1
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Liu Y, McQuillen EA, Rana PSJB, Gloag ES, Parsek MR, Wozniak DJ. A bacterial pigment provides cross-species protection from H 2O 2- and neutrophil-mediated killing. Proc Natl Acad Sci U S A 2024; 121:e2312334121. [PMID: 38170744 PMCID: PMC10786307 DOI: 10.1073/pnas.2312334121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 11/29/2023] [Indexed: 01/05/2024] Open
Abstract
Bacterial infections are often polymicrobial. Pseudomonas aeruginosa and Staphylococcus aureus cause chronic co-infections, which are more problematic than mono-species infections. Understanding the mechanisms of their interactions is crucial for treating co-infections. Staphyloxanthin (STX), a yellow pigment synthesized by the S. aureus crt operon, promotes S. aureus resistance to oxidative stress and neutrophil-mediated killing. We found that STX production by S. aureus, either as surface-grown macrocolonies or planktonic cultures, was elevated when exposed to the P. aeruginosa exoproduct, 2-heptyl-4-hydroxyquinoline N-oxide (HQNO). This was observed with both mucoid and non-mucoid P. aeruginosa strains. The induction phenotype was found in a majority of P. aeruginosa and S. aureus clinical isolates examined. When subjected to hydrogen peroxide or human neutrophils, P. aeruginosa survival was significantly higher when mixed with wild-type (WT) S. aureus, compared to P. aeruginosa alone or with an S. aureus crt mutant deficient in STX production. In a murine wound model, co-infection with WT S. aureus, but not the STX-deficient mutant, enhanced P. aeruginosa burden and disease compared to mono-infection. In conclusion, we identified a role for P. aeruginosa HQNO mediating polymicrobial interactions with S. aureus by inducing STX production, which consequently promotes resistance to the innate immune effectors H2O2 and neutrophils. These results further our understanding of how different bacterial species cooperatively cause co-infections.
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Affiliation(s)
- Yiwei Liu
- Department of Microbiology, Ohio State University, Columbus, OH43210
- Department of Microbial Infection and Immunity, Ohio State University College of Medicine, Columbus, OH43210
| | - Eleanor A. McQuillen
- Department of Health and Rehabilitation Sciences, Ohio State University College of Medicine, Columbus, OH43210
| | - Pranav S. J. B. Rana
- Department of Microbiology, Ohio State University, Columbus, OH43210
- Department of Microbial Infection and Immunity, Ohio State University College of Medicine, Columbus, OH43210
| | - Erin S. Gloag
- Department of Microbial Infection and Immunity, Ohio State University College of Medicine, Columbus, OH43210
- Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA24060
| | - Matthew R. Parsek
- Department of Microbiology, University of Washington School of Medicine, Seattle, WA98195
| | - Daniel J. Wozniak
- Department of Microbiology, Ohio State University, Columbus, OH43210
- Department of Microbial Infection and Immunity, Ohio State University College of Medicine, Columbus, OH43210
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2
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Nooranidoost M, Cogan N, Stoodley P, Gloag ES, Hussaini MY. Bayesian estimation of Pseudomonas aeruginosa viscoelastic properties based on creep responses of wild type, rugose, and mucoid variant biofilms. Biofilm 2023; 5:100133. [PMID: 37396464 PMCID: PMC10313507 DOI: 10.1016/j.bioflm.2023.100133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 05/29/2023] [Accepted: 05/31/2023] [Indexed: 07/04/2023] Open
Abstract
Pseudomonas aeruginosa biofilms are relevant for a variety of disease settings, including pulmonary infections in people with cystic fibrosis. Biofilms are initiated by individual bacteria that undergo a phenotypic switch and produce an extracellular polymeric slime (EPS). However, the viscoelastic characteristics of biofilms at different stages of formation and the contributions of different EPS constituents have not been fully explored. For this purpose, we develop and parameterize a mathematical model to study the rheological behavior of three biofilms - P. aeruginosa wild type PAO1, isogenic rugose small colony variant (RSCV), and mucoid variant biofilms against a range of experimental data. Using Bayesian inference to estimate these viscoelastic properties, we quantify the rheological characteristics of the biofilm EPS. We employ a Monte Carlo Markov Chain algorithm to estimate these properties of P. aeruginosa variant biofilms in comparison to those of wild type. This information helps us understand the rheological behavior of biofilms at different stages of their development. The mechanical properties of wild type biofilms change significantly over time and are more sensitive to small changes in their composition than the other two mutants.
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Affiliation(s)
| | - N.G. Cogan
- Department of Mathematics, Florida State University, Tallahassee, FL, USA
| | - Paul Stoodley
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
- Department of Orthopaedics, The Ohio State University, Columbus, OH, USA
- National Centre for Advanced Tribology at Southampton (nCATS), National Biofilm Innovation Centre (NBIC), Department of Mechanical Engineering, University of Southampton, UK
| | - Erin S. Gloag
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, USA
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3
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Ferguson DL, Gloag ES, Parsek MR, Wozniak DJ. Extracellular DNA enhances biofilm integrity and mechanical properties of mucoid Pseudomonas aeruginosa. J Bacteriol 2023; 205:e0023823. [PMID: 37791754 PMCID: PMC10601617 DOI: 10.1128/jb.00238-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 08/31/2023] [Indexed: 10/05/2023] Open
Abstract
Pseudomonas aeruginosa is one of the most common biofilm-forming pathogens responsible for lung infections of individuals with cystic fibrosis (CF). P. aeruginosa becomes tolerant to antimicrobials in the biofilm state and is difficult to treat. Production of extracellular polymeric substances (EPS), such as alginate and extracellular DNA (eDNA), can allow adherence to abiotic and biotic surfaces, antimicrobial evasion, and resilience to environmental pressures. Alginate-producing mucoid variants of P. aeruginosa are frequently isolated from CF airway samples and are associated with worsening patient outcomes. While eDNA is a major structural component of nonmucoid P. aeruginosa biofilms, the potential role of eDNA in mucoid biofilms is unclear. Here, we investigate how eDNA contributes to clinical mucoid biofilm physiology and integrity. We predicted that eDNA plays a structural and mechanical role in mucoid biofilms. To test this, we quantified biofilm eDNA in mucoid biofilms and used microscopy and rheology to visualize eDNA and detect changes in biofilm structure and mechanics upon DNaseI treatment. We showed that biofilm eDNA abundance is diverse across clinical mucoid strains and observed a temporal increase in foci of eDNA within intact mucoid biofilms. Increased cell dispersal and reduced biomass were also observed following DNaseI treatment of mucoid biofilms. Degradation of eDNA also impacted the mechanical integrity of mucoid biofilms by increasing the stiffness and decreasing the cohesion of the biofilm. These findings advance our understanding of clinical mucoid P. aeruginosa biofilms and facilitate the development of new approaches to target biofilms by exploiting the functions of EPS components. IMPORTANCE Understanding the role of eDNA in mucoid Pseudomonas aeruginosa biofilms will lead to therapeutic strategies that combat the biophysical and structural function of EPS for the eradication of bacteria in mucoid biofilms during chronic infections. This knowledge can be used to further identify unknown matrix component interactions within pathogenic biofilm-forming clinical isolates.
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Affiliation(s)
- Danielle L. Ferguson
- Department of Microbial Infection and Immunity, Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Erin S. Gloag
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, USA
| | - Matthew R. Parsek
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Daniel J. Wozniak
- Department of Microbial Infection and Immunity, Microbiology, The Ohio State University, Columbus, Ohio, USA
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4
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Gloag ES, Khosravi Y, Masters JG, Wozniak DJ, Amorin Daep C, Stoodley P. A Combination of Zinc and Arginine Disrupt the Mechanical Integrity of Dental Biofilms. Microbiol Spectr 2023; 11:e0335122. [PMID: 36472465 PMCID: PMC9927089 DOI: 10.1128/spectrum.03351-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 11/18/2022] [Indexed: 12/12/2022] Open
Abstract
Mechanical cleaning remains the standard of care for maintaining oral hygiene. However, mechanical cleaning is often augmented with active therapeutics that further promote oral health. A dentifrice, consisting of the "Dual Zinc plus Arginine" (DZA) technology, was found to be effective at controlling bacteria using in vitro laboratory studies, translating to clinical efficacy to deliver plaque and gingivitis reduction benefits. Here, we used biophysical analyses and confocal laser scanning microscopy to understand how a DZA dentifrice impacted the mechanical properties of dental plaque biofilms and determine if changes to biofilm rheology enhanced the removal of dental plaque. Using both uniaxial mechanical indentation and an adapted rotating-disc rheometry assay, it was found that DZA treatment compromised biofilm mechanical integrity, resulting in the biofilm being more susceptible to removal by shear forces compared to treatment with either arginine or zinc alone. Confocal laser scanning microscopy revealed that DZA treatment reduced the amount of extracellular polymeric slime within the biofilm, likely accounting for the reduced mechanical properties. We propose a model where arginine facilitates the entry of zinc into the biofilm, resulting in additive effects of the two activities toward dental plaque biofilms. Together, our results support the use of a dentifrice containing Dual Zinc plus Arginine as part of daily oral hygiene regimens. IMPORTANCE Mechanical removal of dental plaque is augmented with therapeutic compounds to promote oral health. A dentifrice containing the ingredients zinc and arginine has shown efficacy at reducing dental plaque both in vitro and in vivo. However, how these active compounds interact together to facilitate dental plaque removal is unclear. Here, we used a combination of biophysical analyses and microscopy to demonstrate that combined treatment with zinc and arginine targets the matrix of dental plaque biofilms, which destabilized the mechanical integrity of these microbial communities, making them more susceptible to removal by shear forces.
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Affiliation(s)
- Erin S. Gloag
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, Ohio, USA
| | - Yalda Khosravi
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, Ohio, USA
| | - James G. Masters
- Colgate-Palmolive Technology Center, Piscataway, New Jersey, USA
| | - Daniel J. Wozniak
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, Ohio, USA
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | | | - Paul Stoodley
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, Ohio, USA
- Department of Orthopaedics, The Ohio State University, Columbus, Ohio, USA
- National Biofilm Innovation Centre (NBIC), University of Southampton, Southampton, United Kingdom
- National Centre for Advanced Tribology at Southampton (nCATS), Mechanical Engineering, University of Southampton, Southampton, United Kingdom
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5
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Razvi E, Whitfield GB, Reichhardt C, Dreifus JE, Willis AR, Gluscencova OB, Gloag ES, Awad TS, Rich JD, da Silva DP, Bond W, Le Mauff F, Sheppard DC, Hatton BD, Stoodley P, Reinke AW, Boulianne GL, Wozniak DJ, Harrison JJ, Parsek MR, Howell PL. Glycoside hydrolase processing of the Pel polysaccharide alters biofilm biomechanics and Pseudomonas aeruginosa virulence. NPJ Biofilms Microbiomes 2023; 9:7. [PMID: 36732330 PMCID: PMC9894940 DOI: 10.1038/s41522-023-00375-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 01/16/2023] [Indexed: 02/04/2023] Open
Abstract
Pel exopolysaccharide biosynthetic loci are phylogenetically widespread biofilm matrix determinants in bacteria. In Pseudomonas aeruginosa, Pel is crucial for cell-to-cell interactions and reducing susceptibility to antibiotic and mucolytic treatments. While genes encoding glycoside hydrolases have long been linked to biofilm exopolysaccharide biosynthesis, their physiological role in biofilm development is unclear. Here we demonstrate that the glycoside hydrolase activity of P. aeruginosa PelA decreases adherent biofilm biomass and is responsible for generating the low molecular weight secreted form of the Pel exopolysaccharide. We show that the generation of secreted Pel contributes to the biomechanical properties of the biofilm and decreases the virulence of P. aeruginosa in Caenorhabditis elegans and Drosophila melanogaster. Our results reveal that glycoside hydrolases found in exopolysaccharide biosynthetic systems can help shape the soft matter attributes of a biofilm and propose that secreted matrix components be referred to as matrix associated to better reflect their influence.
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Affiliation(s)
- Erum Razvi
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Gregory B Whitfield
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
- Département de Microbiologie, Infectiologie, et Immunologie, Faculté de Médecine Université de Montréal, Montréal, QC, Canada
| | - Courtney Reichhardt
- Department of Microbiology, University of Washington, Seattle, WA, USA
- Department of Chemistry, Washington University, St. Louis, MO, USA
| | - Julia E Dreifus
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Alexandra R Willis
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Oxana B Gluscencova
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Erin S Gloag
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, 43210, USA
- Department of Biomedical Sciences and Pathobiology, VA-MD College of Veterinary Medicine, Virginia Tech, VA, 24061, USA
| | - Tarek S Awad
- Department of Materials Science and Engineering, University of Toronto, Toronto, ON, Canada
| | - Jacquelyn D Rich
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Daniel Passos da Silva
- Department of Microbiology, University of Washington, Seattle, WA, USA
- BioVectra Inc. 11 Aviation, Charlottetown, PE, Canada
| | - Whitney Bond
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - François Le Mauff
- Department of Microbiology and Immunology, Faculty of Medicine, McGill University, Montreal, QC, Canada
- Infectious Disease and Immunity in Global Health, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- McGill Interdisciplinary Initiative in Infection and Immunity, Montreal, QC, Canada
| | - Donald C Sheppard
- Department of Microbiology and Immunology, Faculty of Medicine, McGill University, Montreal, QC, Canada
- Infectious Disease and Immunity in Global Health, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- McGill Interdisciplinary Initiative in Infection and Immunity, Montreal, QC, Canada
| | - Benjamin D Hatton
- Department of Materials Science and Engineering, University of Toronto, Toronto, ON, Canada
| | - Paul Stoodley
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, 43210, USA
- Department of Orthopedics, The Ohio State University, Columbus, OH, 43210, USA
- National Biofilm Innovation Centre (NBIC) and National Centre for Advanced Tribology at Southampton (nCATS), University of Southampton, Southampton, SO17 1BJ, UK
- Department of Microbiology, The Ohio State University, Columbus, OH, 43210, USA
| | - Aaron W Reinke
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Gabrielle L Boulianne
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Daniel J Wozniak
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, 43210, USA
- Department of Microbiology, The Ohio State University, Columbus, OH, 43210, USA
| | - Joe J Harrison
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Matthew R Parsek
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - P Lynne Howell
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, ON, Canada.
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada.
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6
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Rana PSJB, Gloag ES, Wozniak DJ. Standardized In vitro Assays to Visualize and Quantify Interactions between Human Neutrophils and Staphylococcus aureus Biofilms. J Vis Exp 2022. [PMID: 35758715 DOI: 10.3791/63773] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Neutrophils are the first line of defense deployed by the immune system during microbial infection. In vivo, neutrophils are recruited to the site of infection where they use processes such as phagocytosis, production of reactive oxygen and nitrogen species (ROS, RNS, respectively), NETosis (neutrophil extracellular trap), and degranulation to kill microbes and resolve the infection. Interactions between neutrophils and planktonic microbes have been extensively studied. There have been emerging interests in studying infections caused by biofilms in recent years. Biofilms exhibit properties, including tolerance to killing by neutrophils, distinct from their planktonic-grown counterparts. With the successful establishment of both in vitro and in vivo biofilm models, interactions between these microbial communities with different immune cells can now be investigated. Here, techniques that use a combination of traditional biofilm models and well-established neutrophil activity assays are tailored specifically to study neutrophil and biofilm interactions. Wide-field fluorescence microscopy is used to monitor the localization of neutrophils in biofilms. These biofilms are grown in static conditions, followed by the addition of neutrophils derived from human peripheral blood. The samples are stained with appropriate dyes prior to visualization under the microscope. Additionally, the production of ROS, which is one of the many neutrophil responses against pathogens, is quantified in the presence of a biofilm. The addition of immune cells to this established system will expand the understanding of host-pathogen interactions while ensuring the use of standardized and optimized conditions to measure these processes accurately.
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Affiliation(s)
| | - Erin S Gloag
- Department of Microbial Infection and Immunity, The Ohio State University
| | - Daniel J Wozniak
- Department of Microbiology, The Ohio State University; Department of Microbial Infection and Immunity, The Ohio State University;
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7
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Liu Y, Gloag ES, Hill PJ, Parsek MR, Wozniak DJ. Interbacterial Antagonism Mediated by a Released Polysaccharide. J Bacteriol 2022; 204:e0007622. [PMID: 35446119 PMCID: PMC9112932 DOI: 10.1128/jb.00076-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 04/06/2022] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas aeruginosa and Staphylococcus aureus are two common pathogens causing chronic infections in the lungs of people with cystic fibrosis (CF) and in wounds, suggesting that these two organisms coexist in vivo. However, P. aeruginosa utilizes various mechanisms to antagonize S. aureus when these organisms are grown together in vitro. Here, we suggest a novel role for Psl in antagonizing S. aureus growth. Psl is an exopolysaccharide that exists in both cell-associated and cell-free forms and is important for biofilm formation in P. aeruginosa. When grown in planktonic coculture with a P. aeruginosa psl mutant, S. aureus had increased survival compared to when it was grown with wild-type P. aeruginosa. We found that cell-free Psl was critical for the killing, as purified cell-free Psl was sufficient to kill S. aureus. Transmission electron microscopy of S. aureus treated with Psl revealed disrupted cell envelopes, suggesting that Psl causes S. aureus cell lysis. This was independent of known mechanisms used by P. aeruginosa to antagonize S. aureus. Cell-free Psl could also promote S. aureus killing during growth in in vivo-like conditions. We also found that Psl production in P. aeruginosa CF clinical isolates positively correlated with the ability to kill S. aureus. This could be a result of P. aeruginosa coevolution with S. aureus in CF lungs. In conclusion, this study defines a novel role for P. aeruginosa Psl in killing S. aureus, potentially impacting the coexistence of these two opportunistic pathogens in vivo. IMPORTANCE Pseudomonas aeruginosa and Staphylococcus aureus are two important opportunistic human pathogens commonly coisolated from clinical samples. However, P. aeruginosa can utilize various mechanisms to antagonize S. aureus in vitro. Here, we investigated the interactions between these two organisms and report a novel role for P. aeruginosa exopolysaccharide Psl in killing S. aureus. We found that cell-free Psl could kill S. aureus in vitro, possibly by inducing cell lysis. This was also observed in conditions reflective of in vivo scenarios. In accord with this, Psl production in P. aeruginosa clinical isolates positively correlated with their ability to kill S. aureus. Together, our data suggest a role for Psl in affecting the coexistence of P. aeruginosa and S. aureus in vivo.
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Affiliation(s)
- Yiwei Liu
- Department of Microbiology, Ohio State University, Columbus, Ohio, USA
- Department of Microbial Infection and Immunity, Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Erin S. Gloag
- Department of Microbial Infection and Immunity, Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Preston J. Hill
- Department of Microbial Infection and Immunity, Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Matthew R. Parsek
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Daniel J. Wozniak
- Department of Microbiology, Ohio State University, Columbus, Ohio, USA
- Department of Microbial Infection and Immunity, Ohio State University College of Medicine, Columbus, Ohio, USA
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8
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Mejia OR, Gloag ES, Li J, Ruane-Foster M, Claeys TA, Farkas D, Farkas L, Xin G, Robinson RT. Mice infected with Mycobacterium tuberculosis are resistant to secondary infection with SARS-CoV-2. The Journal of Immunology 2022. [DOI: 10.4049/jimmunol.208.supp.58.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Abstract
Mycobacterium tuberculosis (Mtb)and SARS-CoV-2 (CoV2) are the leading causes of death due to infectious disease; however, little is known regarding the immunological environment in the Mtb/CoV2 coinfected lung. The goal of this study was to use a mouse model of Mtb/CoV2 coinfection to determine if CoV2 affects Mtb bacterial burden and/or alters the lung immune profile. Using lung collected from human ACE2 transgenic (K18-hACE2) mice infected with both pathogens (Mtb only, SARS-CoV-2 only, and Mtb/SARS-CoV-2 co-infected), we evaluated immune gene expression, cytokine production, and bacterial burden. Surprisingly, these data show that Mtb suppresses CoV2 -related weight loss and lung viral burden in the human ACE2 transgenic mouse model. We also report a reduction in lung interferon gamma production and expression in coinfected mice compared to the Mtb only infected group, suggesting a possible altered T cell profile in the coinfected group. To determine whether Mtb-induced resistance to CoV2 was specific to the ACE2 transgenic model of COVID19, we performed the same set of experiments using a second mouse model of COVID19: Mouse Adapted SARS-CoV-2 (MACoV2) infection of C57BL/6 (B6) mice.
In both model systems, Mtb-infected mice were resistant to secondary CoV2 infection and its pathological consequences, and CoV2 infection did not affect Mtb burdens. Single cell RNA sequencing of coinfected and monoinfected lungs demonstrated the resistance of Mtb-infected mice is associated with expansion of T and B cell subsets upon viral challenge. Collectively, these data demonstrate that Mtb infection conditions the lung environment in a manner that is not conducive to CoV2 survival.
Supported by OSU Advancing Research in Infection and Immunity Fellowship Award
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Affiliation(s)
- Oscar Rosas Mejia
- 1Microbial, Infection & Immunity, The Ohio State University College of Medicine
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9
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Rosas Mejia O, Gloag ES, Li J, Ruane-Foster M, Claeys TA, Farkas D, Wang SH, Farkas L, Xin G, Robinson RT. Mice infected with Mycobacterium tuberculosis are resistant to acute disease caused by secondary infection with SARS-CoV-2. PLoS Pathog 2022; 18:e1010093. [PMID: 35325013 PMCID: PMC8946739 DOI: 10.1371/journal.ppat.1010093] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/23/2022] [Indexed: 12/22/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) and SARS-CoV-2 (CoV2) are the leading causes of death due to infectious disease. Although Mtb and CoV2 both cause serious and sometimes fatal respiratory infections, the effect of Mtb infection and its associated immune response on secondary infection with CoV2 is unknown. To address this question we applied two mouse models of COVID19, using mice which were chronically infected with Mtb. In both model systems, Mtb-infected mice were resistant to the pathological consequences of secondary CoV2 infection, and CoV2 infection did not affect Mtb burdens. Single cell RNA sequencing of coinfected and monoinfected lungs demonstrated the resistance of Mtb-infected mice is associated with expansion of T and B cell subsets upon viral challenge. Collectively, these data demonstrate that Mtb infection conditions the lung environment in a manner that is not conducive to CoV2 survival. Mycobacterium tuberculosis (Mtb) and SARS-CoV-2 (CoV2) are distinct organisms which both cause lung disease. We report the surprising observation that Mtb-infected mice are resistant to secondary infection with CoV2, with no impact on Mtb burden and resistance associating with lung T and B cell expansion.
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Affiliation(s)
| | | | | | | | | | - Daniela Farkas
- Department of Internal Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Davis Heart and Lung Research Institute
| | - Shu-Hua Wang
- Department of Infectious Disease, The Ohio State University, Columbus, Ohio, United States of America
| | - Laszlo Farkas
- Department of Internal Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Davis Heart and Lung Research Institute
| | - Gang Xin
- Department of Microbial Infection and Immunity
- Pelotonia Institute for Immuno-Oncology
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10
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Gloag ES, Wozniak DJ, Wolf KL, Masters JG, Daep CA, Stoodley P. Arginine Induced Streptococcus gordonii Biofilm Detachment Using a Novel Rotating-Disc Rheometry Method. Front Cell Infect Microbiol 2021; 11:784388. [PMID: 34805002 PMCID: PMC8602906 DOI: 10.3389/fcimb.2021.784388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 10/21/2021] [Indexed: 11/13/2022] Open
Abstract
Oral diseases are one of the most common pathologies affecting human health. These diseases are typically associated with dental plaque-biofilms, through either build-up of the biofilm or dysbiosis of the microbial community. Arginine can disrupt dental plaque-biofilms, and maintain plaque homeostasis, making it an ideal therapeutic to combat the development of oral disease. Despite our understanding of the actions of arginine towards dental plaque-biofilms, it is still unclear how or if arginine effects the mechanical integrity of the dental plaque-biofilm. Here we adapted a rotating-disc rheometry assay, a method used to quantify marine biofilm fouling, to study how arginine treatment of Streptococcus gordonii biofilms influences biofilm detachment from surfaces. We demonstrate that the assay is highly sensitive at quantifying the presence of biofilm and the detachment or rearrangement of the biofilm structure as a function of shear stress. We demonstrate that arginine treatment leads to earlier detachment of the biofilm, indicating that arginine treatment weakens the biofilm, making it more susceptible to removal by shear stresses. Finally, we demonstrate that the biofilm disrupting affect is specific to arginine, and not a general property of amino acids, as S. gordonii biofilms treated with either glycine or lysine had mechanical properties similar to untreated biofilms. Our results add to the understanding that arginine targets biofilms by multifaceted mechanisms, both metabolic and physical, further promoting the potential of arginine as an active compound in dentifrices to maintain oral health.
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Affiliation(s)
- Erin S Gloag
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, United States
| | - Daniel J Wozniak
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, United States.,Department of Microbiology, The Ohio State University, Columbus, OH, United States
| | - Kevin L Wolf
- Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, OH, United States
| | - James G Masters
- Colgate-Palmolive Technology Center, Piscataway, NJ, United States
| | | | - Paul Stoodley
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, United States.,Department of Orthopedics, The Ohio State University, Columbus, OH, United States.,National Biofilm Innovation Centre (NBIC) and National Centre for Advanced Tribology at Southampton (nCATS), University of Southampton, Southampton, United Kingdom
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11
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Buzzo JR, Devaraj A, Gloag ES, Jurcisek JA, Robledo-Avila F, Kesler T, Wilbanks K, Mashburn-Warren L, Balu S, Wickham J, Novotny LA, Stoodley P, Bakaletz LO, Goodman SD. Z-form extracellular DNA is a structural component of the bacterial biofilm matrix. Cell 2021; 184:5740-5758.e17. [PMID: 34735796 DOI: 10.1016/j.cell.2021.10.010] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 08/03/2021] [Accepted: 10/12/2021] [Indexed: 12/30/2022]
Abstract
Biofilms are community architectures adopted by bacteria inclusive of a self-formed extracellular matrix that protects resident bacteria from diverse environmental stresses and, in many species, incorporates extracellular DNA (eDNA) and DNABII proteins for structural integrity throughout biofilm development. Here, we present evidence that this eDNA-based architecture relies on the rare Z-form. Z-form DNA accumulates as biofilms mature and, through stabilization by the DNABII proteins, confers structural integrity to the biofilm matrix. Indeed, substances known to drive B-DNA into Z-DNA promoted biofilm formation whereas those that drive Z-DNA into B-DNA disrupted extant biofilms. Importantly, we demonstrated that the universal bacterial DNABII family of proteins stabilizes both bacterial- and host-eDNA in the Z-form in situ. A model is proposed that incorporates the role of Z-DNA in biofilm pathogenesis, innate immune response, and immune evasion.
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Affiliation(s)
- John R Buzzo
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Aishwarya Devaraj
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Erin S Gloag
- Department of Orthopedics, Ohio State University, Columbus, OH 43210, USA
| | - Joseph A Jurcisek
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Frank Robledo-Avila
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Theresa Kesler
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Kathryn Wilbanks
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Lauren Mashburn-Warren
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Sabarathnam Balu
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Joseph Wickham
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Laura A Novotny
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Paul Stoodley
- Department of Orthopedics, Ohio State University, Columbus, OH 43210, USA; Department of Microbial Infection and Immunity, Ohio State University, Columbus, OH 43210, USA; National Centre for Advanced Tribology at Southampton, University of Southampton, Southampton S017 1BJ, UK
| | - Lauren O Bakaletz
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA; Department of Pediatrics, College of Medicine, Ohio State University, Columbus, OH 43210, USA.
| | - Steven D Goodman
- Center for Microbial Pathogenesis, Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH 43205, USA; Department of Pediatrics, College of Medicine, Ohio State University, Columbus, OH 43210, USA.
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12
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Mejia OR, Gloag ES, Li J, Ruane-Foster M, Claeys TA, Farkas D, Farkas L, Xin G, Robinson RT. Mice infected with Mycobacterium tuberculosis are resistant to secondary infection with SARS-CoV-2. bioRxiv 2021:2021.11.09.467862. [PMID: 34790981 PMCID: PMC8597884 DOI: 10.1101/2021.11.09.467862] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
UNLABELLED Mycobacterium tuberculosis (Mtb) and SARS-CoV-2 (CoV2) are the leading causes of death due to infectious disease. Although Mtb and CoV2 both cause serious and sometimes fatal respiratory infections, the effect of Mtb infection and its associated immune response on secondary infection with CoV2 is unknown. To address this question we applied two mouse models of COVID19, using mice which were chronically infected with Mtb. In both model systems, Mtb-infected mice were resistant to secondary CoV2 infection and its pathological consequences, and CoV2 infection did not affect Mtb burdens. Single cell RNA sequencing of coinfected and monoinfected lungs demonstrated the resistance of Mtb-infected mice is associated with expansion of T and B cell subsets upon viral challenge. Collectively, these data demonstrate that Mtb infection conditions the lung environment in a manner that is not conducive to CoV2 survival. AUTHOR SUMMARY Mycobacterium tuberculosis (Mtb) and SARS-CoV-2 (CoV2) are distinct organisms which both cause lung disease. We report the surprising observation that Mtb-infected mice are resistant to secondary infection with CoV2, with no impact on Mtb burden and resistance associating with lung T and B cell expansion.
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Affiliation(s)
- Oscar Rosas Mejia
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
| | - Erin S Gloag
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
| | - Jianying Li
- Pelotonia Institute for Immuno-Oncology, The Ohio State University, Columbus, OH, USA
| | - Marisa Ruane-Foster
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
| | - Tiffany A Claeys
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
| | - Daniela Farkas
- Department of Internal Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
| | - Laszlo Farkas
- Department of Internal Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
| | - Gang Xin
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
- Pelotonia Institute for Immuno-Oncology, The Ohio State University, Columbus, OH, USA
| | - Richard T Robinson
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
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13
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Marshall CW, Gloag ES, Lim C, Wozniak DJ, Cooper VS. Rampant prophage movement among transient competitors drives rapid adaptation during infection. Sci Adv 2021; 7:7/29/eabh1489. [PMID: 34272240 PMCID: PMC8284892 DOI: 10.1126/sciadv.abh1489] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 06/03/2021] [Indexed: 05/11/2023]
Abstract
Interactions between bacteria, their close competitors, and viral parasites are common in infections, but understanding of these eco-evolutionary dynamics is limited. Most examples of adaptations caused by phage lysogeny are through the acquisition of new genes. However, integrated prophages can also insert into functional genes and impart a fitness benefit by disrupting their expression, a process called active lysogeny. Here, we show that active lysogeny can fuel rapid, parallel adaptations in establishing a chronic infection. These recombination events repeatedly disrupted genes encoding global regulators, leading to increased cyclic di-GMP levels and elevated biofilm production. The implications of prophage-mediated adaptation are broad, as even transient members of microbial communities can alter the course of evolution and generate persistent phenotypes associated with poor clinical outcomes.
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Affiliation(s)
| | - Erin S Gloag
- Department of Microbial Infection and Immunity, Ohio State University, Columbus, OH, USA
| | - Christina Lim
- Department of Biological Sciences, Marquette University, Milwaukee, WI, USA
| | - Daniel J Wozniak
- Department of Microbial Infection and Immunity, Ohio State University, Columbus, OH, USA
- Department of Microbiology, Ohio State University, Columbus, OH, USA
| | - Vaughn S Cooper
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, PA, USA.
- Center for Evolutionary Biology and Medicine, University of Pittsburgh, Pittsburgh, PA, USA
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14
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Gloag ES, Wozniak DJ, Stoodley P, Hall-Stoodley L. Mycobacterium abscessus biofilms have viscoelastic properties which may contribute to their recalcitrance in chronic pulmonary infections. Sci Rep 2021; 11:5020. [PMID: 33658597 PMCID: PMC7930093 DOI: 10.1038/s41598-021-84525-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 02/10/2021] [Indexed: 12/11/2022] Open
Abstract
Mycobacterium abscessus is emerging as a cause of recalcitrant chronic pulmonary infections, particularly in people with cystic fibrosis (CF). Biofilm formation has been implicated in the pathology of this organism, however the role of biofilm formation in infection is unclear. Two colony-variants of M. abscessus are routinely isolated from CF samples, smooth (MaSm) and rough (MaRg). These two variants display distinct colony morphologies due to the presence (MaSm) or absence (MaRg) of cell wall glycopeptidolipids (GPLs). We hypothesized that MaSm and MaRg variant biofilms might have different mechanical properties. To test this hypothesis, we performed uniaxial mechanical indentation, and shear rheometry on MaSm and MaRg colony-biofilms. We identified that MaRg biofilms were significantly stiffer than MaSm under a normal force, while MaSm biofilms were more pliant compared to MaRg, under both normal and shear forces. Furthermore, using theoretical indices of mucociliary and cough clearance, we identified that M. abscessus biofilms may be more resistant to mechanical forms of clearance from the lung, compared to another common pulmonary pathogen, Pseudomonas aeruginosa. Thus, the mechanical properties of M. abscessus biofilms may contribute to the persistent nature of pulmonary infections caused by this organism.
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Affiliation(s)
- Erin S Gloag
- Department of Microbial Infection and Immunity, The Ohio State University, 711 Biomedical Research Tower, 460 W 12th Avenue, Columbus, OH, USA
| | - Daniel J Wozniak
- Department of Microbial Infection and Immunity, The Ohio State University, 711 Biomedical Research Tower, 460 W 12th Avenue, Columbus, OH, USA.,Department of Microbiology, The Ohio State University, Columbus, OH, 43210, USA
| | - Paul Stoodley
- Department of Microbial Infection and Immunity, The Ohio State University, 711 Biomedical Research Tower, 460 W 12th Avenue, Columbus, OH, USA.,Department of Orthopedics, The Ohio State University, Columbus, OH, 43210, USA.,National Biofilm Innovation Centre (NBIC) and National Centre for Advanced Tribology at Southampton (nCATS), University of Southampton, Southampton, SO17 1BJ, UK
| | - Luanne Hall-Stoodley
- Department of Microbial Infection and Immunity, The Ohio State University, 711 Biomedical Research Tower, 460 W 12th Avenue, Columbus, OH, USA.
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15
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Khosravi Y, Kandukuri RDP, Palmer SR, Gloag ES, Borisov SM, Starke EM, Ward MT, Kumar P, de Beer D, Chennu A, Stoodley P. Correction to: Use of an oxygen planar optode to assess the effect of high velocity microsprays on oxygen penetration in a human dental biofilms in-vitro. BMC Oral Health 2020; 20:247. [PMID: 32887584 PMCID: PMC7487917 DOI: 10.1186/s12903-020-01236-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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16
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Gloag ES, Fabbri S, Wozniak DJ, Stoodley P. Biofilm mechanics: Implications in infection and survival. Biofilm 2020; 2:100017. [PMID: 33447803 PMCID: PMC7798440 DOI: 10.1016/j.bioflm.2019.100017] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 12/06/2019] [Accepted: 12/09/2019] [Indexed: 12/18/2022] Open
Abstract
It has long been recognized that biofilms are viscoelastic materials, however the importance of this attribute to the survival and persistence of these microbial communities is yet to be fully realized. Here we review work, which focuses on understanding biofilm mechanics and put this knowledge in the context of biofilm survival, particularly for biofilm-associated infections. We note that biofilm viscoelasticity may be an evolved property of these communities, and that the production of multiple extracellular polymeric slime components may be a way to ensure the development of biofilms with complex viscoelastic properties. We discuss viscoelasticity facilitating biofilm survival in the context of promoting the formation of larger and stronger biofilms when exposed to shear forces, promoting fluid-like behavior of the biofilm and subsequent biofilm expansion by viscous flow, and enabling resistance to both mechanical and chemical methods of clearance. We conclude that biofilm viscoelasticity contributes to the virulence of chronic biofilm infections.
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Affiliation(s)
- Erin S. Gloag
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, 43210, USA
| | | | - Daniel J. Wozniak
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, 43210, USA
- Department of Microbiology, The Ohio State University, Columbus, OH, 43210, USA
| | - Paul Stoodley
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, 43210, USA
- Department of Microbiology, The Ohio State University, Columbus, OH, 43210, USA
- Department of Orthopedics, The Ohio State University, Columbus, OH, 43210, USA
- National Biofilm Innovation Centre (NBIC) and National Centre for Advanced Tribology at Southampton (nCATS), University of Southampton, Southampton, SO17 1BJ, UK
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17
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Khosravi Y, Kandukuri RDP, Palmer SR, Gloag ES, Borisov SM, Starke EM, Ward MT, Kumar P, de Beer D, Chennu A, Stoodley P. Use of an oxygen planar optode to assess the effect of high velocity microsprays on oxygen penetration in a human dental biofilms in-vitro. BMC Oral Health 2020; 20:230. [PMID: 32825831 PMCID: PMC7441732 DOI: 10.1186/s12903-020-01217-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 08/12/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Dental plaque biofilms are the causative agents of caries, gingivitis and periodontitis. Both mechanical and chemical strategies are used in routine oral hygiene strategies to reduce plaque build-up. If allowed to mature biofilms can create anoxic microenvironments leading to communities which harbor pathogenic Gram-negative anaerobes. When subjected to high velocity fluid jets and sprays biofilms can be fluidized which disrupts the biofilm structure and allows the more efficient delivery of antimicrobial agents. METHODS To investigate how such jets may disrupt anoxic niches in the biofilm, we used planar optodes to measure the dissolved oxygen (DO) concentration at the base of in-vitro biofilms grown from human saliva and dental plaque. These biofilms were subject to "shooting" treatments with a commercial high velocity microspray (HVM) device. RESULTS HVM treatment resulted in removal of much of the biofilm and a concurrent rapid shift from anoxic to oxic conditions at the base of the surrounding biofilm. We also assessed the impact of HVM treatment on the microbial community by tracking 7 target species by qPCR. There was a general reduction in copy numbers of the universal 16S RNA by approximately 95%, and changes of individual species in the target region ranged from approximately 1 to 4 log reductions. CONCLUSION We concluded that high velocity microsprays removed a sufficient amount of biofilm to disrupt the anoxic region at the biofilm-surface interface.
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Affiliation(s)
- Yalda Khosravi
- Department of Microbial Infection and Immunity, Ohio State University, Columbus, USA
| | | | - Sara R Palmer
- College of Dentistry, The Ohio State University, Columbus, OH, USA
| | - Erin S Gloag
- Department of Microbial Infection and Immunity, Ohio State University, Columbus, USA
| | - Sergey M Borisov
- Institute of Analytical Chemistry and Food Chemistry Graz University of Technology Stremayrgasse, Graz, Austria
| | | | - Marilyn T Ward
- Philips Oral Healthcare, Bothell, Washington, 98021, USA
| | - Purnima Kumar
- College of Dentistry, The Ohio State University, Columbus, OH, USA
| | - Dirk de Beer
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Arjun Chennu
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Paul Stoodley
- Department of Microbial Infection and Immunity, Ohio State University, Columbus, USA. .,Department Orthopaedics, Ohio State University, Columbus, USA. .,National Centre for Advanced Tribology (nCATS), Mechanical Engineering, University of Southampton, Southampton, UK.
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18
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Gloag ES, Marshall CW, Snyder D, Lewin GR, Harris JS, Santos-Lopez A, Chaney SB, Whiteley M, Cooper VS, Wozniak DJ. Pseudomonas aeruginosa Interstrain Dynamics and Selection of Hyperbiofilm Mutants during a Chronic Infection. mBio 2019; 10:e01698-19. [PMID: 31409682 PMCID: PMC6692513 DOI: 10.1128/mbio.01698-19] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 07/10/2019] [Indexed: 12/14/2022] Open
Abstract
Opportunistic pathogens establishing new infections experience strong selection to adapt, often favoring mutants that persist. Capturing this initial dynamic is critical for identifying the first adaptations that drive pathogenesis. Here we used a porcine full-thickness burn wound model of chronic infection to study the evolutionary dynamics of diverse Pseudomonas aeruginosa infections. Wounds were infected with a mixed community of six P. aeruginosa strains, including the model PA14 strain (PA14-1), and biopsies taken at 3, 14, and 28 days postinfection. Hyperbiofilm-forming rugose small-colony variants (RSCVs) were the earliest and predominant phenotypic variant. These variants were detected on day 3 and persisted, with the majority evolved from PA14-1. Whole-genome sequencing of PA14-1 RSCV isolates revealed driver mutations exclusively in the wsp pathway, conferring hyperbiofilm phenotypes. Several of the wsp mutant RSCVs also acquired CRISPR-Cas adaptive immunity to prophages isolated from the P. aeruginosa wound isolate (B23-2) that was also present in the inoculum. These observations emphasize the importance of interstrain dynamics and the role of lysogenic phages in the survival of an invading pathogen. Rather than being a side effect of chronicity, the rapid rise of RSCVs in wounds is evidence of positive selection on the Wsp chemosensory system to produce mutants with elevated biofilm formation capacity. We predict that RSCVs provide a level of phenotypic diversity to the infecting bacterial community and are common, early adaptations during infections. This would likely have significant consequences for clinical outcomes.IMPORTANCE Bacteria adapt to infections by evolving variants that are more fit and persistent. These recalcitrant variants are typically observed in chronic infections. However, it is unclear when and why these variants evolve. To address these questions, we used a porcine chronic wound model to study the evolutionary dynamics of Pseudomonas aeruginosa in a mixed-strain infection. We isolated hyperbiofilm variants that persisted early in the infection. Interstrain interactions were also observed, where adapted variants acquired CRISPR-mediated immunity to phages. We show that when initiating infection, P. aeruginosa experiences strong positive selection for hyperbiofilm phenotypes produced by mutants of a single chemosensory system, the Wsp pathway. We predict that hyperbiofilm variants are early adaptations to infection and that interstrain interactions may influence bacterial burden and infection outcomes.
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Affiliation(s)
- Erin S Gloag
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, Ohio, USA
| | - Christopher W Marshall
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Center for Evolutionary Biology and Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Daniel Snyder
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Center for Evolutionary Biology and Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Gina R Lewin
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
- Emory-Children's Cystic Fibrosis Center, Atlanta, Georgia, USA
| | - Jacob S Harris
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, Ohio, USA
| | - Alfonso Santos-Lopez
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Center for Evolutionary Biology and Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sarah B Chaney
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, Ohio, USA
| | - Marvin Whiteley
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
- Emory-Children's Cystic Fibrosis Center, Atlanta, Georgia, USA
| | - Vaughn S Cooper
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Center for Evolutionary Biology and Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Daniel J Wozniak
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, Ohio, USA
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
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19
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Gloag ES, German GK, Stoodley P, Wozniak DJ. Viscoelastic properties of Pseudomonas aeruginosa variant biofilms. Sci Rep 2018; 8:9691. [PMID: 29946126 PMCID: PMC6018706 DOI: 10.1038/s41598-018-28009-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 06/05/2018] [Indexed: 01/11/2023] Open
Abstract
Pseudomonas aeruginosa evolves during chronic pulmonary infections of cystic fibrosis (CF) patients, forming pathoadapted variants that are persistent. Mucoid and rugose small-colony variants (RSCVs) are typically isolated from sputum of CF patients. These variants overproduce exopolysaccharides in the biofilm extracellular polymeric substance (EPS). Currently, changes to the biophysical properties of RSCV and mucoid biofilms due to variations in EPS are not well understood. This knowledge may reveal how lung infections resist host clearance mechanisms. Here, we used mechanical indentation and shear rheometry to analyse the viscoelasticity of RSCV and mucoid colony-biofilms compared to their isogenic parent at 2-, 4-, and 6-d. While the viscoelasticity of parental colony-biofilms underwent fluctuating temporal changes, in contrast, RSCV and mucoid colony-biofilms showed a gradual progression to more elastic-solid behaviour. Theoretical indices of mucociliary and cough clearance predict that mature 6-d parental and RSCV biofilms may show reduced cough clearance from the lung, while early mucoid biofilms may show reduced clearance by both mechanisms. We propose that viscoelasticity be considered a virulence property of biofilms.
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Affiliation(s)
- Erin S Gloag
- Department of Microbial Infection and Immunity, Microbiology, The Ohio State University, Columbus, OH, 43210, USA
| | - Guy K German
- Department of Biomedical Engineering, Binghamton University, Binghamton, NY, 13902, USA
| | - Paul Stoodley
- Department of Microbial Infection and Immunity, Microbiology, The Ohio State University, Columbus, OH, 43210, USA. .,Department of Orthopedics, The Ohio State University, Columbus, OH, 43210, USA. .,National Centre for Advanced Tribology at Southampton, University of Southampton, Southampton, SO17 1BJ, UK.
| | - Daniel J Wozniak
- Department of Microbial Infection and Immunity, Microbiology, The Ohio State University, Columbus, OH, 43210, USA
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20
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Zachreson C, Yap X, Gloag ES, Shimoni R, Whitchurch CB, Toth M. Network patterns in exponentially growing two-dimensional biofilms. Phys Rev E 2017; 96:042401. [PMID: 29347525 DOI: 10.1103/physreve.96.042401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Indexed: 06/07/2023]
Abstract
Anisotropic collective patterns occur frequently in the morphogenesis of two-dimensional biofilms. These patterns are often attributed to growth regulation mechanisms and differentiation based on gradients of diffusing nutrients and signaling molecules. Here, we employ a model of bacterial growth dynamics to show that even in the absence of growth regulation or differentiation, confinement by an enclosing medium such as agar can itself lead to stable pattern formation over time scales that are employed in experiments. The underlying mechanism relies on path formation through physical deformation of the enclosing environment.
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Affiliation(s)
- Cameron Zachreson
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Xinhui Yap
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Erin S Gloag
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
- Center for Microbial Interface Biology, Ohio State University, 460 West 12th Avenue, Columbus, Ohio 43210, USA
| | - Raz Shimoni
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Cynthia B Whitchurch
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Milos Toth
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
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21
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Gloag ES, Elbadawi C, Zachreson CJ, Aharonovich I, Toth M, Charles IG, Turnbull L, Whitchurch CB. Micro-Patterned Surfaces That Exploit Stigmergy to Inhibit Biofilm Expansion. Front Microbiol 2017; 7:2157. [PMID: 28167929 PMCID: PMC5253354 DOI: 10.3389/fmicb.2016.02157] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 12/21/2016] [Indexed: 11/13/2022] Open
Abstract
Twitching motility is a mode of surface translocation that is mediated by the extension and retraction of type IV pili and which, depending on the conditions, enables migration of individual cells or can manifest as a complex multicellular collective behavior that leads to biofilm expansion. When twitching motility occurs at the interface of an abiotic surface and solidified nutrient media, it can lead to the emergence of extensive self-organized patterns of interconnected trails that form as a consequence of the actively migrating bacteria forging a furrow network in the substratum beneath the expanding biofilm. These furrows appear to direct bacterial movements much in the same way that roads and footpaths coordinate motor vehicle and human pedestrian traffic. Self-organizing systems such as these can be accounted for by the concept of stigmergy which describes self-organization that emerges through indirect communication via persistent signals within the environment. Many bacterial communities are able to actively migrate across solid and semi-solid surfaces through complex multicellular collective behaviors such as twitching motility and flagella-mediated swarming motility. Here, we have examined the potential of exploiting the stigmergic behavior of furrow-mediated trail following as a means of controlling bacterial biofilm expansion along abiotic surfaces. We found that incorporation of a series of parallel micro-fabricated furrows significantly impeded active biofilm expansion by Pseudomonas aeruginosa and Proteus vulgaris. We observed that in both cases bacterial movements tended to be directed along the furrows. We also observed that narrow furrows were most effective at disrupting biofilm expansion as they impeded the ability of cells to self-organize into multicellular assemblies required for escape from the furrows and migration into new territory. Our results suggest that the implementation of micro-fabricated furrows that exploit stigmergy may be a novel approach to impeding active biofilm expansion across abiotic surfaces such as those used in medical and industrial settings.
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Affiliation(s)
- Erin S Gloag
- The ithree institute, University of Technology Sydney Ultimo, NSW, Australia
| | - Christopher Elbadawi
- School of Mathematical and Physical Sciences, University of Technology Sydney Ultimo, NSW, Australia
| | - Cameron J Zachreson
- School of Mathematical and Physical Sciences, University of Technology Sydney Ultimo, NSW, Australia
| | - Igor Aharonovich
- School of Mathematical and Physical Sciences, University of Technology Sydney Ultimo, NSW, Australia
| | - Milos Toth
- School of Mathematical and Physical Sciences, University of Technology Sydney Ultimo, NSW, Australia
| | - Ian G Charles
- The ithree institute, University of Technology Sydney Ultimo, NSW, Australia
| | - Lynne Turnbull
- The ithree institute, University of Technology Sydney Ultimo, NSW, Australia
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22
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Gloag ES, Turnbull L, Javed MA, Wang H, Gee ML, Wade SA, Whitchurch CB. Stigmergy co-ordinates multicellular collective behaviours during Myxococcus xanthus surface migration. Sci Rep 2016; 6:26005. [PMID: 27225967 PMCID: PMC4881031 DOI: 10.1038/srep26005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 04/19/2016] [Indexed: 12/29/2022] Open
Abstract
Surface translocation by the soil bacterium Myxococcus xanthus is a complex multicellular phenomenon that entails two motility systems. However, the mechanisms by which the activities of individual cells are coordinated to manifest this collective behaviour are currently unclear. Here we have developed a novel assay that enables detailed microscopic examination of M. xanthus motility at the interstitial interface between solidified nutrient medium and a glass coverslip. Under these conditions, M. xanthus motility is characterised by extensive micro-morphological patterning that is considerably more elaborate than occurs at an air-surface interface. We have found that during motility on solidified nutrient medium, M. xanthus forges an interconnected furrow network that is lined with an extracellular matrix comprised of exopolysaccharides, extracellular lipids, membrane vesicles and an unidentified slime. Our observations have revealed that M. xanthus motility on solidified nutrient medium is a stigmergic phenomenon in which multi-cellular collective behaviours are co-ordinated through trail-following that is guided by physical furrows and extracellular matrix materials.
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Affiliation(s)
- Erin S Gloag
- The ithree institute, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Lynne Turnbull
- The ithree institute, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Muhammad A Javed
- Biotactical Engineering, IRIS, Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
| | - Huabin Wang
- School of Chemistry, University of Melbourne, Parkville, VIC 3010, Australia
| | - Michelle L Gee
- School of Chemistry, University of Melbourne, Parkville, VIC 3010, Australia
| | - Scott A Wade
- Biotactical Engineering, IRIS, Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, VIC 3122, Australia
| | - Cynthia B Whitchurch
- The ithree institute, University of Technology Sydney, Ultimo, NSW 2007, Australia
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23
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Turnbull L, Toyofuku M, Hynen AL, Kurosawa M, Pessi G, Petty NK, Osvath SR, Cárcamo-Oyarce G, Gloag ES, Shimoni R, Omasits U, Ito S, Yap X, Monahan LG, Cavaliere R, Ahrens CH, Charles IG, Nomura N, Eberl L, Whitchurch CB. Explosive cell lysis as a mechanism for the biogenesis of bacterial membrane vesicles and biofilms. Nat Commun 2016; 7:11220. [PMID: 27075392 PMCID: PMC4834629 DOI: 10.1038/ncomms11220] [Citation(s) in RCA: 372] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 03/02/2016] [Indexed: 02/07/2023] Open
Abstract
Many bacteria produce extracellular and surface-associated components such as membrane vesicles (MVs), extracellular DNA and moonlighting cytosolic proteins for which the biogenesis and export pathways are not fully understood. Here we show that the explosive cell lysis of a sub-population of cells accounts for the liberation of cytosolic content in Pseudomonas aeruginosa biofilms. Super-resolution microscopy reveals that explosive cell lysis also produces shattered membrane fragments that rapidly form MVs. A prophage endolysin encoded within the R- and F-pyocin gene cluster is essential for explosive cell lysis. Endolysin-deficient mutants are defective in MV production and biofilm development, consistent with a crucial role in the biogenesis of MVs and liberation of extracellular DNA and other biofilm matrix components. Our findings reveal that explosive cell lysis, mediated through the activity of a cryptic prophage endolysin, acts as a mechanism for the production of bacterial MVs.
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Affiliation(s)
- Lynne Turnbull
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Masanori Toyofuku
- Department of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.,Department of Plant and Microbial Biology, University of Zurich, Zürich 8008, Switzerland
| | - Amelia L Hynen
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Masaharu Kurosawa
- Department of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan
| | - Gabriella Pessi
- Department of Plant and Microbial Biology, University of Zurich, Zürich 8008, Switzerland
| | - Nicola K Petty
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Sarah R Osvath
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Gerardo Cárcamo-Oyarce
- Department of Plant and Microbial Biology, University of Zurich, Zürich 8008, Switzerland
| | - Erin S Gloag
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Raz Shimoni
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Ulrich Omasits
- Department of Biology, Institute of Molecular Systems Biology, ETH Zurich, Zürich 8093, Switzerland
| | - Satoshi Ito
- Department of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan
| | - Xinhui Yap
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Leigh G Monahan
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Rosalia Cavaliere
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Christian H Ahrens
- Agroscope, Institute for Plant Production Sciences, Research Group Molecular Diagnostics, Genomics and Bioinformatics, &Swiss Institute of Bioinformatics (SIB), Wädenswil 8820, Switzerland
| | - Ian G Charles
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | - Nobuhiko Nomura
- Department of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan
| | - Leo Eberl
- Department of Plant and Microbial Biology, University of Zurich, Zürich 8008, Switzerland
| | - Cynthia B Whitchurch
- The ithree institute, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
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24
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Gloag ES, Turnbull L, Whitchurch CB. Bacterial stigmergy: an organising principle of multicellular collective behaviours of bacteria. Scientifica (Cairo) 2015; 2015:387342. [PMID: 25653882 PMCID: PMC4306409 DOI: 10.1155/2015/387342] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 12/17/2014] [Accepted: 12/17/2014] [Indexed: 06/04/2023]
Abstract
The self-organisation of collective behaviours often manifests as dramatic patterns of emergent large-scale order. This is true for relatively "simple" entities such as microbial communities and robot "swarms," through to more complex self-organised systems such as those displayed by social insects, migrating herds, and many human activities. The principle of stigmergy describes those self-organised phenomena that emerge as a consequence of indirect communication between individuals of the group through the generation of persistent cues in the environment. Interestingly, despite numerous examples of multicellular behaviours of bacteria, the principle of stigmergy has yet to become an accepted theoretical framework that describes how bacterial collectives self-organise. Here we review some examples of multicellular bacterial behaviours in the context of stigmergy with the aim of bringing this powerful and elegant self-organisation principle to the attention of the microbial research community.
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Affiliation(s)
- Erin S. Gloag
- The ithree Institute, University of Technology Sydney, P.O. Box 123, Broadway, Sydney, NSW 2007, Australia
| | - Lynne Turnbull
- The ithree Institute, University of Technology Sydney, P.O. Box 123, Broadway, Sydney, NSW 2007, Australia
| | - Cynthia B. Whitchurch
- The ithree Institute, University of Technology Sydney, P.O. Box 123, Broadway, Sydney, NSW 2007, Australia
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25
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Gloag ES, Javed MA, Wang H, Gee ML, Wade SA, Turnbull L, Whitchurch CB. Stigmergy: A key driver of self-organization in bacterial biofilms. Commun Integr Biol 2013; 6:e27331. [PMID: 24753789 PMCID: PMC3984292 DOI: 10.4161/cib.27331] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Accepted: 11/25/2013] [Indexed: 11/19/2022] Open
Abstract
Bacterial biofilms are complex multicellular communities that are often associated with the emergence of large-scale patterns across the biofilm. How bacteria self-organize to form these structured communities is an area of active research. We have recently determined that the emergence of an intricate network of trails that forms during the twitching motility mediated expansion of Pseudomonas aeruginosa biofilms is attributed to an interconnected furrow system that is forged in the solidified nutrient media by aggregates of cells as they migrate across the media surface. This network acts as a means for self-organization of collective behavior during biofilm expansion as the cells following these vanguard aggregates were preferentially confined within the furrow network resulting in the formation of an intricate network of trails of cells. Here we further explore the process by which the intricate network of trails emerges. We have determined that the formation of the intricate network of furrows is associated with significant remodeling of the sub-stratum underlying the biofilm. The concept of stigmergy has been used to describe a variety of self-organization processes observed in higher organisms and abiotic systems that involve indirect communication via persistent cues in the environment left by individuals that influence the behavior of other individuals of the group at a later point in time. We propose that the concept of stigmergy can also be applied to describe self-organization of bacterial biofilms and can be included in the repertoire of systems used by bacteria to coordinate complex multicellular behaviors.
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Affiliation(s)
- Erin S Gloag
- The ithree institute; University of Technology Sydney; Ultimo, NSW Australia
| | - Muhammad A Javed
- Faculty of Engineering and Industrial Sciences; Biotactical Engineering; IRIS; Swinburne University of Technology; Hawthorn, VIC Australia
| | - Huabin Wang
- School of Chemistry; University of Melbourne; Parkville, VIC Australia
| | - Michelle L Gee
- School of Chemistry; University of Melbourne; Parkville, VIC Australia
| | - Scott A Wade
- Faculty of Engineering and Industrial Sciences; Biotactical Engineering; IRIS; Swinburne University of Technology; Hawthorn, VIC Australia
| | - Lynne Turnbull
- The ithree institute; University of Technology Sydney; Ultimo, NSW Australia
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