Planck Institute for Terrestrial Microbiology & LOEWE Center for Synthetic Microbiology (SYNMIKRO), Marburg 35043, Germany
| | - Timo Glatter
- Core Facility for Mass Spectrometry & Proteomics, Max Planck Institute for Terrestrial Microbiology, Marburg 35043, Germany
| | - Victor Sourjik
- Department of Systems and Synthetic Microbiology, Max Planck Institute for Terrestrial Microbiology & LOEWE Center for Synthetic Microbiology (SYNMIKRO), Marburg 35043, Germany.
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Abstract
In vitro growth conditions for bacteria do not fully recapitulate the host environment. RNA sequencing transcriptome analysis allows for the characterization of the infection gene expression profiles of pathogens in complex environments. Isolation of the pathogen from infected tissues is critical because of the large amounts of host RNA present in crude lysates of infected organs. A filtration method was developed that enabled enrichment of the pathogen RNA for RNA-seq analysis. The resulting data describe the “infection transcriptome” of B. pertussis in the murine lung. This strategy can be utilized for pathogens in other hosts and, thus, expand our knowledge of what bacteria express during infection. Bordetella pertussis causes the disease whooping cough through coordinated control of virulence factors by the Bordetella virulence gene system. Microarrays and, more recently, RNA sequencing (RNA-seq) have been used to describe in vitro gene expression profiles of B. pertussis and other pathogens. In previous studies, we have analyzed the in vitro gene expression profiles of B. pertussis, and we hypothesize that the infection transcriptome profile in vivo is significantly different from that under laboratory growth conditions. To study the infection transcriptome of B. pertussis, we developed a simple filtration technique for isolation of bacteria from infected lungs. The work flow involves filtering the bacteria out of the lung homogenate using a 5-μm-pore-size syringe filter. The captured bacteria are then lysed to isolate RNA for Illumina library preparation and RNA-seq analysis. Upon comparing the in vitro and in vivo gene expression profiles, we identified 351 and 255 genes as activated and repressed, respectively, during murine lung infection. As expected, numerous genes associated with virulent-phase growth were activated in the murine host, including pertussis toxin (PT), the PT secretion apparatus, and the type III secretion system. A significant number of genes encoding iron acquisition and heme uptake proteins were highly expressed during infection, supporting iron acquisition as critical for B. pertussis survival in vivo. Numerous metabolic genes were repressed during infection. Overall, these data shed light on the gene expression profile of B. pertussis during infection, and this method will facilitate efforts to understand how this pathogen causes infection. IMPORTANCEIn vitro growth conditions for bacteria do not fully recapitulate the host environment. RNA sequencing transcriptome analysis allows for the characterization of the infection gene expression profiles of pathogens in complex environments. Isolation of the pathogen from infected tissues is critical because of the large amounts of host RNA present in crude lysates of infected organs. A filtration method was developed that enabled enrichment of the pathogen RNA for RNA-seq analysis. The resulting data describe the “infection transcriptome” of B. pertussis in the murine lung. This strategy can be utilized for pathogens in other hosts and, thus, expand our knowledge of what bacteria express during infection.
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20
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Prezioso SM, Duong DM, Kuiper EG, Deng Q, Albertí S, Conn GL, Goldberg JB. Trimethylation of Elongation Factor-Tu by the Dual Thermoregulated Methyltransferase EftM Does Not Impact Its Canonical Function in Translation. Sci Rep 2019; 9:3553. [PMID: 30837495 PMCID: PMC6401129 DOI: 10.1038/s41598-019-39331-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 01/23/2019] [Indexed: 11/28/2022] Open
Abstract
The Pseudomonas aeruginosa methyltransferase EftM trimethylates elongation factor-Tu (EF-Tu) on lysine 5 to form a post-translational modification important for initial bacterial adherence to host epithelial cells. EftM methyltransferase activity is directly temperature regulated. The protein stability of EftM is tuned with a melting temperature (Tm) around 37 °C such that the enzyme is stable and active at 25 °C, but is completely inactivated by protein unfolding at higher temperatures. This leads to higher observable levels of EF-Tu trimethylation at the lower temperature. Here we report an additional layer of thermoregulation resulting in lower eftM mRNA transcript level at 37 °C compared to 25 °C and show that this regulation occurs at the level of transcription initiation. To begin to define the impact of this system on P. aeruginosa physiology, we demonstrate that EF-Tu is the only observable substrate for EftM. Further, we interrogated the proteome of three different wild-type P. aeruginosa strains, their eftM mutants, and these mutants complemented with eftM and conclude that trimethylation of EF-Tu by EftM does not impact EF-Tu’s canonical function in translation. In addition to furthering our knowledge of this Pseudomonas virulence factor, this study provides an intriguing example of a protein with multiple layers of thermoregulation.
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Affiliation(s)
- Samantha M Prezioso
- Microbiology and Molecular Genetics (MMG) Program, Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, GA, 30322, USA.,Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Duc M Duong
- Emory Integrated Proteomics Core, Emory University, Atlanta, GA, 30322, USA
| | - Emily G Kuiper
- Biochemistry, Cell and Developmental Biology (BCDB) Program, Graduate Division of Biological and Biomedical Sciences, Emory University, Atlanta, GA, 30322, USA.,Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Qiudong Deng
- Emory Integrated Proteomics Core, Emory University, Atlanta, GA, 30322, USA
| | - Sebastián Albertí
- Instituto Universitario de Investigación en Ciencias de la Salud, Universidad de las Islas Baleares, Palma de Mallorca, Spain
| | - Graeme L Conn
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA.,Emory Antibiotic Resistance Center, Atlanta, GA, 30322, USA
| | - Joanna B Goldberg
- Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA. .,Emory Antibiotic Resistance Center, Atlanta, GA, 30322, USA. .,Emory + Children's Center for Cystic Fibrosis and Airway Disease Research, Atlanta, GA, 30322, USA.
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Jatsenko T, Sidorenko J, Saumaa S, Kivisaar M. DNA Polymerases ImuC and DinB Are Involved in DNA Alkylation Damage Tolerance in Pseudomonas aeruginosa and Pseudomonas putida. PLoS One 2017; 12:e0170719. [PMID: 28118378 PMCID: PMC5261740 DOI: 10.1371/journal.pone.0170719] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 01/09/2017] [Indexed: 12/12/2022] Open
Abstract
Translesion DNA synthesis (TLS), facilitated by low-fidelity polymerases, is an important DNA damage tolerance mechanism. Here, we investigated the role and biological function of TLS polymerase ImuC (former DnaE2), generally present in bacteria lacking DNA polymerase V, and TLS polymerase DinB in response to DNA alkylation damage in Pseudomonas aeruginosa and P. putida. We found that TLS DNA polymerases ImuC and DinB ensured a protective role against N- and O-methylation induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in both P. aeruginosa and P. putida. DinB also appeared to be important for the survival of P. aeruginosa and rapidly growing P. putida cells in the presence of methyl methanesulfonate (MMS). The role of ImuC in protection against MMS-induced damage was uncovered under DinB-deficient conditions. Apart from this, both ImuC and DinB were critical for the survival of bacteria with impaired base excision repair (BER) functions upon alkylation damage, lacking DNA glycosylases AlkA and/or Tag. Here, the increased sensitivity of imuCdinB double deficient strains in comparison to single mutants suggested that the specificity of alkylated DNA lesion bypass of DinB and ImuC might also be different. Moreover, our results demonstrated that mutagenesis induced by MMS in pseudomonads was largely ImuC-dependent. Unexpectedly, we discovered that the growth temperature of bacteria affected the efficiency of DinB and ImuC in ensuring cell survival upon alkylation damage. Taken together, the results of our study disclosed the involvement of ImuC in DNA alkylation damage tolerance, especially at low temperatures, and its possible contribution to the adaptation of pseudomonads upon DNA alkylation damage via increased mutagenesis.
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Affiliation(s)
- Tatjana Jatsenko
- Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
- * E-mail: (MK); (TJ)
| | - Julia Sidorenko
- Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
| | - Signe Saumaa
- Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
| | - Maia Kivisaar
- Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
- * E-mail: (MK); (TJ)
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22
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Dual-seq transcriptomics reveals the battle for iron during Pseudomonas aeruginosa acute murine pneumonia. Sci Rep 2016; 6:39172. [PMID: 27982111 PMCID: PMC5159919 DOI: 10.1038/srep39172] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 11/18/2016] [Indexed: 12/21/2022] Open
Abstract
Determining bacterial gene expression during infection is fundamental to understand pathogenesis. In this study, we used dual RNA-seq to simultaneously measure P. aeruginosa and the murine host’s gene expression and response to respiratory infection. Bacterial genes encoding products involved in metabolism and virulence were differentially expressed during infection and the type III and VI secretion systems were highly expressed in vivo. Strikingly, heme acquisition, ferric-enterobactin transport, and pyoverdine biosynthesis genes were found to be significantly up-regulated during infection. In the mouse, we profiled the acute immune response to P. aeruginosa and identified the pro-inflammatory cytokines involved in acute response to the bacterium in the lung. Additionally, we also identified numerous host iron sequestration systems upregulated during infection. Overall, this work sheds light on how P. aeruginosa triggers a pro-inflammatory response and competes for iron with the host during infection, as iron is one of the central elements for which both pathogen and host fight during acute pneumonia.
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23
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Yu H, Xiong J, Zhang R, Hu X, Qiu J, Zhang D, Xu X, Xin R, He X, Xie W, Sheng H, Chen Q, Zhang L, Rao X, Zhang K. Ndk, a novel host-responsive regulator, negatively regulates bacterial virulence through quorum sensing in Pseudomonas aeruginosa. Sci Rep 2016; 6:28684. [PMID: 27345215 PMCID: PMC4921839 DOI: 10.1038/srep28684] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 06/08/2016] [Indexed: 11/09/2022] Open
Abstract
Pathogenic bacteria could adjust gene expression to enable their survival in the distinct host environment. However, the mechanism by which bacteria adapt to the host environment is not well described. In this study, we demonstrated that nucleoside diphosphate kinase (Ndk) of Pseudomonas aeruginosa is critical for adjusting the bacterial virulence determinants during infection. Ndk expression was down-regulated in the pulmonary alveoli of a mouse model of acute pneumonia. Knockout of ndk up-regulated transcription factor ExsA-mediated T3S regulon expression and decreased exoproduct-related gene expression through the inhibition of the quorum sensing hierarchy. Moreover, in vitro and in vivo studies demonstrated that the ndk mutant exhibits enhanced cytotoxicity and host pathogenicity by increasing T3SS proteins. Taken together, our data reveal that ndk is a critical novel host-responsive gene required for coordinating P. aeruginosa virulence upon acute infection.
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Affiliation(s)
- Hua Yu
- Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University, Chongqing, China.,Central Laboratory, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Junzhi Xiong
- Central Laboratory, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Rong Zhang
- Department of Pharmacy, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Xiaomei Hu
- Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University, Chongqing, China
| | - Jing Qiu
- Central Laboratory, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Di Zhang
- Central Laboratory, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Xiaohui Xu
- Central Laboratory, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Rong Xin
- Central Laboratory, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Xiaomei He
- Central Laboratory, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Wei Xie
- Central Laboratory, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Halei Sheng
- Central Laboratory, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Qian Chen
- Central Laboratory, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Le Zhang
- Central Laboratory, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Xiancai Rao
- Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University, Chongqing, China
| | - Kebin Zhang
- Central Laboratory, Xinqiao Hospital, Third Military Medical University, Chongqing, China
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24
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A Tale of Transmission: Aeromonas veronii Activity within Leech-Exuded Mucus. Appl Environ Microbiol 2016; 82:2644-55. [PMID: 26896136 DOI: 10.1128/aem.00185-16] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 02/16/2016] [Indexed: 11/20/2022] Open
Abstract
Transmission, critical to the establishment and persistence of host-associated microbiotas, also exposes symbionts to new environmental conditions. With horizontal transmission, these different conditions represent major lifestyle shifts. Yet genome-wide analyses of how microbes adjust their transcriptomes toward these dramatic shifts remain understudied. Here, we provide a comprehensive and comparative analysis of the global transcriptional profiles of a symbiont as it shifts between lifestyles during transmission. The gammaproteobacterium Aeromonas veronii is transmitted from the gut of the medicinal leech to other hosts via host mucosal castings, yet A. veronii can also transition from mucosal habitancy to a free-living lifestyle. These three lifestyles are characterized by distinct physiological constraints and consequently lifestyle-specific changes in the expression of stress-response genes. Mucus-bound A. veronii had the greatest expression in terms of both the number of loci and levels of transcription of stress-response mechanisms. However, these bacteria are still capable of proliferating within the mucus, suggesting the availability of nutrients within this environment. We found that A. veronii alters transcription of loci in a synthetic pathway that obtains and incorporates N-acetylglucosamine (NAG; a major component of mucus) into the bacterial cell wall, enabling proliferation. Our results demonstrate that symbionts undergo dramatic local adaptation, demonstrated by widespread transcriptional changes, throughout the process of transmission that allows them to thrive while they encounter new environments which further shape their ecology and evolution.
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25
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Owings JP, Kuiper EG, Prezioso SM, Meisner J, Varga JJ, Zelinskaya N, Dammer EB, Duong DM, Seyfried NT, Albertí S, Conn GL, Goldberg JB. Pseudomonas aeruginosa EftM Is a Thermoregulated Methyltransferase. J Biol Chem 2015; 291:3280-90. [PMID: 26677219 DOI: 10.1074/jbc.m115.706853] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Indexed: 11/06/2022] Open
Abstract
Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen that trimethylates elongation factor-thermo-unstable (EF-Tu) on lysine 5. Lysine 5 methylation occurs in a temperature-dependent manner and is generally only seen when P. aeruginosa is grown at temperatures close to ambient (25 °C) but not at higher temperatures (37 °C). We have previously identified the gene, eftM (for EF-Tu-modifying enzyme), responsible for this modification and shown its activity to be associated with increased bacterial adhesion to and invasion of respiratory epithelial cells. Bioinformatic analyses predicted EftM to be a Class I S-adenosyl-l-methionine (SAM)-dependent methyltransferase. An in vitro methyltransferase assay was employed to show that, in the presence of SAM, EftM directly trimethylates EF-Tu. A natural variant of EftM, with a glycine to arginine substitution at position 50 in the predicted SAM-binding domain, lacks both SAM binding and enzyme activity. Mass spectrometry analysis of the in vitro methyltransferase reaction products revealed that EftM exclusively methylates at lysine 5 of EF-Tu in a distributive manner. Consistent with the in vivo temperature dependence of methylation of EF-Tu, preincubation of EftM at 37 °C abolished methyltransferase activity, whereas this activity was retained when EftM was preincubated at 25 °C. Irreversible protein unfolding at 37 °C was observed, and we propose that this instability is the molecular basis for the temperature dependence of EftM activity. Collectively, our results show that EftM is a thermolabile, SAM-dependent methyltransferase that directly trimethylates lysine 5 of EF-Tu in P. aeruginosa.
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Affiliation(s)
- Joshua P Owings
- From the Department of Pediatrics, Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep and the Emory-Children's Center for Cystic Fibrosis Research, Emory University and Children's Healthcare of Atlanta, Atlanta, Georgia 30322, the Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia 22908
| | - Emily G Kuiper
- the Department of Biochemistry and the Biochemistry, Cell, and Developmental Biology Program and
| | - Samantha M Prezioso
- From the Department of Pediatrics, Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep and the Emory-Children's Center for Cystic Fibrosis Research, Emory University and Children's Healthcare of Atlanta, Atlanta, Georgia 30322, Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Emory University School of Medicine, Atlanta, Georgia 30322, and
| | - Jeffrey Meisner
- From the Department of Pediatrics, Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep and the Emory-Children's Center for Cystic Fibrosis Research, Emory University and Children's Healthcare of Atlanta, Atlanta, Georgia 30322
| | - John J Varga
- From the Department of Pediatrics, Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep and the Emory-Children's Center for Cystic Fibrosis Research, Emory University and Children's Healthcare of Atlanta, Atlanta, Georgia 30322, the Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia 22908
| | | | | | | | | | - Sebastián Albertí
- the Instituto Universitario de Investigación en Ciencias de la Salud, Universidad de las Islas Baleares, Palma de Mallorca, 07122 Spain
| | | | - Joanna B Goldberg
- From the Department of Pediatrics, Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep and the Emory-Children's Center for Cystic Fibrosis Research, Emory University and Children's Healthcare of Atlanta, Atlanta, Georgia 30322, the Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia 22908,
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26
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Tribelli PM, Solar Venero EC, Ricardi MM, Gómez-Lozano M, Raiger Iustman LJ, Molin S, López NI. Novel Essential Role of Ethanol Oxidation Genes at Low Temperature Revealed by Transcriptome Analysis in the Antarctic Bacterium Pseudomonas extremaustralis. PLoS One 2015; 10:e0145353. [PMID: 26671564 PMCID: PMC4686015 DOI: 10.1371/journal.pone.0145353] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 12/02/2015] [Indexed: 02/06/2023] Open
Abstract
Temperature is one of the most important factors for bacterial growth and development. Cold environments are widely distributed on earth, and psychrotolerant and psychrophilic microorganisms have developed different adaptation strategies to cope with the stress derived from low temperatures. Pseudomonas extremaustralis is an Antarctic bacterium able to grow under low temperatures and to produce high amounts of polyhydroxyalkanoates (PHAs). In this work, we analyzed the genome-wide transcriptome by RNA deep-sequencing technology of early exponential cultures of P. extremaustralis growing in LB (Luria Broth) supplemented with sodium octanoate to favor PHA accumulation at 8°C and 30°C. We found that genes involved in primary metabolism, including tricarboxylic acid cycle (TCA) related genes, as well as cytochromes and amino acid metabolism coding genes, were repressed at low temperature. Among up-regulated genes, those coding for transcriptional regulatory and signal transduction proteins were over-represented at cold conditions. Remarkably, we found that genes involved in ethanol oxidation, exaA, exaB and exaC, encoding a pyrroloquinoline quinone (PQQ)-dependent ethanol dehydrogenase, the cytochrome c550 and an aldehyde dehydrogenase respectively, were up-regulated. Along with RNA-seq experiments, analysis of mutant strains for pqqB (PQQ biosynthesis protein B) and exaA were carried out. We found that the exaA and pqqB genes are essential for growth under low temperature in LB supplemented with sodium octanoate. Additionally, p-rosaniline assay measurements showed the presence of alcohol dehydrogenase activity at both 8°C and 30°C, while the activity was abolished in a pqqB mutant strain. These results together with the detection of ethanol by gas chromatography in P. extremaustralis cultures grown at 8°C support the conclusion that this pathway is important under cold conditions. The obtained results have led to the identification of novel components involved in cold adaptation mechanisms in this bacterium, suggesting for the first time a role of the ethanol oxidation pathway for bacterial growth at low temperatures.
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Affiliation(s)
- Paula M. Tribelli
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Guiraldes 2160, C1428EGA Buenos Aires, Argentina
- IQUIBICEN, CONICET, Buenos Aires, Argentina
| | | | - Martiniano M. Ricardi
- Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE-CONICET), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina
| | - Maria Gómez-Lozano
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Hørsholm, Denmark
| | - Laura J. Raiger Iustman
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Guiraldes 2160, C1428EGA Buenos Aires, Argentina
- IQUIBICEN, CONICET, Buenos Aires, Argentina
| | - Søren Molin
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Hørsholm, Denmark
| | - Nancy I. López
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Guiraldes 2160, C1428EGA Buenos Aires, Argentina
- IQUIBICEN, CONICET, Buenos Aires, Argentina
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27
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Scales BS, Erb-Downward JR, Huffnagle IM, LiPuma JJ, Huffnagle GB. Comparative genomics of Pseudomonas fluorescens subclade III strains from human lungs. BMC Genomics 2015; 16:1032. [PMID: 26644001 PMCID: PMC4672498 DOI: 10.1186/s12864-015-2261-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 11/30/2015] [Indexed: 12/22/2022] Open
Abstract
Background While the taxonomy and genomics of environmental strains from the P. fluorescens species-complex has been reported, little is known about P. fluorescens strains from clinical samples. In this report, we provide the first genomic analysis of P. fluorescens strains in which human vs. environmental isolates are compared. Results Seven P. fluorescens strains were isolated from respiratory samples from cystic fibrosis (CF) patients. The clinical strains could grow at a higher temperature (>34 °C) than has been reported for environmental strains. Draft genomes were generated for all of the clinical strains, and multi-locus sequence analysis placed them within subclade III of the P. fluorescens species-complex. All strains encoded type- II, −III, −IV, and -VI secretion systems, as well as the widespread colonization island (WCI). This is the first description of a WCI in P. fluorescens strains. All strains also encoded a complete I2/PfiT locus and showed evidence of horizontal gene transfer. The clinical strains were found to differ from the environmental strains in the number of genes involved in metal resistance, which may be a possible adaptation to chronic antibiotic exposure in the CF lung. Conclusions This is the largest comparative genomics analysis of P. fluorescens subclade III strains to date and includes the first clinical isolates. At a global level, the clinical P. fluorescens subclade III strains were largely indistinguishable from environmental P. fluorescens subclade III strains, supporting the idea that identifying strains as ‘environmental’ vs ‘clinical’ is not a phenotypic trait. Rather, strains within P. fluorescens subclade III will colonize and persist in any niche that provides the requirements necessary for growth. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-2261-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Brittan S Scales
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA. .,Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, USA.
| | - John R Erb-Downward
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA.
| | - Ian M Huffnagle
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA.
| | - John J LiPuma
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA.
| | - Gary B Huffnagle
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA. .,Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, USA.
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28
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Varga JJ, Barbier M, Mulet X, Bielecki P, Bartell JA, Owings JP, Martinez-Ramos I, Hittle LE, Davis MR, Damron FH, Liechti GW, Puchałka J, dos Santos VAPM, Ernst RK, Papin JA, Albertí S, Oliver A, Goldberg JB. Genotypic and phenotypic analyses of a Pseudomonas aeruginosa chronic bronchiectasis isolate reveal differences from cystic fibrosis and laboratory strains. BMC Genomics 2015; 16:883. [PMID: 26519161 PMCID: PMC4628258 DOI: 10.1186/s12864-015-2069-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 10/03/2015] [Indexed: 01/24/2023] Open
Abstract
Background Pseudomonas aeruginosa is an environmentally ubiquitous Gram-negative bacterium and important opportunistic human pathogen, causing severe chronic respiratory infections in patients with underlying conditions such as cystic fibrosis (CF) or bronchiectasis. In order to identify mechanisms responsible for adaptation during bronchiectasis infections, a bronchiectasis isolate, PAHM4, was phenotypically and genotypically characterized. Results This strain displays phenotypes that have been associated with chronic respiratory infections in CF including alginate over-production, rough lipopolysaccharide, quorum-sensing deficiency, loss of motility, decreased protease secretion, and hypermutation. Hypermutation is a key adaptation of this bacterium during the course of chronic respiratory infections and analysis indicates that PAHM4 encodes a mutated mutS gene responsible for a ~1,000-fold increase in mutation rate compared to wild-type laboratory strain P. aeruginosa PAO1. Antibiotic resistance profiles and sequence data indicate that this strain acquired numerous mutations associated with increased resistance levels to β-lactams, aminoglycosides, and fluoroquinolones when compared to PAO1. Sequencing of PAHM4 revealed a 6.38 Mbp genome, 5.9 % of which were unrecognized in previously reported P. aeruginosa genome sequences. Transcriptome analysis suggests a general down-regulation of virulence factors, while metabolism of amino acids and lipids is up-regulated when compared to PAO1 and metabolic modeling identified further potential differences between PAO1 and PAHM4. Conclusions This work provides insights into the potential differential adaptation of this bacterium to the lung of patients with bronchiectasis compared to other clinical settings such as cystic fibrosis, findings that should aid the development of disease-appropriate treatment strategies for P. aeruginosa infections. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-2069-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- John J Varga
- Department of Pediatrics, Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep, Children's Healthcare of Atlanta, Atlanta, GA, USA. .,Emory + Children's Center for Cystic Fibrosis Research, Emory University and Children's Healthcare of Atlanta, Atlanta, GA, USA. .,Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA.
| | - Mariette Barbier
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA. .,Department of Microbiology, Immunology and Cell Biology, West Virginia University School of Medicine, Morgantown, WV, USA.
| | - Xavier Mulet
- Servicio de Microbiología and Unidad de Investigación, Hospital Son Espases, Instituto de Investigación Sanitaria de Palma (IdISPa), Palma, de Mallorca, Spain.
| | - Piotr Bielecki
- Synthetic and Systems Biology Research Group, Helmholtz Centre for Infection Research, Braunschweig, Germany. .,Present address: Immunobiology Department, Yale University, School of Medicine, New Haven, CT, 06511, USA.
| | - Jennifer A Bartell
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA.
| | - Joshua P Owings
- Department of Pediatrics, Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep, Children's Healthcare of Atlanta, Atlanta, GA, USA. .,Emory + Children's Center for Cystic Fibrosis Research, Emory University and Children's Healthcare of Atlanta, Atlanta, GA, USA. .,Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA.
| | | | - Lauren E Hittle
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, University of Maryland, Baltimore, MD, USA.
| | - Michael R Davis
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA.
| | - F Heath Damron
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA. .,Department of Microbiology, Immunology and Cell Biology, West Virginia University School of Medicine, Morgantown, WV, USA.
| | - George W Liechti
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA.
| | - Jacek Puchałka
- Servicio de Microbiología and Unidad de Investigación, Hospital Son Espases, Instituto de Investigación Sanitaria de Palma (IdISPa), Palma, de Mallorca, Spain. .,Present address: Dr. von Hauner Children's Hospital, Ludwig Maximilians University, Munich, Germany.
| | - Vitor A P Martins dos Santos
- Systems and Synthetic Biology, Wageningen University, Wageningen, Netherlands. .,Present address: Chair of Systems and Synthetic Biology, Wageningen University, Wageningen, The Netherlands. .,Present address: LifeGlimmer GmbH, Berlin, Germany.
| | - Robert K Ernst
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, University of Maryland, Baltimore, MD, USA.
| | - Jason A Papin
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA.
| | - Sebastian Albertí
- IUNICS, University of the Balearic Islands, Palma, de Mallorca, Spain.
| | - Antonio Oliver
- Servicio de Microbiología and Unidad de Investigación, Hospital Son Espases, Instituto de Investigación Sanitaria de Palma (IdISPa), Palma, de Mallorca, Spain.
| | - Joanna B Goldberg
- Department of Pediatrics, Division of Pulmonology, Allergy/Immunology, Cystic Fibrosis and Sleep, Children's Healthcare of Atlanta, Atlanta, GA, USA. .,Emory + Children's Center for Cystic Fibrosis Research, Emory University and Children's Healthcare of Atlanta, Atlanta, GA, USA. .,Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA.
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29
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Abstract
Pathogenic bacteria sense environmental cues, including the local temperature, to control the production of key virulence factors. Thermal regulation can be achieved at the level of DNA, RNA or protein and although many virulence factors are subject to thermal regulation, the exact mechanisms of control are yet to be elucidated in many instances. Understanding how virulence factors are regulated by temperature presents a significant challenge, as gene expression and protein production are often influenced by complex regulatory networks involving multiple transcription factors in bacteria. Here we highlight some recent insights into thermal regulation of virulence in pathogenic bacteria. We focus on bacteria which cause disease in mammalian hosts, which are at a significantly higher temperature than the outside environment. We outline the mechanisms of thermal regulation and how understanding this fundamental aspect of the biology of bacteria has implications for pathogenesis and human health.
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Affiliation(s)
- Oliver Lam
- a The Sir William Dunn School of Pathology ; University of Oxford ; Oxford , UK
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30
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Wright E, Neethirajan S, Weng X. Microfluidic wound model for studying the behaviors of Pseudomonas aeruginosa in polymicrobial biofilms. Biotechnol Bioeng 2015; 112:2351-9. [PMID: 25994926 DOI: 10.1002/bit.25651] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 04/02/2015] [Accepted: 05/11/2015] [Indexed: 12/22/2022]
Abstract
Pseudomonas aeruginosa is a particularly problematic opportunistic pathogen due to its capacity to form recalcitrant biofilm structures, while cohabiting with other harmful/pathogenic species and harboring the capability to release toxins that cause tissue necrosis. Although it is now recognized that the majority of biofilm infections are polymicrobial, little is known about the complex interactions that occur within polymicrobial communities and few tools exist for studying these interactions. In this study, we have designed a microfluidic model that mimics the relevant physiological properties of wound microenvironment, while incorporating materials present in the human extracellular matrix/wound environment. Using microfluidics combined with imaging techniques, we have validated the robustness of our model comparing traditional GFP-tagging to new fluorescent staining techniques to visualize/resolve individual species within a polymicrobial habitat. We have also demonstrated that chemotactic stimuli may be incorporated into our model through specialized ports in our chamber. Our system is specifically designed for use with high resolution imaging techniques, allowing for data collection throughout the life of the biofilm and in real-time. Ultimately, this model can be used to investigate the spatio-temporal mechanobiological structures of the wound environment, and the response of the bacteria to the drug transport which will significantly contribute to our understanding of the development and progression of polymicrobial biofilm infections.
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Affiliation(s)
- Evan Wright
- BioNano Laboratory, School of Engineering, University of Guelph, Guelph, Canada, N1G 2W1
| | - Suresh Neethirajan
- BioNano Laboratory, School of Engineering, University of Guelph, Guelph, Canada, N1G 2W1.
| | - Xuan Weng
- BioNano Laboratory, School of Engineering, University of Guelph, Guelph, Canada, N1G 2W1
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Slate AR, Bandyopadhyay S, Francis KP, Papich MG, Karolewski B, Hod EA, Prestia KA. Efficacy of enrofloxacin in a mouse model of sepsis. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE : JAALAS 2014; 53:381-386. [PMID: 25199094 PMCID: PMC4113238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 11/06/2013] [Accepted: 12/06/2013] [Indexed: 06/03/2023]
Abstract
We examined the efficacy of enrofloxacin administered by 2 different routes in a mouse model of sepsis. Male CD1 mice were infected with a bioluminescent strain of enteropathogenic Escherichia coli and treated with enrofloxacin either by injection or in drinking water. Peak serum levels were evaluated by using HPLC. Mice were monitored for signs of clinical disease, and infections were monitored by using bioluminescence imaging. Serum levels of enrofloxacin and the active metabolite ciprofloxacin were greater in the group treated by injection than in controls or the groups treated by administration in drinking water. Survival of the group treated with enrofloxacin injection was greater than that of controls and groups treated with enrofloxacin in the drinking water. Bioluminescence in the group treated with enrofloxacin injection was less than that in the groups treated with oral administration at 12 h and in the groups treated orally and the control group at 16 h. According to these findings, we recommend the use of injectable enrofloxacin at 5 mg/kg SC for mice with systemic infections.
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Affiliation(s)
- Andrea R Slate
- Division of Comparative Medicine, University of South Florida, Tampa, Florida, USA
| | - Sheila Bandyopadhyay
- Laboratory of Transfusion Biology, Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | | | - Mark G Papich
- Department of Molecular Biomedical Sciences, North Carolina State University College of Veterinary Medicine, Raleigh, North Carolina, USA
| | - Brian Karolewski
- Institute of Comparative Medicine, Columbia University, New York, New York, USA
| | - Eldad A Hod
- Laboratory of Transfusion Biology, Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Kevin A Prestia
- Laboratory of Transfusion Biology, Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, New York, USA; Institute of Comparative Medicine, Columbia University, New York, New York, USA
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