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Motta EVS, de Jong TK, Gage A, Edwards JA, Moran NA. Glyphosate effects on growth and biofilm formation in bee gut symbionts and diverse associated bacteria. Appl Environ Microbiol 2024; 90:e0051524. [PMID: 39012136 PMCID: PMC11337805 DOI: 10.1128/aem.00515-24] [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: 03/20/2024] [Accepted: 06/22/2024] [Indexed: 07/17/2024] Open
Abstract
Biofilm formation is a common adaptation enabling bacteria to thrive in various environments and withstand external pressures. In the context of host-microbe interactions, biofilms play vital roles in establishing microbiomes associated with animals and plants and are used by opportunistic microbes to facilitate survival within hosts. Investigating biofilm dynamics, composition, and responses to environmental stressors is crucial for understanding microbial community assembly and biofilm regulation in health and disease. In this study, we explore in vivo colonization and in vitro biofilm formation abilities of core members of the honey bee (Apis mellifera) gut microbiota. Additionally, we assess the impact of glyphosate, a widely used herbicide with antimicrobial properties, and a glyphosate-based herbicide formulation on growth and biofilm formation in bee gut symbionts as well as in other biofilm-forming bacteria associated with diverse animals and plants. Our results demonstrate that several strains of core bee gut bacterial species can colonize the bee gut, which probably depends on their ability to form biofilms. Furthermore, glyphosate exposure elicits variable effects on bacterial growth and biofilm formation. In some instances, the effects correlate with the bacteria's ability to encode a susceptible or tolerant version of the enzyme inhibited by glyphosate in the shikimate pathway. However, in other instances, no such correlation is observed. Testing the herbicide formulation further complicates comparisons, as results often diverge from glyphosate exposure alone, suggesting that co-formulants influence bacterial growth and biofilm formation. These findings highlight the nuanced impacts of environmental stressors on microbial biofilms, with both ecological and host health-related implications. IMPORTANCE Biofilms are essential for microbial communities to establish and thrive in diverse environments. In the honey bee gut, the core microbiota member Snodgrassella alvi forms biofilms, potentially aiding the establishment of other members and promoting interactions with the host. In this study, we show that specific strains of other core members, including Bifidobacterium, Bombilactobacillus, Gilliamella, and Lactobacillus, also form biofilms in vitro. We then examine the impact of glyphosate, a widely used herbicide that can disrupt the bee microbiota, on bacterial growth and biofilm formation. Our findings demonstrate the diverse effects of glyphosate on biofilm formation, ranging from inhibition to enhancement, reflecting observations in other beneficial or pathogenic bacteria associated with animals and plants. Thus, glyphosate exposure may influence bacterial growth and biofilm formation, potentially shaping microbial establishment on host surfaces and impacting health outcomes.
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Affiliation(s)
- Erick V. S. Motta
- Department of Integrative Biology, The University of Texas at Austin, Austin, Texas, USA
- Department of Entomology, Texas A&M University, College Station, Texas, USA
| | - Tyler K. de Jong
- Department of Integrative Biology, The University of Texas at Austin, Austin, Texas, USA
| | - Alejandra Gage
- Department of Integrative Biology, The University of Texas at Austin, Austin, Texas, USA
| | - Joseph A. Edwards
- Department of Integrative Biology, The University of Texas at Austin, Austin, Texas, USA
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, Texas, USA
| | - Nancy A. Moran
- Department of Integrative Biology, The University of Texas at Austin, Austin, Texas, USA
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2
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Chen G, Fanouraki G, Anandhi Rangarajan A, Winkelman BT, Winkelman JT, Waters CM, Mukherjee S. Combinatorial control of Pseudomonas aeruginosa biofilm development by quorum-sensing and nutrient-sensing regulators. mSystems 2024:e0037224. [PMID: 39140783 DOI: 10.1128/msystems.00372-24] [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: 03/13/2024] [Accepted: 06/23/2024] [Indexed: 08/15/2024] Open
Abstract
The human pathogen Pseudomonas aeruginosa, a leading cause of hospital-acquired infections, inhabits and forms sessile antibiotic-resistant communities called biofilms in a wide range of biotic and abiotic environments. In this study, we examined how two global sensory signaling pathways-the RhlR quorum-sensing system and the CbrA/CbrB nutritional adaptation system-intersect to control biofilm development. Previous work has shown that individually these two systems repress biofilm formation. Here, we used biofilm analyses, RNA-seq, and reporter assays to explore the combined effect of information flow through RhlR and CbrA on biofilm development. We find that the ΔrhlRΔcbrA double mutant exhibits a biofilm morphology and an associated transcriptional response distinct from wildtype and the parent ΔrhlR and ΔcbrA mutants indicating codominance of each signaling pathway. The ΔrhlRΔcbrA mutant gains suppressor mutations that allow biofilm expansion; these mutations map to the crc gene resulting in loss of function of the carbon catabolite repression protein Crc. Furthermore, the combined absence of RhlR and CbrA leads to a drastic reduction in the abundance of the Crc antagonist small RNA CrcZ. Thus, CrcZ acts as the molecular convergence point for quorum- and nutrient-sensing cues. We find that in the absence of antagonism by CrcZ, Crc promotes the expression of biofilm matrix components-Pel exopolysaccharide, and CupB and CupC fimbriae. Therefore, this study uncovers a regulatory link between nutritional adaption and quorum sensing with potential implications for anti-biofilm targeting strategies.IMPORTANCEBacteria often form multicellular communities encased in an extracytoplasmic matrix called biofilms. Biofilm development is controlled by various environmental stimuli that are decoded and converted into appropriate cellular responses. To understand how information from two distinct stimuli is integrated, we used biofilm formation in the human pathogen Pseudomonas aeruginosa as a model and studied the intersection of two global sensory signaling pathways-quorum sensing and nutritional adaptation. Global transcriptomics on biofilm cells and reporter assays suggest parallel regulation of biofilms by each pathway that converges on the abundance of a small RNA antagonist of the carbon catabolite repression protein, Crc. We find a new role of Crc as it modulates the expression of biofilm matrix components in response to the environment. These results expand our understanding of the genetic regulatory strategies that allow P. aeruginosa to successfully develop biofilm communities.
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Affiliation(s)
- Gong Chen
- Department of Molecular Genetics & Cell Biology, The University of Chicago, Chicago, Illinois, USA
| | - Georgia Fanouraki
- Department of Molecular Genetics & Cell Biology, The University of Chicago, Chicago, Illinois, USA
| | | | | | - Jared T Winkelman
- Department of Molecular Genetics & Cell Biology, The University of Chicago, Chicago, Illinois, USA
| | - Christopher M Waters
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | - Sampriti Mukherjee
- Department of Molecular Genetics & Cell Biology, The University of Chicago, Chicago, Illinois, USA
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3
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Liu MY, Liu X, Wang CY, Wan QQ, Tian YF, Liu SL, Pang DW, Wang ZG. Inhalable Polymeric Microparticles for Phage and Photothermal Synergistic Therapy of Methicillin-Resistant Staphylococcus aureus Pneumonia. NANO LETTERS 2024; 24:8752-8762. [PMID: 38953881 DOI: 10.1021/acs.nanolett.4c02318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
Acute methicillin-resistant Staphylococcus aureus (MRSA) pneumonia is a common and serious lung infection with high morbidity and mortality rates. Due to the increasing antibiotic resistance, toxicity, and pathogenicity of MRSA, there is an urgent need to explore effective antibacterial strategies. In this study, we developed a dry powder inhalable formulation which is composed of porous microspheres prepared from poly(lactic-co-glycolic acid) (PLGA), internally loaded with indocyanine green (ICG)-modified, heat-resistant phages that we screened for their high efficacy against MRSA. This formulation can deliver therapeutic doses of ICG-modified active phages to the deep lung tissue infection sites, avoiding rapid clearance by alveolar macrophages. Combined with the synergistic treatment of phage therapy and photothermal therapy, the formulation demonstrates potent bactericidal effects in acute MRSA pneumonia. With its long-term stability at room temperature and inhalable characteristics, this formulation has the potential to be a promising drug for the clinical treatment of MRSA pneumonia.
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Affiliation(s)
- Meng-Yao Liu
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Centre for New Organic Matter, School of Medicine and College of Chemistry, Frontiers Science Center for Cell Responses, Nankai University, Tianjin, 300071, People's Republic of China
| | - Xing Liu
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Centre for New Organic Matter, School of Medicine and College of Chemistry, Frontiers Science Center for Cell Responses, Nankai University, Tianjin, 300071, People's Republic of China
| | - Chun-Yu Wang
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Centre for New Organic Matter, School of Medicine and College of Chemistry, Frontiers Science Center for Cell Responses, Nankai University, Tianjin, 300071, People's Republic of China
| | - Qian-Qian Wan
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Centre for New Organic Matter, School of Medicine and College of Chemistry, Frontiers Science Center for Cell Responses, Nankai University, Tianjin, 300071, People's Republic of China
| | - Yi-Fan Tian
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Centre for New Organic Matter, School of Medicine and College of Chemistry, Frontiers Science Center for Cell Responses, Nankai University, Tianjin, 300071, People's Republic of China
| | - Shu-Lin Liu
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Centre for New Organic Matter, School of Medicine and College of Chemistry, Frontiers Science Center for Cell Responses, Nankai University, Tianjin, 300071, People's Republic of China
| | - Dai-Wen Pang
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Centre for New Organic Matter, School of Medicine and College of Chemistry, Frontiers Science Center for Cell Responses, Nankai University, Tianjin, 300071, People's Republic of China
| | - Zhi-Gang Wang
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Centre for New Organic Matter, School of Medicine and College of Chemistry, Frontiers Science Center for Cell Responses, Nankai University, Tianjin, 300071, People's Republic of China
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4
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Prentice JA, Kasivisweswaran S, van de Weerd R, Bridges AA. Biofilm dispersal patterns revealed using far-red fluorogenic probes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.15.603607. [PMID: 39071379 PMCID: PMC11275749 DOI: 10.1101/2024.07.15.603607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Bacteria frequently colonize niches by forming multicellular communities called biofilms. To explore new territories, cells exit biofilms through an active process called dispersal. Biofilm dispersal is essential for bacteria to spread between infection sites, yet how the process is executed at the single-cell level remains mysterious. Here, we characterize dispersal at unprecedented resolution for the global pathogen Vibrio cholerae. To do so, we first developed a far-red cell-labeling strategy that overcomes pitfalls of fluorescent protein-based approaches. We reveal that dispersal initiates at the biofilm periphery and ~25% of cells never disperse. We define novel micro-scale patterns that occur during dispersal, including biofilm compression and the formation of dynamic channels. These patterns are attenuated in mutants that reduce overall dispersal or that increase dispersal at the cost of homogenizing local mechanical properties. Collectively, our findings provide fundamental insights into the mechanisms of biofilm dispersal, advancing our understanding of how pathogens disseminate.
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Affiliation(s)
- Jojo A. Prentice
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh PA, USA
| | | | - Robert van de Weerd
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh PA, USA
- Ray and Stephanie Lane Computational Biology Department, Carnegie Mellon University, Pittsburgh PA, USA
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh PA, USA
| | - Andrew A. Bridges
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh PA, USA
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5
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Ramsey K, Britt M, Maramba J, Ushijima B, Moller E, Anishkin A, Häse C, Sukharev S. The dynamic hypoosmotic response of Vibrio cholerae relies on the mechanosensitive channel MscS. iScience 2024; 27:110001. [PMID: 38868203 PMCID: PMC11167432 DOI: 10.1016/j.isci.2024.110001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 03/04/2024] [Accepted: 05/14/2024] [Indexed: 06/14/2024] Open
Abstract
Vibrio cholerae adapts to osmotic down-shifts by releasing metabolites through two mechanosensitive (MS) channels, low-threshold MscS and high-threshold MscL. To investigate each channel's contribution to the osmotic response, we generated ΔmscS, ΔmscL, and double ΔmscL ΔmscS mutants in V. cholerae O395. We characterized their tension-dependent activation in patch-clamp, and the millisecond-scale osmolyte release kinetics using a stopped-flow light scattering technique. We additionally generated numerical models describing osmolyte and water fluxes. We illustrate the sequence of events and define the parameters that characterize discrete phases of the osmotic response. Survival is correlated to the extent of cell swelling, the rate of osmolyte release, and the completeness of post-shock membrane resealing. Not only do the two channels interact functionally, but there is also an up-regulation of MscS in the ΔmscL strain, suggesting transcriptional crosstalk. The data reveal the role of MscS in the termination of the osmotic permeability response in V. cholerae.
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Affiliation(s)
- Kristen Ramsey
- Department of Biology, University of Maryland, College Park, MD, USA
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, CT, USA
| | - Madolyn Britt
- Department of Biology, University of Maryland, College Park, MD, USA
- Biophysics Graduate Program, University of Maryland, College Park, MD, USA
| | - Joseph Maramba
- Department of Biology, University of Maryland, College Park, MD, USA
| | - Blake Ushijima
- Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, NC, USA
| | - Elissa Moller
- Department of Biology, University of Maryland, College Park, MD, USA
- Biophysics Graduate Program, University of Maryland, College Park, MD, USA
| | - Andriy Anishkin
- Department of Biology, University of Maryland, College Park, MD, USA
| | - Claudia Häse
- Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR, USA
| | - Sergei Sukharev
- Department of Biology, University of Maryland, College Park, MD, USA
- Biophysics Graduate Program, University of Maryland, College Park, MD, USA
- Institute for Physical Science and Technology, University of Maryland, College Park, MD, USA
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6
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Rashtchi P, Sudmalis D, van der Linden E, Abee T, Habibi M. Colonization and spreading dynamics of Lactiplantibacillus plantarum spoilage isolates on wet surfaces. Microbiol Res 2024; 283:127674. [PMID: 38461572 DOI: 10.1016/j.micres.2024.127674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 02/20/2024] [Accepted: 03/03/2024] [Indexed: 03/12/2024]
Abstract
The role of lactic acid bacteria, including Lactiplantibacillus plantarum, in food spoilage is well recognized, while the behavior of these non-motile bacteria on wet surfaces, such as those encountered in food processing environments has gained relatively little attention. Here, we observed a fast colony spreading of non-motile L. plantarum spoilage isolates on wet surfaces via passive sliding using solid BHI agar media as a model. We investigated the effect of physical properties of agar hydrogel substrate on the surface spreading of six L. plantarum food isolates FBR1-6 and a model strain WCFS1, using increasing concentrations of agar from 0.25 up to 1.5% (w/v). Our results revealed that L. plantarum strain FBR2 spreads significantly on low agar concentration plates compared to the other strains studied here (with a factor of 50-60 folds higher surface coverage), due to the formation of very soft biofilms with high water content that can float on the surface. The fast-spreading of FBR2 colonies is accompanied by an increased number of cells, elongated cell morphology, and a higher amount of extracellular components. Our finding highlights colonization dynamics and the spreading capacity of non-motile bacteria on surfaces that are relatively wet, thereby revealing an additional hitherto unnoticed parameter for non-motile bacteria that may contribute to contamination of foods by fast surface spreading of these bacteria in food processing environments.
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Affiliation(s)
- P Rashtchi
- Physics and Physical Chemistry of Foods, Wageningen University, Wageningen 6708WG, the Netherlands; Food Microbiology, Wageningen University, Wageningen 6708WG, the Netherlands
| | - D Sudmalis
- Environmental Technology, Wageningen University, Wageningen 6708WG, the Netherlands
| | - E van der Linden
- Physics and Physical Chemistry of Foods, Wageningen University, Wageningen 6708WG, the Netherlands
| | - T Abee
- Food Microbiology, Wageningen University, Wageningen 6708WG, the Netherlands
| | - Mehdi Habibi
- Physics and Physical Chemistry of Foods, Wageningen University, Wageningen 6708WG, the Netherlands.
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7
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Durairaj S, Sridhar D, Ströhle G, Li H, Chen A. Bactericidal Effect and Cytotoxicity of Graphene Oxide/Silver Nanocomposites. ACS APPLIED MATERIALS & INTERFACES 2024; 16:18300-18310. [PMID: 38574271 DOI: 10.1021/acsami.3c15798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/06/2024]
Abstract
To tackle the proliferation of pathogenic microorganisms without relying on antibiotics, innovative materials boasting antimicrobial properties have been engineered. This study focuses on the development of graphene oxide/silver (GO/Ag) nanocomposites, derived from partially reduced graphene oxide adorned with silver nanoparticles. Various nanocomposites with different amounts of silver (GO/Ag-1, GO/Ag-2, GO/Ag-3, and GO/Ag-4) were synthesized, and their antibacterial efficacy was systematically studied. The silver nanoparticles were uniformly deposited on the partially reduced graphene oxide surface, exhibiting spherical morphologies with an average size of 25 nm. The nanocomposites displayed potent antibacterial properties against both gram-positive bacteria (S. aureus and B. subtilis) and gram-negative bacteria (E. coli and S. enterica) as confirmed by minimum inhibition concentration (MIC) studies and time-dependent experiments. The optimal MIC for Gram-positive bacteria was 62.5 μg/mL and for Gram-negative bacteria was 125 μg/mL for the GO/Ag nanocomposites. Bacterial cells that encountered the nanocomposite films exhibited significantly greater inhibitory effects compared to those exposed to conventional antibacterial materials. Furthermore, the cytotoxicity of these nanocomposites was assessed using human epithelial cells (HEC), revealing that GO/Ag-1 and GO/Ag-2 exhibited lower toxicity levels toward HEC and remained compatible even at higher dilution rates. This study underscores the potential of GO/Ag-based nanocomposites as versatile materials for antibacterial applications, particularly as biocompatible wound dressings, offering promising prospects for wound healing and infection control.
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Affiliation(s)
- Sharmila Durairaj
- Electrochemical Technology Centre, Department of Chemistry, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
| | - Deepak Sridhar
- Zentek Ltd., 24 Corporate Court, Guelph, Ontario N1G 5G5, Canada
| | - Gisela Ströhle
- School of Engineering, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
| | - Huiyan Li
- School of Engineering, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
| | - Aicheng Chen
- Electrochemical Technology Centre, Department of Chemistry, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
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8
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Siri M, Mangiarotti A, Vázquez-Dávila M, Bidan CM. Curli Amyloid Fibers in Escherichia coli Biofilms: The Influence of Water Availability on their Structure and Functional Properties. Macromol Biosci 2024; 24:e2300234. [PMID: 37776075 DOI: 10.1002/mabi.202300234] [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: 05/24/2023] [Revised: 09/22/2023] [Indexed: 10/01/2023]
Abstract
Escherichia coli biofilms consist of bacteria embedded in a self-produced matrix mainly made of protein fibers and polysaccharides. The curli amyloid fibers found in the biofilm matrix are promising versatile building blocks to design sustainable bio-sourced materials. To exploit this potential, it is crucial to understand i) how environmental cues during biofilm growth influence the molecular structure of these amyloid fibers, and ii) how this translates at higher length scales. To explore these questions, the effect of water availability during biofilm growth on the conformation and functions of curli is studied. Microscopy and spectroscopy are used to characterize the amyloid fibers purified from biofilms grown on nutritive substrates with different water contents, and micro-indentation to measure the rigidity of the respective biofilms. The purified curli amyloid fibers present differences in the yield, structure, and functional properties upon biofilm growth conditions. Fiber packing and β-sheets content correlate with their hydrophobicity and chemical stability, and with the rigidity of the biofilms. This study highlights how E. coli biofilm growth conditions impact curli structure and functions contributing to macroscopic materials properties. These fundamental findings infer an alternative strategy to tune curli structure, which will ultimately benefit engineering hierarchical and functional curli-based materials.
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Affiliation(s)
- Macarena Siri
- Max Planck Institute of Colloids and Interfaces, Department of Biomaterials, 14476, Potsdam, Germany
| | - Agustín Mangiarotti
- Max Planck Institute of Colloids and Interfaces, Department of Sustainable and Bio-inspired Materials, 14476, Potsdam, Germany
| | - Mónica Vázquez-Dávila
- Max Planck Institute of Colloids and Interfaces, Department of Biomaterials, 14476, Potsdam, Germany
| | - Cécile M Bidan
- Max Planck Institute of Colloids and Interfaces, Department of Biomaterials, 14476, Potsdam, Germany
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9
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Kochanowski JA, Carroll B, Asp ME, Kaputa EC, Patteson AE. Bacteria Colonies Modify Their Shear and Compressive Mechanical Properties in Response to Different Growth Substrates. ACS APPLIED BIO MATERIALS 2024. [PMID: 38193703 DOI: 10.1021/acsabm.3c00907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Abstract
Bacteria build multicellular communities termed biofilms, which are often encased in a self-secreted extracellular matrix that gives the community mechanical strength and protection against harsh chemicals. How bacteria assemble distinct multicellular structures in response to different environmental conditions remains incompletely understood. Here, we investigated the connection between bacteria colony mechanics and the colony growth substrate by measuring the oscillatory shear and compressive rheology of bacteria colonies grown on agar substrates. We found that bacteria colonies modify their own mechanical properties in response to shear and uniaxial compression in a manner that depends on the concentration of agar in their growth substrate. These findings highlight that mechanical interactions between bacteria and their microenvironments are an important element in bacteria colony development, which can aid in developing strategies to disrupt or reduce biofilm growth.
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Affiliation(s)
- Jakub A Kochanowski
- Physics Department and BioInspired Institute, Syracuse University, Syracuse, New York 13210, United States
| | - Bobby Carroll
- Physics Department and BioInspired Institute, Syracuse University, Syracuse, New York 13210, United States
| | - Merrill E Asp
- Physics Department and BioInspired Institute, Syracuse University, Syracuse, New York 13210, United States
| | - Emma C Kaputa
- Physics Department and BioInspired Institute, Syracuse University, Syracuse, New York 13210, United States
| | - Alison E Patteson
- Physics Department and BioInspired Institute, Syracuse University, Syracuse, New York 13210, United States
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10
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Wu J, Li X, Kong R, Wang J, Wang X. Analysis of biofilm expansion rate of Bacillus subtilis (MTC871) on agar substrates with different stiffness. Can J Microbiol 2023; 69:479-487. [PMID: 37379574 DOI: 10.1139/cjm-2022-0259] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/30/2023]
Abstract
The surface morphology of mature biofilms is heterogeneous and can be divided into concentric rings wrinkles (I), labyrinthine networks wrinkles (II), radial ridges wrinkles (III), and branches wrinkles (IV), according to surface wrinkle structure and distribution characteristics. Due to the wrinkle structures, channels are formed between the biofilm and substrate and transport nutrients, water, metabolic products, etc. We find that expansion rate variations of biofilms growing on substrates with high and low agar concentrations (1.5, 2.0, 2.5 wt.%) are not in the same phase. In the first 3 days' growth, the interaction stress between biofilm and each agar substrate increases, which makes the biofilm expansion rate decreases before wrinkle pattern IV (branches) comes up. After 3 days, in the later growth stage after wrinkle pattern IV appears, the biofilm has larger expansion rate growing on 2.0 wt.% agar concentration, which has the larger wrinkle distance in wrinkle pattern IV reducing energy consumption. Our study shows that the stiff substrate does not always inhibit the biofilm expansion, although it does in the earlier stage; after that, mature biofilms acquire larger expansion rate by adjusting the growth mode through the wrinkle evolution even in nutrient extremely depletion.
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Affiliation(s)
- Jin Wu
- School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Xianyong Li
- School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Rui Kong
- School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Jiankun Wang
- School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Xiaoling Wang
- School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083, China
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
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11
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Liu Y, Wu W, Feng S, Chen Y, Wu X, Zhang Q, Wu S. Dynamic response of the cell traction force to osmotic shock. MICROSYSTEMS & NANOENGINEERING 2023; 9:131. [PMID: 37854722 PMCID: PMC10579240 DOI: 10.1038/s41378-023-00603-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 08/07/2023] [Accepted: 09/14/2023] [Indexed: 10/20/2023]
Abstract
Osmotic pressure is vital to many physiological activities, such as cell proliferation, wound healing and disease treatment. However, how cells interact with the extracellular matrix (ECM) when subjected to osmotic shock remains unclear. Here, we visualize the mechanical interactions between cells and the ECM during osmotic shock by quantifying the dynamic evolution of the cell traction force. We show that both hypertonic and hypotonic shocks induce continuous and large changes in cell traction force. Moreover, the traction force varies with cell volume: the traction force increases as cells shrink and decreases as cells swell. However, the direction of the traction force is independent of cell volume changes and is always toward the center of the cell-substrate interface. Furthermore, we reveal a mechanical mechanism in which the change in cortical tension caused by osmotic shock leads to the variation in traction force, which suggests a simple method for measuring changes in cell cortical tension. These findings provide new insights into the mechanical force response of cells to the external environment and may provide a deeper understanding of how the ECM regulates cell structure and function. Traction force exerted by cells under hypertonic and hypotonic shocks. Scale bar, 200 Pa. Color bar, Pa. The black arrows represent the tangential traction forces.
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Affiliation(s)
- Yongman Liu
- School of Biomedical Engineering, Anhui Medical University, 230032 Hefei, China
- CAS Key Laboratory of Mechanical Behavior and Design of Material, Department of Modern Mechanics, CAS Center for Excellence in Complex System Mechanics, University of Science and Technology of China, 230026 Hefei, China
| | - Wenjie Wu
- CAS Key Laboratory of Mechanical Behavior and Design of Material, Department of Modern Mechanics, CAS Center for Excellence in Complex System Mechanics, University of Science and Technology of China, 230026 Hefei, China
| | - Shuo Feng
- CAS Key Laboratory of Mechanical Behavior and Design of Material, Department of Modern Mechanics, CAS Center for Excellence in Complex System Mechanics, University of Science and Technology of China, 230026 Hefei, China
| | - Ye Chen
- CAS Key Laboratory of Mechanical Behavior and Design of Material, Department of Modern Mechanics, CAS Center for Excellence in Complex System Mechanics, University of Science and Technology of China, 230026 Hefei, China
| | - Xiaoping Wu
- CAS Key Laboratory of Mechanical Behavior and Design of Material, Department of Modern Mechanics, CAS Center for Excellence in Complex System Mechanics, University of Science and Technology of China, 230026 Hefei, China
| | - Qingchuan Zhang
- CAS Key Laboratory of Mechanical Behavior and Design of Material, Department of Modern Mechanics, CAS Center for Excellence in Complex System Mechanics, University of Science and Technology of China, 230026 Hefei, China
| | - Shangquan Wu
- CAS Key Laboratory of Mechanical Behavior and Design of Material, Department of Modern Mechanics, CAS Center for Excellence in Complex System Mechanics, University of Science and Technology of China, 230026 Hefei, China
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12
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Charlton SG, Bible AN, Secchi E, Morrell‐Falvey JL, Retterer ST, Curtis TP, Chen J, Jana S. Microstructural and Rheological Transitions in Bacterial Biofilms. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2207373. [PMID: 37522628 PMCID: PMC10520682 DOI: 10.1002/advs.202207373] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 06/20/2023] [Indexed: 08/01/2023]
Abstract
Biofilms are aggregated bacterial communities structured within an extracellular matrix (ECM). ECM controls biofilm architecture and confers mechanical resistance against shear forces. From a physical perspective, biofilms can be described as colloidal gels, where bacterial cells are analogous to colloidal particles distributed in the polymeric ECM. However, the influence of the ECM in altering the cellular packing fraction (ϕ) and the resulting viscoelastic behavior of biofilm remains unexplored. Using biofilms of Pantoea sp. (WT) and its mutant (ΔUDP), the correlation between biofilm structure and its viscoelastic response is investigated. Experiments show that the reduction of exopolysaccharide production in ΔUDP biofilms corresponds with a seven-fold increase in ϕ, resulting in a colloidal glass-like structure. Consequently, the rheological signatures become altered, with the WT behaving like a weak gel, whilst the ΔUDP displayed a glass-like rheological signature. By co-culturing the two strains, biofilm ϕ is modulated which allows us to explore the structural changes and capture a change in viscoelastic response from a weak to a strong gel, and to a colloidal glass-like state. The results reveal the role of exopolysaccharide in mediating a structural transition in biofilms and demonstrate a correlation between biofilm structure and viscoelastic response.
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Affiliation(s)
- Samuel G.V. Charlton
- Department of Civil, Environmental and Geomatic EngineeringInstitute of Environmental EngineeringETH ZurichZurich8049Switzerland
- School of EngineeringNewcastle UniversityNewcastle Upon TyneNE1 7RUUK
| | - Amber N. Bible
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN37830USA
| | - Eleonora Secchi
- Department of Civil, Environmental and Geomatic EngineeringInstitute of Environmental EngineeringETH ZurichZurich8049Switzerland
| | | | - Scott T. Retterer
- Biosciences DivisionOak Ridge National LaboratoryOak RidgeTN37830USA
- Center for Nanophase Material SciencesOak Ridge National LaboratoryOak RidgeTN37830USA
| | - Thomas P. Curtis
- School of EngineeringNewcastle UniversityNewcastle Upon TyneNE1 7RUUK
| | - Jinju Chen
- School of EngineeringNewcastle UniversityNewcastle Upon TyneNE1 7RUUK
| | - Saikat Jana
- School of EngineeringNewcastle UniversityNewcastle Upon TyneNE1 7RUUK
- School of EngineeringUlster UniversityBelfastBT15 1APUK
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13
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Zhong ZP, Vik D, Rapp JZ, Zablocki O, Maughan H, Temperton B, Deming JW, Sullivan MB. Lower viral evolutionary pressure under stable versus fluctuating conditions in subzero Arctic brines. MICROBIOME 2023; 11:174. [PMID: 37550784 PMCID: PMC10405475 DOI: 10.1186/s40168-023-01619-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 07/12/2023] [Indexed: 08/09/2023]
Abstract
BACKGROUND Climate change threatens Earth's ice-based ecosystems which currently offer archives and eco-evolutionary experiments in the extreme. Arctic cryopeg brine (marine-derived, within permafrost) and sea ice brine, similar in subzero temperature and high salinity but different in temporal stability, are inhabited by microbes adapted to these extreme conditions. However, little is known about their viruses (community composition, diversity, interaction with hosts, or evolution) or how they might respond to geologically stable cryopeg versus fluctuating sea ice conditions. RESULTS We used long- and short-read viromics and metatranscriptomics to study viruses in Arctic cryopeg brine, sea ice brine, and underlying seawater, recovering 11,088 vOTUs (~species-level taxonomic unit), a 4.4-fold increase of known viruses in these brines. More specifically, the long-read-powered viromes doubled the number of longer (≥25 kb) vOTUs generated and recovered more hypervariable regions by >5-fold compared to short-read viromes. Distribution assessment, by comparing to known viruses in public databases, supported that cryopeg brine viruses were of marine origin yet distinct from either sea ice brine or seawater viruses, while 94% of sea ice brine viruses were also present in seawater. A virus-encoded, ecologically important exopolysaccharide biosynthesis gene was identified, and many viruses (~half of metatranscriptome-inferred "active" vOTUs) were predicted as actively infecting the dominant microbial genera Marinobacter and Polaribacter in cryopeg and sea ice brines, respectively. Evolutionarily, microdiversity (intra-species genetic variations) analyses suggested that viruses within the stable cryopeg brine were under significantly lower evolutionary pressures than those in the fluctuating sea ice environment, while many sea ice brine virus-tail genes were under positive selection, indicating virus-host co-evolutionary arms races. CONCLUSIONS Our results confirmed the benefits of long-read-powered viromics in understanding the environmental virosphere through significantly improved genomic recovery, expanding viral discovery and the potential for biological inference. Evidence of viruses actively infecting the dominant microbes in subzero brines and modulating host metabolism underscored the potential impact of viruses on these remote and underexplored extreme ecosystems. Microdiversity results shed light on different strategies viruses use to evolve and adapt when extreme conditions are stable versus fluctuating. Together, these findings verify the value of long-read-powered viromics and provide foundational data on viral evolution and virus-microbe interactions in Earth's destabilized and rapidly disappearing cryosphere. Video Abstract.
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Affiliation(s)
- Zhi-Ping Zhong
- Byrd Polar and Climate Research Center, Ohio State University, Columbus, OH, USA
- Department of Microbiology, Ohio State University, Columbus, OH, USA
- Center of Microbiome Science, Ohio State University, Columbus, OH, USA
| | - Dean Vik
- Department of Microbiology, Ohio State University, Columbus, OH, USA
- Center of Microbiome Science, Ohio State University, Columbus, OH, USA
| | - Josephine Z Rapp
- Department of Biology, Université Laval, Québec, QC, Canada
- Center for Northern Studies (CEN), Université Laval, Québec, QC, Canada
| | - Olivier Zablocki
- Department of Microbiology, Ohio State University, Columbus, OH, USA
- Center of Microbiome Science, Ohio State University, Columbus, OH, USA
| | | | - Ben Temperton
- School of Biosciences, University of Exeter, Exeter, Devon, UK
| | - Jody W Deming
- School of Oceanography and Astrobiology Program, University of Washington, Seattle, WA, USA.
| | - Matthew B Sullivan
- Byrd Polar and Climate Research Center, Ohio State University, Columbus, OH, USA.
- Department of Microbiology, Ohio State University, Columbus, OH, USA.
- Center of Microbiome Science, Ohio State University, Columbus, OH, USA.
- Department of Civil, Environmental and Geodetic Engineering, Ohio State University, Columbus, OH, USA.
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14
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Somasundar A, Qin B, Shim S, Bassler BL, Stone HA. Diffusiophoretic Particle Penetration into Bacterial Biofilms. ACS APPLIED MATERIALS & INTERFACES 2023; 15:33263-33272. [PMID: 37400078 PMCID: PMC10360038 DOI: 10.1021/acsami.3c03190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Accepted: 05/25/2023] [Indexed: 07/05/2023]
Abstract
Bacterial biofilms are communities of cells adhered to surfaces. These communities represent a predominant form of bacterial life on Earth. A defining feature of a biofilm is the three-dimensional extracellular polymer matrix that protects resident cells by acting as a mechanical barrier to the penetration of chemicals, such as antimicrobials. Beyond being recalcitrant to antibiotic treatment, biofilms are notoriously difficult to remove from surfaces. A promising, but relatively underexplored, approach to biofilm control is to disrupt the extracellular polymer matrix by enabling penetration of particles to increase the susceptibility of biofilms to antimicrobials. In this work, we investigate externally imposed chemical gradients as a mechanism to transport polystyrene particles into bacterial biofilms. We show that preconditioning the biofilm with a prewash step using deionized (DI) water is essential for altering the biofilm so it takes up the micro- and nanoparticles by the application of a further chemical gradient created by an electrolyte. Using different particles and chemicals, we document the transport behavior that leads to particle motion into the biofilm and its further reversal out of the biofilm. Our results demonstrate the importance of chemical gradients in disrupting the biofilm matrix and regulating particle transport in crowded macromolecular environments, and suggest potential applications of particle transport and delivery in other physiological systems.
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Affiliation(s)
- Ambika Somasundar
- Department
of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
- Princeton
Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey 08544, United States
| | - Boyang Qin
- Department
of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
- Department
of Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
| | - Suin Shim
- Department
of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Bonnie L. Bassler
- Department
of Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
- Howard
Hughes Medical Institute, Chevy
Chase, Maryland 20815, United States
| | - Howard A. Stone
- Department
of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
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15
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Asp ME, Thanh MTH, Dutta S, Comstock JA, Welch RD, Patteson AE. Mechanobiology as a tool for addressing the genotype-to-phenotype problem in microbiology. BIOPHYSICS REVIEWS 2023; 4:021304. [PMID: 38504926 PMCID: PMC10903382 DOI: 10.1063/5.0142121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 04/03/2023] [Indexed: 03/21/2024]
Abstract
The central hypothesis of the genotype-phenotype relationship is that the phenotype of a developing organism (i.e., its set of observable attributes) depends on its genome and the environment. However, as we learn more about the genetics and biochemistry of living systems, our understanding does not fully extend to the complex multiscale nature of how cells move, interact, and organize; this gap in understanding is referred to as the genotype-to-phenotype problem. The physics of soft matter sets the background on which living organisms evolved, and the cell environment is a strong determinant of cell phenotype. This inevitably leads to challenges as the full function of many genes, and the diversity of cellular behaviors cannot be assessed without wide screens of environmental conditions. Cellular mechanobiology is an emerging field that provides methodologies to understand how cells integrate chemical and physical environmental stress and signals, and how they are transduced to control cell function. Biofilm forming bacteria represent an attractive model because they are fast growing, genetically malleable and can display sophisticated self-organizing developmental behaviors similar to those found in higher organisms. Here, we propose mechanobiology as a new area of study in prokaryotic systems and describe its potential for unveiling new links between an organism's genome and phenome.
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16
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van den Berg L, Pronk M, van Loosdrecht MCM, de Kreuk MK. Density measurements of aerobic granular sludge. ENVIRONMENTAL TECHNOLOGY 2023; 44:1985-1995. [PMID: 34904922 DOI: 10.1080/09593330.2021.2017492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 12/05/2021] [Indexed: 05/25/2023]
Abstract
Granular sludge processes are frequently used in domestic and industrial wastewater treatment. The granule buoyant density and biomass density are important parameters for the design and operation of granular sludge reactors. Different methods to measure the granule density include the pycnometer method, the Percoll density gradient method, the dextran blue method, and the settling velocity method. In this study, a comparison was made between these four methods to measure granule density for granules from a full-scale granular sludge plant treating domestic sewage. The effect of salinity on granule density was assessed as well. Three out of the four evaluated methods yielded comparable results, with granule buoyant densities between 1025.7 and 1028.1 kg/m3 and granule biomass densities between 71.1 and 71.5 g/L (based on volatile suspended solids (VSS)). The settling velocity method clearly underestimated the granule density, due to the complex relation between granule properties and settling velocity. The pycnometer method was the most precise method, but it was also quite susceptible to bias. The granule buoyant density increased proportionally with salinity, to 1049.2 kg/m3 at 36 g/L salinity. However, the granule biomass density, based on VSS, remained constant. This showed that the granule volume was not affected by salinity and that the buoyant density increase was the result of diffusion of salts into the granule pores. Overall, the granule density can be measured reliably with most methods, as long as the effect of salinity is considered. The results are discussed in light of operational aspects for full-scale granular sludge plants.
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Affiliation(s)
- Lenno van den Berg
- Department of Water Management, Delft University of Technology, Delft, the Netherlands
| | - Mario Pronk
- Department of Biotechnology, Delft University of Technology, Delft, the Netherlands
- Royal HaskoningDHV, Amersfoort, the Netherlands
| | | | - Merle K de Kreuk
- Department of Water Management, Delft University of Technology, Delft, the Netherlands
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17
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Zhou S, An W, Zhao K, Lin L, Yang S, Zhang Y, Xu M. Protection of electroactive biofilms against hypersaline shock by quorum sensing. WATER RESEARCH 2023; 233:119823. [PMID: 36871386 DOI: 10.1016/j.watres.2023.119823] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 01/22/2023] [Accepted: 02/26/2023] [Indexed: 06/18/2023]
Abstract
Quorum sensing (QS) is an ideal strategy for boosting the operating performance of electroactive biofilms (EABs), but its potential effects on the protection of electroactive biofilms against environmental shocks (e.g., hypersaline shock) have been rarely revealed. In this study, a QS signaling molecule, the N-(3-oxo-dodecanoyl)-L-homoserine lactone, was employed to promote the anti-shock property of the EABs against extreme saline shock. The maximum current density of the QS-regulated biofilm recovered to 0.17 mA/cm2 after 10% salinity exposure, which was much higher than those of its counterparts. The laser scanning confocal microscope confirmed a thicker and more compact biofilm with the presence of the QS signaling molecule. The extracellular polymeric substances (EPS) might play a crucial role in the anti-shocking behaviors, as the polysaccharides in EPS of QS-biofilm had doubled compared to the groups with acylase (the QS quencher). The microbial community analysis indicated that the QS molecule enriched the relative abundance of key species including Pseudomonas sp. and Geobacter sp., which were both beneficial to the stability and electroactivity of the biofilms. The functional genes related to the bacterial community were also up-regulated with the presence of the QS molecule. These results highlight the importance of QS effects in protecting electroactive biofilm under extreme environmental shock, which provides effective and feasible strategies for the future development of microbial electrochemical technologies.
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Affiliation(s)
- Shaofeng Zhou
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China; Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Wenwen An
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Kexin Zhao
- Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Lizhou Lin
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Shan Yang
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Yifeng Zhang
- Department of Environmental and Resource Engineering, Technical University of Denmark, Lyngby DK-2800, Denmark
| | - Meiying Xu
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China.
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18
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Platt TG. Community outcomes depend on cooperative biofilm structure. Proc Natl Acad Sci U S A 2023; 120:e2221624120. [PMID: 36730195 PMCID: PMC9963125 DOI: 10.1073/pnas.2221624120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Affiliation(s)
- Thomas G. Platt
- Division of Biology, Kansas State University, Manhattan, KS66506
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19
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Wang Y, Zhang X, Guan L, Jiang Z, Gao X, Hao S, Zhang X. A novel method to harvest microalgae biofilms by interfacial interaction. ALGAL RES 2023. [DOI: 10.1016/j.algal.2023.103000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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20
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Moreau A, Mukherjee S, Yan J. Mechanical Characterization and Single‐Cell Imaging of Bacterial Biofilms. Isr J Chem 2023. [DOI: 10.1002/ijch.202200075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Alexis Moreau
- Department of Molecular, Cellular and Developmental Biology, Quantitative Biology Institute Yale University 260 Whitney Ave. New Haven CT 06511 USA
| | - Sampriti Mukherjee
- Department of Molecular Genetics & Cell Biology University of Chicago 920 E. 58th Street, Suite 1106 Chicago IL 60637
| | - Jing Yan
- Department of Molecular, Cellular and Developmental Biology, Quantitative Biology Institute Yale University 260 Whitney Ave. New Haven CT 06511 USA
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21
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Bisht K, Luecke AR, Wakeman CA. Temperature-specific adaptations and genetic requirements in a biofilm formed by Pseudomonas aeruginosa. Front Microbiol 2023; 13:1032520. [PMID: 36687584 PMCID: PMC9853522 DOI: 10.3389/fmicb.2022.1032520] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 12/07/2022] [Indexed: 01/07/2023] Open
Abstract
Pseudomonas aeruginosa is a gram-negative opportunistic pathogen often associated with nosocomial infections that are made more severe by this bacterium's ability to form robust biofilms. A biofilm is a microbial community encompassing cells embedded within an extracellular polymeric substrate (EPS) matrix that is typically secreted by the encased microbial cells. Biofilm formation is influenced by several environmental cues, and temperature fluctuations are likely to be an important stimulus in the lifecycle of P. aeruginosa as it transitions between life in aquatic or soil environments to sites of infection in the human host. Previous work has demonstrated that human body temperature can induce a shift in the biofilm EPS relative to room temperature growth, resulting in an incorporation of a filamentous phage coat protein into the biofilm EPS. In this study, we sought to identify adaptations enabling biofilm formation at room temperature or temperatures mimicking the natural environment of P. aeruginosa (23°C and 30°C) relative to temperatures mimicking life in the human host (37°C and 40°C). We identified higher biofilm: biomass ratios at lower temperatures on certain substrates, which correlated with a higher relative abundance of apparent polysaccharide EPS content. However, the known genes for EPS polysaccharide production in P. aeruginosa PA14 did not appear to be specifically important for temperature-dependent biofilm adaptation, with the pelB gene appearing to be generally important and the algD gene being generally expendable in all conditions tested. Instead, we were able to identify two previously uncharacterized hypothetical proteins (PA14_50070 and PA14_67550) specifically required for biofilm formation at 23°C and/or 30°C relative to temperatures associated with the human host. These unstudied contributors to biofilm integrity may have been previously overlooked since most P. aeruginosa biofilm studies tend to use 37°C growth temperatures. Overall, our study demonstrates that temperature shifts can have dramatic impacts on biofilm structure and highlights the importance of studying environment-specific adaptations in biofilm physiology.
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Affiliation(s)
| | | | - Catherine A. Wakeman
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, United States
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22
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Tai JSB, Ferrell MJ, Yan J, Waters CM. New Insights into Vibrio cholerae Biofilms from Molecular Biophysics to Microbial Ecology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1404:17-39. [PMID: 36792869 PMCID: PMC10726288 DOI: 10.1007/978-3-031-22997-8_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
With the discovery that 48% of cholera infections in rural Bangladesh villages could be prevented by simple filtration of unpurified waters and the detection of Vibrio cholerae aggregates in stools from cholera patients it was realized V. cholerae biofilms had a central function in cholera pathogenesis. We are currently in the seventh cholera pandemic, caused by O1 serotypes of the El Tor biotypes strains, which initiated in 1961. It is estimated that V. cholerae annually causes millions of infections and over 100,000 deaths. Given the continued emergence of cholera in areas that lack access to clean water, such as Haiti after the 2010 earthquake or the ongoing Yemen civil war, increasing our understanding of cholera disease remains a worldwide public health priority. The surveillance and treatment of cholera is also affected as the world is impacted by the COVID-19 pandemic, raising significant concerns in Africa. In addition to the importance of biofilm formation in its life cycle, V. cholerae has become a key model system for understanding bacterial signal transduction networks that regulate biofilm formation and discovering fundamental principles about bacterial surface attachment and biofilm maturation. This chapter will highlight recent insights into V. cholerae biofilms including their structure, ecological role in environmental survival and infection, regulatory systems that control them, and biomechanical insights into the nature of V. cholerae biofilms.
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Affiliation(s)
- Jung-Shen B Tai
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Micah J Ferrell
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA
| | - Jing Yan
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Christopher M Waters
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA.
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23
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Evolutionary rescue of resistant mutants is governed by a balance between radial expansion and selection in compact populations. Nat Commun 2022; 13:7916. [PMID: 36564390 PMCID: PMC9789051 DOI: 10.1038/s41467-022-35484-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 12/06/2022] [Indexed: 12/24/2022] Open
Abstract
Mutation-mediated treatment resistance is one of the primary challenges for modern antibiotic and anti-cancer therapy. Yet, many resistance mutations have a substantial fitness cost and are subject to purifying selection. How emerging resistant lineages may escape purifying selection via subsequent compensatory mutations is still unclear due to the difficulty of tracking such evolutionary rescue dynamics in space and time. Here, we introduce a system of fluorescence-coupled synthetic mutations to show that the probability of evolutionary rescue, and the resulting long-term persistence of drug resistant mutant lineages, is dramatically increased in dense microbial populations. By tracking the entire evolutionary trajectory of thousands of resistant lineages in expanding yeast colonies we uncover an underlying quasi-stable equilibrium between the opposing forces of radial expansion and natural selection, a phenomenon we term inflation-selection balance. Tailored computational models and agent-based simulations corroborate the fundamental nature of the observed effects and demonstrate the potential impact on drug resistance evolution in cancer. The described phenomena should be considered when predicting multi-step evolutionary dynamics in any mechanically compact cellular population, including pathogenic microbial biofilms and solid tumors. The insights gained will be especially valuable for the quantitative understanding of response to treatment, including emerging evolution-based therapy strategies.
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24
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Winans JB, Wucher BR, Nadell CD. Multispecies biofilm architecture determines bacterial exposure to phages. PLoS Biol 2022; 20:e3001913. [PMID: 36548227 PMCID: PMC9778933 DOI: 10.1371/journal.pbio.3001913] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 11/14/2022] [Indexed: 12/24/2022] Open
Abstract
Numerous ecological interactions among microbes-for example, competition for space and resources, or interaction among phages and their bacterial hosts-are likely to occur simultaneously in multispecies biofilm communities. While biofilms formed by just a single species occur, multispecies biofilms are thought to be more typical of microbial communities in the natural environment. Previous work has shown that multispecies biofilms can increase, decrease, or have no measurable impact on phage exposure of a host bacterium living alongside another species that the phages cannot target. The reasons underlying this variability are not well understood, and how phage-host encounters change within multispecies biofilms remains mostly unexplored at the cellular spatial scale. Here, we study how the cellular scale architecture of model 2-species biofilms impacts cell-cell and cell-phage interactions controlling larger scale population and community dynamics. Our system consists of dual culture biofilms of Escherichia coli and Vibrio cholerae under exposure to T7 phages, which we study using microfluidic culture, high-resolution confocal microscopy imaging, and detailed image analysis. As shown previously, sufficiently mature biofilms of E. coli can protect themselves from phage exposure via their curli matrix. Before this stage of biofilm structural maturity, E. coli is highly susceptible to phages; however, we show that these bacteria can gain lasting protection against phage exposure if they have become embedded in the bottom layers of highly packed groups of V. cholerae in co-culture. This protection, in turn, is dependent on the cell packing architecture controlled by V. cholerae biofilm matrix secretion. In this manner, E. coli cells that are otherwise susceptible to phage-mediated killing can survive phage exposure in the absence of de novo resistance evolution. While co-culture biofilm formation with V. cholerae can confer phage protection to E. coli, it comes at the cost of competing with V. cholerae and a disruption of normal curli-mediated protection for E. coli even in dual species biofilms grown over long time scales. This work highlights the critical importance of studying multispecies biofilm architecture and its influence on the community dynamics of bacteria and phages.
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Affiliation(s)
- James B. Winans
- Department of Biological Sciences, Dartmouth, Hanover, New Hampshire, United States of America
| | - Benjamin R. Wucher
- Department of Biological Sciences, Dartmouth, Hanover, New Hampshire, United States of America
| | - Carey D. Nadell
- Department of Biological Sciences, Dartmouth, Hanover, New Hampshire, United States of America
- * E-mail:
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25
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Extracellular Vesicles Contribute to Mixed-Fungal Species Competition during Biofilm Initiation. mBio 2022; 13:e0298822. [PMID: 36377868 PMCID: PMC9765065 DOI: 10.1128/mbio.02988-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Extracellular vesicles commonly modulate interactions among cellular communities. Recent studies demonstrate that biofilm maturation features, including matrix production, drug resistance, and dispersion, require the delivery of a core protein and carbohydrate vesicle cargo in Candida species. The function of the vesicle cargo for these advanced-phase biofilm characteristics appears to be conserved across Candida species. Mixed-species interactions in mature biofilms indicate that vesicle cargo serves a cooperative role in preserving the community. Here, we define the function of biofilm-associated vesicles for biofilm initiation both within and among five species across the Candida genus. We found similar vesicle cargo functions for several conserved proteins across species, based on the behavior of mutants. Repletion of the adhesion environment with wild-type vesicles returned the community phenotype toward reference levels in intraspecies experiments. However, cross-species vesicle complementation did not restore the wild-type biology and in fact drove the phenotype in the opposite direction for most cross-species interactions. Further study of mixed-species biofilm adhesion and exogenous wild-type vesicle administration similarly demonstrated competitive interactions. Our studies indicate that similar vesicle cargoes contribute to biofilm initiation. However, vesicles from disparate species serve an interference competitive role in mixed-Candida species scenarios. IMPORTANCE Candida species commonly form mixed-species biofilms with other Candida species and bacteria. In the established biofilm state, vesicle cargo delivers public goods to support the mature community. At biofilm initiation, however, vesicles play a negative role in cross-species interactions, presumably to allow species to gain a survival advantage. These observations and recent reports reveal that vesicle cargo has both cooperative and competitive roles among Candida species, depending on the needs of the community biofilm formation.
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26
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Morris RJ, Stevenson D, Sukhodub T, Stanley-Wall NR, MacPhee CE. Density and temperature controlled fluid extraction in a bacterial biofilm is determined by poly-γ-glutamic acid production. NPJ Biofilms Microbiomes 2022; 8:98. [PMID: 36528619 PMCID: PMC9759580 DOI: 10.1038/s41522-022-00361-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 11/29/2022] [Indexed: 12/23/2022] Open
Abstract
A hallmark of microbial biofilms is the self-production of an extracellular molecular matrix that encases the resident cells. The matrix provides protection from the environment, while spatial heterogeneity of gene expression influences the structural morphology and colony spreading dynamics. Bacillus subtilis is a model bacterial system used to uncover the regulatory pathways and key building blocks required for biofilm growth and development. In this work, we report on the emergence of a highly active population of bacteria during the early stages of biofilm formation, facilitated by the extraction of fluid from the underlying agar substrate. We trace the origin of this fluid extraction to the production of poly-γ-glutamic acid (PGA). The flagella-dependent activity develops behind a moving front of fluid that propagates from the boundary of the biofilm towards the interior. The extent of fluid proliferation is controlled by the presence of extracellular polysaccharides (EPS). We also find that PGA production is positively correlated with higher temperatures, resulting in high-temperature mature biofilm morphologies that are distinct from the rugose colony biofilm architecture typically associated with B. subtilis. Although previous reports have suggested that PGA production does not play a major role in biofilm morphology in the undomesticated isolate NCIB 3610, our results suggest that this strain produces distinct biofilm matrices in response to environmental conditions.
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Affiliation(s)
- Ryan J. Morris
- grid.4305.20000 0004 1936 7988National Biofilms Innovation Centre, School of Physics and Astronomy, The University of Edinburgh, Edinburgh, EH9 3FD UK
| | - David Stevenson
- grid.8241.f0000 0004 0397 2876Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, DD1 5EH UK
| | - Tetyana Sukhodub
- grid.8241.f0000 0004 0397 2876Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, DD1 5EH UK
| | - Nicola R. Stanley-Wall
- grid.8241.f0000 0004 0397 2876Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, DD1 5EH UK
| | - Cait E. MacPhee
- grid.4305.20000 0004 1936 7988National Biofilms Innovation Centre, School of Physics and Astronomy, The University of Edinburgh, Edinburgh, EH9 3FD UK
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27
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Vibrio parahaemolyticus Isolates from Asian Green Mussel: Molecular Characteristics, Virulence and Their Inhibition by Chitooligosaccharide-Tea Polyphenol Conjugates. Foods 2022; 11:foods11244048. [PMID: 36553790 PMCID: PMC9778124 DOI: 10.3390/foods11244048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/06/2022] [Accepted: 12/12/2022] [Indexed: 12/16/2022] Open
Abstract
Fifty isolates of Vibrio parahaemolyticus were tested for pathogenicity, biofilm formation, motility, and antibiotic resistance. Antimicrobial activity of chitooligosaccharide (COS)-tea polyphenol conjugates against all isolates was also studied. Forty-three isolates were randomly selected from 520 isolates from Asian green mussel (Perna viridis) grown on CHROMagarTM Vibrio agar plate. Six isolates were acquired from stool specimens of diarrhea patients. One laboratory strain was V. parahaemolyticus PSU.SCB.16S.14. Among all isolates tested, 12% of V. parahaemolyticus carried the tdh+trh- gene and were positive toward Kanagawa phenomenon test. All of V. parahaemolyticus isolates could produce biofilm and showed relatively strong motile ability. When COS-catechin conjugate (COS-CAT) and COS-epigallocatechin-3-gallate conjugate (COS-EGCG) were examined for their inhibitory effect against V. parahaemolyticus, the former showed the higher bactericidal activity with the MBC value of 1.024 mg/mL against both pathogenic and non-pathogenic strains. Most of the representative Asian green mussel V. parahaemolyticus isolates exhibited high sensitivity to all antibiotics, whereas one isolate showed the intermediate resistance to cefuroxime. However, the representative clinical isolates were highly resistant to nine types of antibiotics and had multiple antibiotic resistance (MAR) index of 0.64. Thus, COS-CAT could be used as potential antimicrobial agent for controlling V. parahaemolyticus-causing disease in Asian green mussel.
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28
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Charlton SGV, Kurz DL, Geisel S, Jimenez-Martinez J, Secchi E. The role of biofilm matrix composition in controlling colony expansion and morphology. Interface Focus 2022; 12:20220035. [PMID: 36330326 PMCID: PMC9560791 DOI: 10.1098/rsfs.2022.0035] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 09/09/2022] [Indexed: 08/01/2023] Open
Abstract
Biofilms are biological viscoelastic gels composed of bacterial cells embedded in a self-secreted polymeric extracellular matrix (ECM). In environmental settings, such as in the rhizosphere and phyllosphere, biofilm colonization occurs at the solid-air interface. The biofilms' ability to colonize and expand over these surfaces depends on the formation of osmotic gradients and ECM viscoelastic properties. In this work, we study the influence of biofilm ECM components on its viscoelasticity and expansion, using the model organism Bacillus subtilis and deletion mutants of its three major ECM components, TasA, EPS and BslA. Using a multi-scale approach, we quantified macro-scale viscoelasticity and expansion dynamics. Furthermore, we used a microsphere assay to visualize the micro-scale expansion patterns. We find that the viscoelastic phase angle Φ is likely the best viscoelastic parameter correlating to biofilm expansion dynamics. Moreover, we quantify the sensitivity of the biofilm to changes in substrate water potential as a function of ECM composition. Finally, we find that the deletion of ECM components significantly increases the coherence of micro-scale colony expansion patterns. These results demonstrate the influence of ECM viscoelasticity and substrate water potential on the expansion of biofilm colonies on wet surfaces at the air-solid interface, commonly found in natural environments.
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Affiliation(s)
- Samuel G. V. Charlton
- Department of Civil, Environmental and Geomatic Engineering, Institute of Environmental Engineering, ETH Zürich, Zürich, Switzerland
| | - Dorothee L. Kurz
- Department of Civil, Environmental and Geomatic Engineering, Institute of Environmental Engineering, ETH Zürich, Zürich, Switzerland
- Department Water Resources and Drinking Water, Swiss Federal Institute of Aquatic Science and Technology, Eawag, Dübendorf, Switzerland
| | - Steffen Geisel
- Department of Materials, Soft Materials, ETH Zürich, Zürich, Switzerland
| | - Joaquin Jimenez-Martinez
- Department of Civil, Environmental and Geomatic Engineering, Institute of Environmental Engineering, ETH Zürich, Zürich, Switzerland
- Department Water Resources and Drinking Water, Swiss Federal Institute of Aquatic Science and Technology, Eawag, Dübendorf, Switzerland
| | - Eleonora Secchi
- Department of Civil, Environmental and Geomatic Engineering, Institute of Environmental Engineering, ETH Zürich, Zürich, Switzerland
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29
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Eigentler L, Davidson FA, Stanley-Wall NR. Mechanisms driving spatial distribution of residents in colony biofilms: an interdisciplinary perspective. Open Biol 2022; 12:220194. [PMID: 36514980 PMCID: PMC9748781 DOI: 10.1098/rsob.220194] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Biofilms are consortia of microorganisms that form collectives through the excretion of extracellular matrix compounds. The importance of biofilms in biological, industrial and medical settings has long been recognized due to their emergent properties and impact on surrounding environments. In laboratory situations, one commonly used approach to study biofilm formation mechanisms is the colony biofilm assay, in which cell communities grow on solid-gas interfaces on agar plates after the deposition of a population of founder cells. The residents of a colony biofilm can self-organize to form intricate spatial distributions. The assay is ideally suited to coupling with mathematical modelling due to the ability to extract a wide range of metrics. In this review, we highlight how interdisciplinary approaches have provided deep insights into mechanisms causing the emergence of these spatial distributions from well-mixed inocula.
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Affiliation(s)
- Lukas Eigentler
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK,Mathematics, School of Science and Engineering, University of Dundee, Dundee DD1 4HN, UK
| | - Fordyce A. Davidson
- Mathematics, School of Science and Engineering, University of Dundee, Dundee DD1 4HN, UK
| | - Nicola R. Stanley-Wall
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
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30
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Asp M, Jutzeler E, Kochanowski J, Kerr K, Song D, Gupta S, Carroll B, Patteson A. A Torsion-Based Rheometer for Measuring Viscoelastic Material Properties. BIOPHYSICIST (ROCKVILLE, MD.) 2022; 3:94-105. [PMID: 38098945 PMCID: PMC10720878 DOI: 10.35459/tbp.2020.000172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
Rheology and the study of viscoelastic materials are an integral part of engineering and the study of biophysical systems. Tissue rheology is even used in the study of cancer and other diseases. However, the cost of a rheometer is feasible only for colleges, universities, and research laboratories. Even if a rheometer can be purchased, it is bulky and delicately calibrated, limiting its usefulness to the laboratory itself. The design presented here is less than a tenth of the cost of a professional rheometer. The design is also portable, making it the ideal solution to introduce viscoelasticity to high school students as well as for use in the field for obtaining rheological data.
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Affiliation(s)
- Merrill Asp
- Physics Department and BioInspired Institute, Syracuse University, Syracuse, NY, USA
| | - Elise Jutzeler
- Physics Department and BioInspired Institute, Syracuse University, Syracuse, NY, USA
- Jamesville-Dewitt High School, Syracuse, NY, USA
| | - Jakub Kochanowski
- Physics Department and BioInspired Institute, Syracuse University, Syracuse, NY, USA
| | - Katherine Kerr
- Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA, USA
- Department of Bioengineering, Purdue University, West Lafayette, IN, USA
| | - Dawei Song
- Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Sarthak Gupta
- Physics Department and BioInspired Institute, Syracuse University, Syracuse, NY, USA
| | - Bobby Carroll
- Physics Department and BioInspired Institute, Syracuse University, Syracuse, NY, USA
| | - Alison Patteson
- Physics Department and BioInspired Institute, Syracuse University, Syracuse, NY, USA
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31
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Czech L, Gertzen C, Smits SHJ, Bremer E. Guilty by association: importers, exporters and
MscS
‐type mechanosensitive channels encoded in biosynthetic gene clusters for the stress‐protectant ectoine. Environ Microbiol 2022; 24:5306-5331. [DOI: 10.1111/1462-2920.16203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 09/07/2022] [Indexed: 11/28/2022]
Affiliation(s)
- Laura Czech
- Department of Biology, Laboratory for Microbiology and Center for Synthetic Microbiology (SYNMIKRO) Philipps‐University Marburg Marburg Germany
- Department of Chemistry and Center for Synthetic Microbiology (SYNMIKRO) Philipps‐University Marburg Marburg Germany
| | - Christoph Gertzen
- Center for Structural Studies (CSS) Heinrich‐Heine‐University Düsseldorf Düsseldorf Germany
- Institute of Pharmaceutical and Medicinal Chemistry Heinrich‐Heine‐University Düsseldorf Düsseldorf Germany
| | - Sander H. J. Smits
- Center for Structural Studies (CSS) Heinrich‐Heine‐University Düsseldorf Düsseldorf Germany
- Institute of Biochemistry Heinrich Heine University Düsseldorf Düsseldorf Germany
| | - Erhard Bremer
- Department of Biology, Laboratory for Microbiology and Center for Synthetic Microbiology (SYNMIKRO) Philipps‐University Marburg Marburg Germany
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32
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Sequence Polymorphisms in Vibrio cholerae HapR Affect Biofilm Formation under Aerobic and Anaerobic Conditions. Appl Environ Microbiol 2022; 88:e0104422. [PMID: 35969071 PMCID: PMC9469714 DOI: 10.1128/aem.01044-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We investigated the influence of hapR sequence mutations on the biofilm formation of Vibrio cholerae. In this study, hapR sequences from 85 V. cholerae strains belonging to both pandemic and nonpandemic serogroup were investigated through phylogenetic and sequence analyses. Biofilm formation assays under aerobic and anaerobic conditions were also performed. Sequence variations include single point mutations and insertions/deletions (indels) leading to either truncated or frameshifted HapR. Population structure analysis revealed two major hapR haplogroups, hapR1 and hapR2. Phylogenetic reconstruction displayed a hypothetical ancestral hapR sequence located within the hapR1 haplogroup. Higher numbers of single nucleotide polymorphisms and genetic diversity indices were observed in hapR1, while indels occurred dominantly in hapR2. Aerobic conditions supported more robust biofilms compared to anaerobic conditions. Strains with frameshifted HapR produced the largest amount of biofilm under both oxygen conditions. Quantitative real-time PCR assay confirmed that strains with truncated and frameshifted HapR resulted in a nonfunctional regulator as exhibited by the significantly low hapA gene expression. The present study shows that HapR mutations had a strong influence on biofilm formation and that sequence polymorphisms leading to the disruption of DNA-binding sites or dimerization of the HapR will result in more-robust V. cholerae biofilms. IMPORTANCE Our study revealed an ancestral hapR sequence from a phylogenetic reconstruction that displayed the evolutionary lineage of the nonpandemic to the pandemic strains. Here, we established hapR1 and hapR2 as major hapR haplogroups. The association of the O1 and O139 serogroups with the hapR2 haplogroup demonstrated the distinction of hapR2 in causing cholera infection. Moreover, mutations in this regulator that could lead to the disruption of transcription factor-binding sites or dimerization of the HapR can significantly affect the biofilm formation of V. cholerae. These observations on the relationship of the hapR polymorphism and V. cholerae biofilm formation will provide additional considerations for future biofilm studies and insights into the epidemiology of the pathogen that could ultimately help in the surveillance and mitigation of future cholera disease outbreaks.
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33
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Teschler JK, Nadell CD, Drescher K, Yildiz FH. Mechanisms Underlying Vibrio cholerae Biofilm Formation and Dispersion. Annu Rev Microbiol 2022; 76:503-532. [PMID: 35671532 DOI: 10.1146/annurev-micro-111021-053553] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Biofilms are a widely observed growth mode in which microbial communities are spatially structured and embedded in a polymeric extracellular matrix. Here, we focus on the model bacterium Vibrio cholerae and summarize the current understanding of biofilm formation, including initial attachment, matrix components, community dynamics, social interactions, molecular regulation, and dispersal. The regulatory network that orchestrates the decision to form and disperse from biofilms coordinates various environmental inputs. These cues are integrated by several transcription factors, regulatory RNAs, and second-messenger molecules, including bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP). Through complex mechanisms, V. cholerae weighs the energetic cost of forming biofilms against the benefits of protection and social interaction that biofilms provide. Expected final online publication date for the Annual Review of Microbiology, Volume 76 is September 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Jennifer K Teschler
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, California, USA;
| | - Carey D Nadell
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire, USA
| | | | - Fitnat H Yildiz
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, California, USA;
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34
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Li K, Liao J, Wei M, Qiu S, Wu W, Zhao Y, Wang H, Liu Q, Liu F, Chang C. The Xanthomonas citri Reverse Fitness Deficiency by Activating a Novel β-Glucosidase Under Low Osmostress. Front Microbiol 2022; 13:887967. [PMID: 35586864 PMCID: PMC9108719 DOI: 10.3389/fmicb.2022.887967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 03/17/2022] [Indexed: 11/13/2022] Open
Abstract
Bacteria can withstand various types of environmental osmostress. A sudden rise in osmostress affects bacterial cell growth that is countered by activating special genes. The change of osmostress is generally a slow process under the natural environment. However, the collective response of bacteria to low osmostress remains unknown. This study revealed that the deletion of phoP (ΔphoP) from X. citri significantly compromised the growth and virulence as compared to the wild-type strain. Interestingly, low osmostress reversed physiological deficiencies of X. citri phoP mutant related to bacterial growth and virulence. The results also provided biochemical and genetic evidence that the physiological deficiency of phoP mutant can be reversed by low osmostress induced β-glucosidase (BglS) expression. Based on the data, this study proposes a novel regulatory mechanism of a novel β-glucosidase activation in X. citri through low osmostress to reverse the fitness deficiency.
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Affiliation(s)
- Kaihuai Li
- College of Plant Protection, Integrate Microbiology Research Center, South China Agricultural University, Guangzhou, China
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Jinxing Liao
- College of Plant Protection, Integrate Microbiology Research Center, South China Agricultural University, Guangzhou, China
| | - Ming Wei
- College of Plant Protection, Integrate Microbiology Research Center, South China Agricultural University, Guangzhou, China
| | - Shanxu Qiu
- College of Plant Protection, Integrate Microbiology Research Center, South China Agricultural University, Guangzhou, China
| | - Weiyin Wu
- College of Plant Protection, Integrate Microbiology Research Center, South China Agricultural University, Guangzhou, China
| | - Yancun Zhao
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Haihong Wang
- College of Life Sciences, South China Agricultural University, Guangzhou, China
| | - Qiongguang Liu
- College of Plant Protection, Integrate Microbiology Research Center, South China Agricultural University, Guangzhou, China
| | - Fengquan Liu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China
- *Correspondence: Fengquan Liu,
| | - Changqing Chang
- College of Plant Protection, Integrate Microbiology Research Center, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
- Changqing Chang,
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35
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Katharios-Lanwermeyer S, O’Toole GA. Biofilm Maintenance as an Active Process: Evidence that Biofilms Work Hard to Stay Put. J Bacteriol 2022; 204:e0058721. [PMID: 35311557 PMCID: PMC9017327 DOI: 10.1128/jb.00587-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Biofilm formation represents a critical strategy whereby bacteria can tolerate otherwise damaging environmental stressors and antimicrobial insults. While the mechanisms bacteria use to establish a biofilm and disperse from these communities have been well-studied, we have only a limited understanding of the mechanisms required to maintain these multicellular communities. Indeed, until relatively recently, it was not clear that maintaining a mature biofilm could be considered an active, regulated process with dedicated machinery. Using Pseudomonas aeruginosa as a model system, we review evidence from recent studies that support the model that maintenance of these persistent, surface-attached communities is indeed an active process. Biofilm maintenance mechanisms include transcriptional regulation and second messenger signaling (including the production of extracellular polymeric substances). We also discuss energy-conserving pathways that play a key role in the maintenance of these communities. We hope to highlight the need for further investigation to uncover novel biofilm maintenance pathways and suggest the possibility that such pathways can serve as novel antibiofilm targets.
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Affiliation(s)
| | - G. A. O’Toole
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
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36
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Asp ME, Ho Thanh MT, Germann DA, Carroll RJ, Franceski A, Welch RD, Gopinath A, Patteson AE. Spreading rates of bacterial colonies depend on substrate stiffness and permeability. PNAS NEXUS 2022; 1:pgac025. [PMID: 36712798 PMCID: PMC9802340 DOI: 10.1093/pnasnexus/pgac025] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/25/2022] [Accepted: 03/09/2022] [Indexed: 02/01/2023]
Abstract
The ability of bacteria to colonize and grow on different surfaces is an essential process for biofilm development. Here, we report the use of synthetic hydrogels with tunable stiffness and porosity to assess physical effects of the substrate on biofilm development. Using time-lapse microscopy to track the growth of expanding Serratia marcescens colonies, we find that biofilm colony growth can increase with increasing substrate stiffness, unlike what is found on traditional agar substrates. Using traction force microscopy-based techniques, we find that biofilms exert transient stresses correlated over length scales much larger than a single bacterium, and that the magnitude of these forces also increases with increasing substrate stiffness. Our results are consistent with a model of biofilm development in which the interplay between osmotic pressure arising from the biofilm and the poroelastic response of the underlying substrate controls biofilm growth and morphology.
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Affiliation(s)
- Merrill E Asp
- Physics Department, Syracuse University, Syracuse, NY 13244, USA,BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Minh-Tri Ho Thanh
- Physics Department, Syracuse University, Syracuse, NY 13244, USA,BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Danielle A Germann
- Physics Department, Syracuse University, Syracuse, NY 13244, USA,BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Robert J Carroll
- Physics Department, Syracuse University, Syracuse, NY 13244, USA,BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Alana Franceski
- BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA,Biology Department, Syracuse University, Syracuse, NY 13244, USA
| | - Roy D Welch
- BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA,Biology Department, Syracuse University, Syracuse, NY 13244, USA
| | - Arvind Gopinath
- Department of Bioengineering, University of California, Merced, Merced, CA 95343, USA,Health Sciences Research Institute, University of California, Merced, Merced, CA 95343, USA
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37
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Bremer E, Hoffmann T, Dempwolff F, Bedrunka P, Bange G. The many faces of the unusual biofilm activator RemA. Bioessays 2022; 44:e2200009. [PMID: 35289951 DOI: 10.1002/bies.202200009] [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: 01/11/2022] [Revised: 02/28/2022] [Accepted: 03/02/2022] [Indexed: 11/08/2022]
Abstract
Biofilms can be viewed as tissue-like structures in which microorganisms are organized in a spatial and functional sophisticated manner. Biofilm formation requires the orchestration of a highly integrated network of regulatory proteins to establish cell differentiation and production of a complex extracellular matrix. Here, we discuss the role of the essential Bacillus subtilis biofilm activator RemA. Despite intense research on biofilms, RemA is a largely underappreciated regulatory protein. RemA forms donut-shaped octamers with the potential to assemble into dimeric superstructures. The presumed DNA-binding mode suggests that RemA organizes its target DNA into nucleosome-like structures, which are the basis for its role as transcriptional activator. We discuss how RemA affects gene expression in the context of biofilm formation, and its regulatory interplay with established components of the biofilm regulatory network, such as SinR, SinI, SlrR, and SlrA. We emphasize the additional role of RemA played in nitrogen metabolism and osmotic-stress adjustment.
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Affiliation(s)
- Erhard Bremer
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany
| | - Tamara Hoffmann
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany
| | - Felix Dempwolff
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany
| | - Patricia Bedrunka
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany
| | - Gert Bange
- Center for Synthetic Microbiology (SYNMIKRO), Philipps-University Marburg, Marburg, Germany.,Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
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38
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Bhattacharjee T, Amchin DB, Alert R, Ott JA, Datta SS. Chemotactic smoothing of collective migration. eLife 2022; 11:e71226. [PMID: 35257660 PMCID: PMC8903832 DOI: 10.7554/elife.71226] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Accepted: 01/24/2022] [Indexed: 12/24/2022] Open
Abstract
Collective migration-the directed, coordinated motion of many self-propelled agents-is a fascinating emergent behavior exhibited by active matter with functional implications for biological systems. However, how migration can persist when a population is confronted with perturbations is poorly understood. Here, we address this gap in knowledge through studies of bacteria that migrate via directed motion, or chemotaxis, in response to a self-generated nutrient gradient. We find that bacterial populations autonomously smooth out large-scale perturbations in their overall morphology, enabling the cells to continue to migrate together. This smoothing process arises from spatial variations in the ability of cells to sense and respond to the local nutrient gradient-revealing a population-scale consequence of the manner in which individual cells transduce external signals. Altogether, our work provides insights to predict, and potentially control, the collective migration and morphology of cellular populations and diverse other forms of active matter.
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Affiliation(s)
- Tapomoy Bhattacharjee
- The Andlinger Center for Energy and the Environment, Princeton UniversityPrincetonUnited States
| | - Daniel B Amchin
- Department of Chemical and Biological Engineering, Princeton UniversityPrincetonUnited States
| | - Ricard Alert
- Lewis-Sigler Institute for Integrative Genomics, Princeton UniversityPrincetonUnited States
- Princeton Center for Theoretical Science, Princeton UniversityPrincetonUnited States
| | - Jenna Anne Ott
- Department of Chemical and Biological Engineering, Princeton UniversityPrincetonUnited States
| | - Sujit Sankar Datta
- Department of Chemical and Biological Engineering, Princeton UniversityPrincetonUnited States
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39
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Patteson AE, Asp ME, Janmey PA. Materials science and mechanosensitivity of living matter. APPLIED PHYSICS REVIEWS 2022; 9:011320. [PMID: 35392267 PMCID: PMC8969880 DOI: 10.1063/5.0071648] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 02/08/2022] [Indexed: 06/14/2023]
Abstract
Living systems are composed of molecules that are synthesized by cells that use energy sources within their surroundings to create fascinating materials that have mechanical properties optimized for their biological function. Their functionality is a ubiquitous aspect of our lives. We use wood to construct furniture, bacterial colonies to modify the texture of dairy products and other foods, intestines as violin strings, bladders in bagpipes, and so on. The mechanical properties of these biological materials differ from those of other simpler synthetic elastomers, glasses, and crystals. Reproducing their mechanical properties synthetically or from first principles is still often unattainable. The challenge is that biomaterials often exist far from equilibrium, either in a kinetically arrested state or in an energy consuming active state that is not yet possible to reproduce de novo. Also, the design principles that form biological materials often result in nonlinear responses of stress to strain, or force to displacement, and theoretical models to explain these nonlinear effects are in relatively early stages of development compared to the predictive models for rubberlike elastomers or metals. In this Review, we summarize some of the most common and striking mechanical features of biological materials and make comparisons among animal, plant, fungal, and bacterial systems. We also summarize some of the mechanisms by which living systems develop forces that shape biological matter and examine newly discovered mechanisms by which cells sense and respond to the forces they generate themselves, which are resisted by their environment, or that are exerted upon them by their environment. Within this framework, we discuss examples of how physical methods are being applied to cell biology and bioengineering.
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Affiliation(s)
- Alison E. Patteson
- Physics Department and BioInspired Institute, Syracuse University, Syracuse NY, 13244, USA
| | - Merrill E. Asp
- Physics Department and BioInspired Institute, Syracuse University, Syracuse NY, 13244, USA
| | - Paul A. Janmey
- Institute for Medicine and Engineering and Departments of Physiology and Physics & Astronomy, University of Pennsylvania, Philadelphia PA, 19104, USA
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40
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Hu H, Kang X, Shan Z, Yang X, Bing W, Wu L, Ge H, Ji H. A DNase-mimetic artificial enzyme for the eradication of drug-resistant bacterial biofilm infections. NANOSCALE 2022; 14:2676-2685. [PMID: 35107481 DOI: 10.1039/d1nr07629a] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The construction of multifunctional nano-enzymes is a feasible strategy for fighting multi-drug resistant (MDR) bacterial biofilm-associated infections. Extracellular DNA (eDNA) is an important functional part of biofilm formation, including the initial adherence of bacteria to subsequent development and eventual maturation. A nano-enzyme platform of graphene oxide-based nitrilotriacetic acid-cerium(IV) composite (GO-NTA-Ce) against bacterial biofilm infection has been developed. When located at the site of bacteria-associated infection, GO-NTA-Ce could inhibit the biofilm formation and effectively disperse the formed biofilm by degrading the eDNA. In addition to Ce-mediated deoxyribonuclease (DNase)-like activity, near-infrared laser irradiation of GO-NTA-Ce could produce local hyperthermia to kill the bacteria that lost the protection by the biofilm matrix. In addition, graphene is also a new green broad-spectrum antimicrobial material that can exert its antimicrobial effects through physical damage and chemical damage. In short, our GO-NTA-Ce nano-enzyme platform is capable of effectively eradicating drug-resistant bacterial biofilm infections through the triple action of DNase-like enzyme properties, photothermal therapy, and graphene-based antimicrobial activity, and the nano-composite has excellent potential for the treatment of MDR bacterial biofilm infections.
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Affiliation(s)
- Haolu Hu
- School of Chemistry and Life Science, Advanced Institute of Materials Science, Changchun University of Technology, 2055 Yanan Street, Changchun 130012, People's Republic of China.
- School of Public Health, Nantong University, No. 9, Seyuan Road, Nantong 226019, People's Republic of China.
| | - Xiaoxia Kang
- School of Public Health, Nantong University, No. 9, Seyuan Road, Nantong 226019, People's Republic of China.
| | - Zhenhua Shan
- School of Chemistry and Life Science, Advanced Institute of Materials Science, Changchun University of Technology, 2055 Yanan Street, Changchun 130012, People's Republic of China.
| | - Xiaoxiao Yang
- School of Public Health, Nantong University, No. 9, Seyuan Road, Nantong 226019, People's Republic of China.
| | - Wei Bing
- School of Chemistry and Life Science, Advanced Institute of Materials Science, Changchun University of Technology, 2055 Yanan Street, Changchun 130012, People's Republic of China.
| | - Li Wu
- School of Public Health, Nantong University, No. 9, Seyuan Road, Nantong 226019, People's Republic of China.
| | - Haiyan Ge
- School of Chemistry and Pharmaceutical Engineering, Shandong First Medical University & Shandong Academy of Medical Science, Taian, Shandong, 271016, People's Republic of China.
| | - Haiwei Ji
- School of Public Health, Nantong University, No. 9, Seyuan Road, Nantong 226019, People's Republic of China.
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41
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Padgett-Pagliai KA, Pagliai FA, da Silva DR, Gardner CL, Lorca GL, Gonzalez CF. Osmotic stress induces long-term biofilm survival in Liberibacter crescens. BMC Microbiol 2022; 22:52. [PMID: 35148684 PMCID: PMC8832773 DOI: 10.1186/s12866-022-02453-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 01/21/2022] [Indexed: 11/24/2022] Open
Abstract
Citrus greening, also known as Huanglongbing (HLB), is a devastating citrus plant disease caused predominantly by Liberibacter asiaticus. While nearly all Liberibacter species remain uncultured, here we used the culturable L. crescens BT-1 as a model to examine physiological changes in response to the variable osmotic conditions and nutrient availability encountered within the citrus host. Similarly, physiological responses to changes in growth temperature and dimethyl sulfoxide concentrations were also examined, due to their use in many of the currently employed therapies to control the spread of HLB. Sublethal heat stress was found to induce the expression of genes related to tryptophan biosynthesis, while repressing the expression of ribosomal proteins. Osmotic stress induces expression of transcriptional regulators involved in expression of extracellular structures, while repressing the biosynthesis of fatty acids and aromatic amino acids. The effects of osmotic stress were further evaluated by quantifying biofilm formation of L. crescens in presence of increasing sucrose concentrations at different stages of biofilm formation, where sucrose-induced osmotic stress delayed initial cell attachment while enhancing long-term biofilm viability. Our findings revealed that exposure to osmotic stress is a significant contributing factor to the long term survival of L. crescens and, possibly, to the pathogenicity of other Liberibacter species.
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Affiliation(s)
- Kaylie A Padgett-Pagliai
- Department of Microbiology and Cell Science, Genetics Institute, Institute of Food and Agricultural Sciences, University of Florida, 2033 Mowry Road, PO Box 103610, Gainesville, FL, 32610-3610, USA
| | - Fernando A Pagliai
- Department of Microbiology and Cell Science, Genetics Institute, Institute of Food and Agricultural Sciences, University of Florida, 2033 Mowry Road, PO Box 103610, Gainesville, FL, 32610-3610, USA
| | - Danilo R da Silva
- Department of Microbiology and Cell Science, Genetics Institute, Institute of Food and Agricultural Sciences, University of Florida, 2033 Mowry Road, PO Box 103610, Gainesville, FL, 32610-3610, USA
| | - Christopher L Gardner
- Department of Microbiology and Cell Science, Genetics Institute, Institute of Food and Agricultural Sciences, University of Florida, 2033 Mowry Road, PO Box 103610, Gainesville, FL, 32610-3610, USA
| | - Graciela L Lorca
- Department of Microbiology and Cell Science, Genetics Institute, Institute of Food and Agricultural Sciences, University of Florida, 2033 Mowry Road, PO Box 103610, Gainesville, FL, 32610-3610, USA
| | - Claudio F Gonzalez
- Department of Microbiology and Cell Science, Genetics Institute, Institute of Food and Agricultural Sciences, University of Florida, 2033 Mowry Road, PO Box 103610, Gainesville, FL, 32610-3610, USA.
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42
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Slow expanders invade by forming dented fronts in microbial colonies. Proc Natl Acad Sci U S A 2022; 119:2108653119. [PMID: 34983839 PMCID: PMC8740590 DOI: 10.1073/pnas.2108653119] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/08/2021] [Indexed: 12/19/2022] Open
Abstract
Living organisms never cease to evolve, so there is a significant interest in predicting and controlling evolution in all branches of life sciences. The most basic question is whether a trait should increase or decrease in a given environment. The answer seems to be trivial for traits such as the growth rate in a bioreactor or the expansion rate of a tumor. Yet, it has been suggested that such traits can decrease, rather than increase, during evolution. Here, we report a mutant that outcompeted the ancestor despite having a slower expansion velocity when in isolation. To explain this observation, we developed and validated a theory that describes spatial competition between organisms with different expansion rates and arbitrary competitive interactions. Most organisms grow in space, whether they are viruses spreading within a host tissue or invasive species colonizing a new continent. Evolution typically selects for higher expansion rates during spatial growth, but it has been suggested that slower expanders can take over under certain conditions. Here, we report an experimental observation of such population dynamics. We demonstrate that mutants that grow slower in isolation nevertheless win in competition, not only when the two types are intermixed, but also when they are spatially segregated into sectors. The latter was thought to be impossible because previous studies focused exclusively on the global competitions mediated by expansion velocities, but overlooked the local competitions at sector boundaries. Local competition, however, can enhance the velocity of either type at the sector boundary and thus alter expansion dynamics. We developed a theory that accounts for both local and global competitions and describes all possible sector shapes. In particular, the theory predicted that a slower on its own, but more competitive, mutant forms a dented V-shaped sector as it takes over the expansion front. Such sectors were indeed observed experimentally, and their shapes matched quantitatively with the theory. In simulations, we further explored several mechanisms that could provide slow expanders with a local competitive advantage and showed that they are all well-described by our theory. Taken together, our results shed light on previously unexplored outcomes of spatial competition and establish a universal framework to understand evolutionary and ecological dynamics in expanding populations.
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43
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Tam AKY, Harding B, Green JEF, Balasuriya S, Binder BJ. Thin-film lubrication model for biofilm expansion under strong adhesion. Phys Rev E 2022; 105:014408. [PMID: 35193209 DOI: 10.1103/physreve.105.014408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 11/26/2021] [Indexed: 06/14/2023]
Abstract
Understanding microbial biofilm growth is important to public health because biofilms are a leading cause of persistent clinical infections. In this paper, we develop a thin-film model for microbial biofilm growth on a solid substratum to which it adheres strongly. We model biofilms as two-phase viscous fluid mixtures of living cells and extracellular fluid. The model explicitly tracks the movement, depletion, and uptake of nutrients and incorporates cell proliferation via a nutrient-dependent source term. Notably, our thin-film reduction is two dimensional and includes the vertical dependence of cell volume fraction. Numerical solutions show that this vertical dependence is weak for biologically feasible parameters, reinforcing results from previous models in which this dependence was neglected. We exploit this weak dependence by writing and solving a simplified one-dimensional model that is computationally more efficient than the full model. We use both the one- and two-dimensional models to predict how model parameters affect expansion speed and biofilm thickness. This analysis reveals that expansion speed depends on cell proliferation, nutrient availability, cell-cell adhesion on the upper surface, and slip on the biofilm-substratum interface. Our numerical solutions provide a means to qualitatively distinguish between the extensional flow and lubrication regimes, and quantitative predictions that can be tested in future experiments.
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Affiliation(s)
- Alexander K Y Tam
- School of Mathematical Sciences, Queensland University of Technology, Brisbane Queensland 4000, Australia
- School of Mathematics and Physics, The University of Queensland, St. Lucia Queensland 4072, Australia
- School of Mathematical Sciences, The University of Adelaide, Adelaide SA 5005, Australia
| | - Brendan Harding
- School of Mathematical Sciences, The University of Adelaide, Adelaide SA 5005, Australia
- School of Mathematics and Statistics, Victoria University of Wellington, Wellington 6140, New Zealand
| | - J Edward F Green
- School of Mathematical Sciences, The University of Adelaide, Adelaide SA 5005, Australia
| | - Sanjeeva Balasuriya
- School of Mathematical Sciences, The University of Adelaide, Adelaide SA 5005, Australia
| | - Benjamin J Binder
- School of Mathematical Sciences, The University of Adelaide, Adelaide SA 5005, Australia
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Dong F, Liu S, Zhang D, Zhang J, Wang X, Zhao H. Osmotic Pressure Induced by Extracellular Matrix Drives Bacillus Subtilis Biofilms’ Self-healing. Comput Biol Chem 2022; 97:107632. [DOI: 10.1016/j.compbiolchem.2022.107632] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 01/08/2022] [Accepted: 01/13/2022] [Indexed: 01/01/2023]
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Ziege R, Tsirigoni AM, Large B, Serra DO, Blank KG, Hengge R, Fratzl P, Bidan CM. Adaptation of Escherichia coli Biofilm Growth, Morphology, and Mechanical Properties to Substrate Water Content. ACS Biomater Sci Eng 2021; 7:5315-5325. [PMID: 34672512 PMCID: PMC8579398 DOI: 10.1021/acsbiomaterials.1c00927] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
![]()
Biofilms are complex
living materials that form as bacteria become
embedded in a matrix of self-produced protein and polysaccharide fibers.
In addition to their traditional association with chronic infections
or clogging of pipelines, biofilms currently gain interest as a potential
source of functional material. On nutritive hydrogels, micron-sized Escherichia coli cells can build centimeter-large biofilms.
During this process, bacterial proliferation, matrix production, and
water uptake introduce mechanical stresses in the biofilm that are
released through the formation of macroscopic delaminated buckles
in the third dimension. To clarify how substrate water content could
be used to tune biofilm material properties, we quantified E. coli biofilm growth, delamination dynamics, and rigidity
as a function of water content of the nutritive substrates. Time-lapse
microscopy and computational image analysis revealed that softer substrates
with high water content promote biofilm spreading kinetics, while
stiffer substrates with low water content promote biofilm delamination.
The delaminated buckles observed on biofilm cross sections appeared
more bent on substrates with high water content, while they tended
to be more vertical on substrates with low water content. Both wet
and dry biomass, accumulated over 4 days of culture, were larger in
biofilms cultured on substrates with high water content, despite extra
porosity within the matrix layer. Finally, microindentation analysis
revealed that substrates with low water content supported the formation
of stiffer biofilms. This study shows that E. coli biofilms respond to substrate water content, which might be used
for tuning their material properties in view of further applications.
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Affiliation(s)
- Ricardo Ziege
- Max Planck Institute of Colloids and Interfaces, 14476 Potsdam, Germany
| | | | - Bastien Large
- Max Planck Institute of Colloids and Interfaces, 14476 Potsdam, Germany
| | - Diego O Serra
- Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany.,Institute of Molecular and Cell Biology, 2000 Rosario, Argentina
| | - Kerstin G Blank
- Max Planck Institute of Colloids and Interfaces, 14476 Potsdam, Germany
| | - Regine Hengge
- Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany
| | - Peter Fratzl
- Max Planck Institute of Colloids and Interfaces, 14476 Potsdam, Germany
| | - Cécile M Bidan
- Max Planck Institute of Colloids and Interfaces, 14476 Potsdam, Germany
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Sun Y, Liu M, Niu M, Zhao X. Phenotypic Switching of Staphylococcus aureus Mu50 Into a Large Colony Variant Enhances Heritable Resistance Against β-Lactam Antibiotics. Front Microbiol 2021; 12:709841. [PMID: 34690952 PMCID: PMC8530407 DOI: 10.3389/fmicb.2021.709841] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 09/13/2021] [Indexed: 11/24/2022] Open
Abstract
Phenotypic heterogeneity within a bacterial population may confer new functionality and allow microorganisms to adapt to fluctuating environments. Previous work has suggested that Staphylococcus aureus could form small colony variants to avoid elimination by therapeutic antibiotics and host immunity systems. Here we show that a reversible non-pigment large colony morphology (Mu50∆lcpA-LC) was observed in S. aureus Mu50 after knocking out lcpA, coding for the LytR-CpsA-Psr family A protein. Mu50∆lcpA-LC increased resistance to β-lactam antibiotics, in addition, the enlarged cell size, enhanced spreading ability on solid medium, and reduced biofilm formation, suggesting better abilities for bacterial expansion. Moreover, the expression of spa encoding protein A was significantly increased in Mu50∆lcpA-LC. This study shows that besides the small colony variants, S. aureus could fight against antibiotics and host immunity through phenotype switching into a large colony variant.
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Affiliation(s)
- Yajun Sun
- College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - Miaomiao Liu
- College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - Mingze Niu
- College of Animal Science and Technology, Northwest A&F University, Yangling, China
| | - Xin Zhao
- College of Animal Science and Technology, Northwest A&F University, Yangling, China.,Department of Animal Science, McGill University, Montreal, QC, Canada
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The Diguanylate Cyclase YfiN of Pseudomonas aeruginosa Regulates Biofilm Maintenance in Response to Peroxide. J Bacteriol 2021; 204:e0039621. [PMID: 34694901 DOI: 10.1128/jb.00396-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas aeruginosa forms surface-attached communities that persist in the face of antimicrobial agents and environmental perturbation. Published work has found extracellular polysaccharide (EPS) production, regulation of motility and induction of stress response pathways as contributing to biofilm tolerance during such insults. However, little is known regarding the mechanism(s) whereby biofilm maintenance is regulated when exposed to such environmental challenges. Here, we provide evidence that the diguanylate cyclase YfiN is important for the regulation of biofilm maintenance when exposed to peroxide. We find that, compared to the wild type (WT), static biofilms of the ΔyfiN mutant exhibit a maintenance defect, which can be further exacerbated by exposure to peroxide (H2O2); this defect can be rescued through genetic complementation. Additionally, we found that the ΔyfiN mutant biofilms produce less c-di-GMP than WT, and that H2O2 treatment enhanced motility of surface-associated bacteria and increased cell death for the ΔyfiN mutant grown as a biofilm compared to WT biofilms. These data provide evidence that YfiN is required for biofilm maintenance by P. aeruginosa, via c-di-GMP signaling, to limit motility and protect viability in response to peroxide stress. These findings add to the growing recognition that biofilm maintenance by P. aeruginosa is an actively regulated process that is controlled, at least in part, by the wide array of c-di-GMP metabolizing enzymes found in this microbe. Importance We build on previous findings that suggest that P. aeruginosa utilizes c-di-GMP metabolizing enzymes to actively maintain a mature biofilm. Here, we explore how the diguanylate cyclase YfiN contributes to the regulation of biofilm maintenance during peroxide exposure. We find that mature P. aeruginosa biofilms require YfiN to synthesize c-di-GMP, regulate motility and to insure viability during peroxide stress. These findings provide further evidence that the modulation of c-di-GMP in response to environmental signals is an important mechanism by which biofilms are maintained.
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Li HQ, Shen YJ, Wang WL, Wang HT, Li H, Su JQ. Soil pH has a stronger effect than arsenic content on shaping plastisphere bacterial communities in soil. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 287:117339. [PMID: 34000668 DOI: 10.1016/j.envpol.2021.117339] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 05/04/2021] [Accepted: 05/06/2021] [Indexed: 06/12/2023]
Abstract
Microplastic (MP) pollution is widespread in various ecosystems and is colonized by microbes that form biofilms with compositions and functions. However, compared with aquatic environments, the soil environment has been poorly studied in terms of the taxonomic composition of microbial communities and the factors influencing the community structure of microbes in the plastisphere. In the present study, a microcosm experiment was conducted to investigate the plastisphere bacterial communities of MP (polyvinyl chloride, PVC) in soils with different pH (4.62, 6.5, and 7.46) and arsenic (As) contents (13 and 74 mg kg-1). Bacterial communities in the plastisphere were dominated by Proteobacteria and Firmicutes, with distinct compositions and structures compared with soil bacterial communities. Soil pH and As content significantly affected the plastisphere bacterial communities. Constrained analysis of principal coordinates and a structural equation model demonstrated that soil pH had a stronger influence on the dissimilarity and diversity of bacterial communities than did soil As content. Soil pH affected As speciation in soil and on MP. The concentration of dimethylarsinic acid (DMA) was significantly higher on MP than that in soil, indicating that As methylation occurred on MP. These results suggest that environmental fluctuations govern plastisphere bacterial communities with cascading effects on biogeochemical cycling of As in the soil ecosystems.
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Affiliation(s)
- Huan-Qin Li
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361102, China; Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, Fujian, 361021, China
| | - Ying-Jia Shen
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, 361102, China
| | - Wen-Lei Wang
- Fisheries College, Jimei University, Xiamen, 361021, China
| | - Hong-Tao Wang
- College of Environment and Planning, Henan University, Kaifeng, 475004, China
| | - Hu Li
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, Fujian, 361021, China
| | - Jian-Qiang Su
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, Fujian, 361021, China.
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49
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Evidence for biosurfactant-induced flow in corners and bacterial spreading in unsaturated porous media. Proc Natl Acad Sci U S A 2021; 118:2111060118. [PMID: 34531326 DOI: 10.1073/pnas.2111060118] [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] [Accepted: 07/29/2021] [Indexed: 12/31/2022] Open
Abstract
The spread of pathogenic bacteria in unsaturated porous media, where air and liquid coexist in pore spaces, is the major cause of soil contamination by pathogens, soft rot in plants, food spoilage, and many pulmonary diseases. However, visualization and fundamental understanding of bacterial transport in unsaturated porous media are currently lacking, limiting the ability to address the above contamination- and disease-related issues. Here, we demonstrate a previously unreported mechanism by which bacterial cells are transported in unsaturated porous media. We discover that surfactant-producing bacteria can generate flows along corners through surfactant production that changes the wettability of the solid surface. The corner flow velocity is on the order of several millimeters per hour, which is the same order of magnitude as bacterial swarming, one of the fastest known modes of bacterial surface translocation. We successfully predict the critical corner angle for bacterial corner flow to occur based on the biosurfactant-induced change in the contact angle of the bacterial solution on the solid surface. Furthermore, we demonstrate that bacteria can indeed spread by producing biosurfactants in a model soil, which consists of packed angular grains. In addition, we demonstrate that bacterial corner flow is controlled by quorum sensing, the cell-cell communication process that regulates biosurfactant production. Understanding this previously unappreciated bacterial transport mechanism will enable more accurate predictions of bacterial spreading in soil and other unsaturated porous media.
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50
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Mangioni SE, dell'Erba MG, Combi B. Structure formation in a conserved mass model of a set of individuals interacting with attractive and repulsive forces. Phys Rev E 2021; 104:014212. [PMID: 34412252 DOI: 10.1103/physreve.104.014212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 06/29/2021] [Indexed: 11/07/2022]
Abstract
We study a set of interacting individuals that conserve their total mass. In order to describe its dynamics we resort to mesoscopic equations of reaction diffusion including currents driven by attractive and repulsive forces. For the mass conservation we consider a linear response parameter that maintains the mass in the vicinity of a optimal value which is determined by the set. We use the reach and intensity of repulsive forces as control parameters. When sweeping a wide range of parameter space we find a great diversity of localized structures, stationary as well as other ones with cyclical and chaotic dynamics. We compare our results with real situations.
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Affiliation(s)
- Sergio E Mangioni
- IFIMAR (Universidad Nacional de Mar del Plata and CONICET), Deán Funes 3350, B7602AYL Mar del Plata, Argentina
| | - Matías G dell'Erba
- IFIMAR (Universidad Nacional de Mar del Plata and CONICET), Deán Funes 3350, B7602AYL Mar del Plata, Argentina
| | - Bruno Combi
- IFIMAR (Universidad Nacional de Mar del Plata and CONICET), Deán Funes 3350, B7602AYL Mar del Plata, Argentina
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