1
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Chai L, Zaburdaev V, Kolter R. How bacteria actively use passive physics to make biofilms. Proc Natl Acad Sci U S A 2024; 121:e2403842121. [PMID: 39264745 PMCID: PMC11459164 DOI: 10.1073/pnas.2403842121] [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] [Indexed: 09/14/2024] Open
Abstract
Modern molecular microbiology elucidates the organizational principles of bacterial biofilms via detailed examination of the interplay between signaling and gene regulation. A complementary biophysical approach studies the mesoscopic dependencies at the cellular and multicellular levels with a distinct focus on intercellular forces and mechanical properties of whole biofilms. Here, motivated by recent advances in biofilm research and in other, seemingly unrelated fields of biology and physics, we propose a perspective that links the biofilm, a dynamic multicellular organism, with the physical processes occurring in the extracellular milieu. Using Bacillus subtilis as an illustrative model organism, we specifically demonstrate how such a rationale explains biofilm architecture, differentiation, communication, and stress responses such as desiccation tolerance, metabolism, and physiology across multiple scales-from matrix proteins and polysaccharides to macroscopic wrinkles and water-filled channels.
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Affiliation(s)
- Liraz Chai
- Institute of Chemistry, Hebrew University of Jerusalem, Jerusalem9190401, Israel
- The Harvey M. Krueger Family Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem9190401, Israel
- Max Planck Queensland Centre, Queensland University of Technology, Brisbane, QLD4000, Australia
| | - Vasily Zaburdaev
- Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen91058, Germany
- Max-Planck-Zentrum für Physik und Medizin, Erlangen91058, Germany
| | - Roberto Kolter
- Department of Microbiology, Harvard Medical School, Boston, MA02115
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2
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Cheon J, Son J, Lim S, Jeong Y, Park JH, Mitchell RJ, Kim JU, Jeong J. Motile bacteria crossing liquid-liquid interfaces of an aqueous isotropic-nematic coexistence phase. SOFT MATTER 2024; 20:7313-7320. [PMID: 39248026 DOI: 10.1039/d4sm00766b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/10/2024]
Abstract
In nature, bacteria often swim in complex fluids, but our understanding of the interactions between bacteria and complex surroundings is still evolving. In this work, rod-like Bacillus subtilis swims in a quasi-2D environment with aqueous liquid-liquid interfaces, i.e., the isotropic-nematic coexistence phase of an aqueous chromonic liquid crystal. Focusing on the bacteria motion near and at the liquid-liquid interfaces, we collect and quantify bacterial trajectories ranging across the isotropic to the nematic phase. Despite its small magnitude, the interfacial tension of the order of 10 μN m-1 at the isotropic-nematic interface justifies our observations that bacteria swimming more perpendicular to the interface have a higher probability of crossing the interface. Our force-balance model, considering the interfacial tension, further predicts how the length and speed of the bacteria affect their crossing behaviors. Investigating how a phase change affects bacterial motion, we also find, as soon as the bacteria cross the interface and enter the nematic phase, they wiggle less, but faster, and that this occurs as the flagellar bundles aggregate within the nematic phase. Given the ubiquity of multi-phases in biological environments, our findings will help to understand active transport across various phases.
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Affiliation(s)
- Jiyong Cheon
- Department of Physics, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea.
| | - Joowang Son
- Department of Physics, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea.
| | - Sungbin Lim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Yundon Jeong
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Jung-Hoon Park
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Robert J Mitchell
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Jaeup U Kim
- Department of Physics, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea.
| | - Joonwoo Jeong
- Department of Physics, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea.
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3
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Squyres GR, Newman DK. Biofilms as more than the sum of their parts: lessons from developmental biology. Curr Opin Microbiol 2024; 82:102537. [PMID: 39241276 DOI: 10.1016/j.mib.2024.102537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2024] [Revised: 08/09/2024] [Accepted: 08/11/2024] [Indexed: 09/09/2024]
Abstract
Although our understanding of both bacterial cell physiology and the complex behaviors exhibited by bacterial biofilms is expanding rapidly, we cannot yet sum the behaviors of individual cells to understand or predict biofilm behavior. This is both because cell physiology in biofilms is different from planktonic growth and because cell behavior in biofilms is spatiotemporally patterned. We use developmental biology as a guide to examine this phenotypic patterning, discussing candidate cues that may encode spatiotemporal information and possible roles for phenotypic patterning in biofilms. We consider other questions that arise from the comparison between biofilm and eukaryotic development, including what defines normal biofilm development and the nature of biofilm cell types and fates. We conclude by discussing what biofilm development can tell us about developmental processes, emphasizing the additional challenges faced by bacteria in biofilm development compared with their eukaryotic counterparts.
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Affiliation(s)
- Georgia R Squyres
- Division of Biology and Biological Engineering, Caltech, Pasadena, CA 91125, USA
| | - Dianne K Newman
- Division of Biology and Biological Engineering, Caltech, Pasadena, CA 91125, USA; Division of Geological and Planetary Sciences, Caltech, Pasadena, CA 91125, USA.
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4
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Murugan PA, Sahu MK, Gupta MK, Sankar TS, Chandran S, Matheshwaran S. Deciphering the influence of NaCl on social behaviour of Bacillus subtilis. ROYAL SOCIETY OPEN SCIENCE 2024; 11:240822. [PMID: 39295915 PMCID: PMC11407874 DOI: 10.1098/rsos.240822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Revised: 08/09/2024] [Accepted: 08/12/2024] [Indexed: 09/21/2024]
Abstract
Various environmental signals, such as temperature, pH, nutrient levels, salt content and the presence of other microorganisms, can influence biofilm's development and dynamics. However, the innate mechanisms that govern at the molecular and cellular levels remain elusive. Here, we report the impact of physiologically relevant concentrations of NaCl on biofilm formation and the associated differences in an undomesticated natural isolate of Bacillus subtilis. NaCl exposure and its uptake by bacterial cells induced substantial changes in the architecture of pellicle biofilm and an upsurge in the expansion of biofilm colonies on agar surfaces. We have observed the upregulation of genes involved in motility and the downregulation of genes involved in the biosynthesis of extracellular matrix components through the transcription factor sigD, suggesting the possible underlying mechanisms. To further support these observations, we have used ΔsigD and ΔsrfAC null mutants, which showed compromised NaCl-induced effects. Our results indicate that NaCl induces a lifestyle shift in B. subtilis from a sessile biofilm state to an independent unicellular motile state. Overall, we present evidence that NaCl can reprogramme gene expression and alter cellular morphology and the state of cells to adapt to motility, which facilitates the expansion of bacterial colonies.
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Affiliation(s)
- Prem Anand Murugan
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India
| | - Muktesh Kumar Sahu
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India
| | - Manish Kumar Gupta
- Soft and Biological Matter Laboratory, Department of Physics, Indian Institute of Technology, Kanpur, India
| | - T Sabari Sankar
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, India
| | - Sivasurender Chandran
- Soft and Biological Matter Laboratory, Department of Physics, Indian Institute of Technology, Kanpur, India
| | - Saravanan Matheshwaran
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur, India
- Centre for Environmental Sciences and Engineering, Indian Institute of Technology, Kanpur, India
- Mehta Family Centre for Engineering in Medicine, Indian Institute of Technology, Kanpur, India
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5
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Gilhar O, Ben-Navi LR, Olender T, Aharoni A, Friedman J, Kolodkin-Gal I. Multigenerational inheritance drives symbiotic interactions of the bacterium Bacillus subtilis with its plant host. Microbiol Res 2024; 286:127814. [PMID: 38954993 DOI: 10.1016/j.micres.2024.127814] [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: 04/13/2024] [Revised: 06/04/2024] [Accepted: 06/18/2024] [Indexed: 07/04/2024]
Abstract
Bacillus subtilis is a beneficial bacterium that supports plant growth and protects plants from bacterial, fungal, and viral infections. Using a simplified system of B. subtilis and Arabidopsis thaliana interactions, we studied the fitness and transcriptome of bacteria detached from the root over generations of growth in LB medium. We found that bacteria previously associated with the root or exposed to its secretions had greater stress tolerance and were more competitive in root colonization than bacteria not previously exposed to the root. Furthermore, our transcriptome results provide evidence that plant secretions induce a microbial stress response and fundamentally alter signaling by the cyclic nucleotide c-di-AMP, a signature maintained by their descendants. The changes in cellular physiology due to exposure to plant exudates were multigenerational, as they allowed not only the bacterial cells that colonized a new plant but also their descendants to have an advance over naive competitors of the same species, while the overall plasticity of gene expression and rapid adaptation were maintained. These changes were hereditary but not permanent. Our work demonstrates a bacterial memory manifested by multigenerational reversible adaptation to plant hosts in the form of activation of the stressosome, which confers an advantage to symbiotic bacteria during competition.
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Affiliation(s)
- Omri Gilhar
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel; Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | | | - Tsviya Olender
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Asaph Aharoni
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Jonathan Friedman
- Department of Plant Pathology and Microbiology, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Ilana Kolodkin-Gal
- Scojen Institute for Synthetic Biology, Reichman University, Herzliya, Israel.
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6
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Rosazza T, Earl C, Eigentler L, Davidson FA, Stanley-Wall NR. Reciprocal sharing of extracellular proteases and extracellular matrix molecules facilitates Bacillus subtilis biofilm formation. Mol Microbiol 2024; 122:184-200. [PMID: 38922753 DOI: 10.1111/mmi.15288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 06/06/2024] [Accepted: 06/06/2024] [Indexed: 06/28/2024]
Abstract
Extracellular proteases are a class of public good that support growth of Bacillus subtilis when nutrients are in a polymeric form. Bacillus subtilis biofilm matrix molecules are another class of public good that are needed for biofilm formation and are prone to exploitation. In this study, we investigated the role of extracellular proteases in B. subtilis biofilm formation and explored interactions between different public good producer strains across various conditions. We confirmed that extracellular proteases support biofilm formation even when glutamic acid provides a freely available nitrogen source. Removal of AprE from the NCIB 3610 secretome adversely affects colony biofilm architecture, while sole induction of WprA activity into an otherwise extracellular protease-free strain is sufficient to promote wrinkle development within the colony biofilm. We found that changing the nutrient source used to support growth affected B. subtilis biofilm structure, hydrophobicity and architecture. We propose that the different phenotypes observed may be due to increased protease dependency for growth when a polymorphic protein presents the sole nitrogen source. We however cannot exclude that the phenotypic changes are due to alternative matrix molecules being made. Co-culture of biofilm matrix and extracellular protease mutants can rescue biofilm structure, yet reliance on extracellular proteases for growth influences population coexistence dynamics. Our findings highlight the intricate interplay between these two classes of public goods, providing insights into microbial social dynamics during biofilm formation across different ecological niches.
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Affiliation(s)
- Thibault Rosazza
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, UK
| | - Chris Earl
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, UK
| | - Lukas Eigentler
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, UK
- Mathematics, School of Science and Engineering, University of Dundee, Dundee, UK
| | - Fordyce A Davidson
- Mathematics, School of Science and Engineering, University of Dundee, Dundee, UK
| | - Nicola R Stanley-Wall
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, UK
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7
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Liu S, Li Y, Xu H, Kearns DB, Wu Y. Active interface bulging in Bacillus subtilis swarms promotes self-assembly and biofilm formation. Proc Natl Acad Sci U S A 2024; 121:e2322025121. [PMID: 39052827 PMCID: PMC11295035 DOI: 10.1073/pnas.2322025121] [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: 12/14/2023] [Accepted: 06/21/2024] [Indexed: 07/27/2024] Open
Abstract
Microbial communities such as biofilms are commonly found at interfaces. However, it is unclear how the physical environment of interfaces may contribute to the development and behavior of surface-associated microbial communities. Combining multimode imaging, single-cell tracking, and numerical simulations, here, we found that activity-induced interface bulging promotes colony biofilm formation in Bacillus subtilis swarms presumably via segregation and enrichment of sessile cells in the bulging area. Specifically, the diffusivity of passive particles is ~50% lower inside the bulging area than elsewhere, which enables a diffusion-trapping mechanism for self-assembly and may account for the enrichment of sessile cells. We also uncovered a quasilinear relation between cell speed and surface-packing density that underlies the process of active interface bulging. Guided by the speed-density relation, we demonstrated reversible formation of liquid bulges by manipulating the speed and local density of cells with light. Over the course of development, the active bulges turned into striped biofilm structures, which eventually give rise to a large-scale ridge pattern. Our findings reveal a unique physical mechanism of biofilm formation at air-solid interface, which is pertinent to engineering living materials and directed self-assembly in active fluids.
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Affiliation(s)
- Siyu Liu
- Department of Physics and Shenzhen Research Institute, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, People’s Republic of China
| | - Ye Li
- Department of Physics and Shenzhen Research Institute, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, People’s Republic of China
- Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong518055, China
| | - Haoran Xu
- Department of Physics and Shenzhen Research Institute, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, People’s Republic of China
| | - Daniel B. Kearns
- Department of Biology, Indiana University, Bloomington, IN47405-7005
| | - Yilin Wu
- Department of Physics and Shenzhen Research Institute, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, People’s Republic of China
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8
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Christian N, Burden D, Emam A, Brenk A, Sperber S, Kalu M, Cuadra G, Palazzolo D. Effects of E-Liquids and Their Aerosols on Biofilm Formation and Growth of Oral Commensal Streptococcal Communities: Effect of Cinnamon and Menthol Flavors. Dent J (Basel) 2024; 12:232. [PMID: 39195076 DOI: 10.3390/dj12080232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2024] [Revised: 07/11/2024] [Accepted: 07/19/2024] [Indexed: 08/29/2024] Open
Abstract
(1) Background: The rise in electronic cigarette (E-cigarette) popularity, especially among adolescents, has prompted research to investigate potential effects on health. Although much research has been carried out on the effect on lung health, the first site exposed to vaping-the oral cavity-has received relatively little attention. The aims of this study were twofold: to examine the effects of E-liquids on the viability and hydrophobicity of oral commensal streptococci, and the effects of E-cigarette-generated aerosols on the biomass and viability of oral commensal streptococci. (2) Methods: Quantitative and confocal biofilm analysis, live-dead staining, and hydrophobicity assays were used to determine the effect on oral commensal streptococci after exposure to E-liquids and/or E-cigarette-generated aerosols. (3) Results: E-liquids and flavors have a bactericidal effect on multispecies oral commensal biofilms and increase the hydrophobicity of oral commensal streptococci. Flavorless and some flavored E-liquid aerosols have a bactericidal effect on oral commensal biofilms while having no effect on overall biomass. (4) Conclusions: These results indicate that E-liquids/E-cigarette-generated aerosols alter the chemical interactions and viability of oral commensal streptococci. Consequently, the use of E-cigarettes has the potential to alter the status of disease and health in the oral cavity and, by extension, affect systemic health.
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Affiliation(s)
- Nicole Christian
- Biology Department, Muhlenberg College, Allentown, PA 18104, USA
- School of Dentistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Daniel Burden
- Biology Department, Muhlenberg College, Allentown, PA 18104, USA
- School of Dental Medicine, University of Colorado, Aurora, CO 80045, USA
| | - Alexander Emam
- Biology Department, Muhlenberg College, Allentown, PA 18104, USA
| | - Alvin Brenk
- Debusk College of Osteopathic Medicine, Lincoln Memorial University, Harrogate, TN 37752, USA
- Yale New Haven Hospital, New Haven, CT 06510, USA
| | - Sarah Sperber
- Debusk College of Osteopathic Medicine, Lincoln Memorial University, Harrogate, TN 37752, USA
| | - Michael Kalu
- Debusk College of Osteopathic Medicine, Lincoln Memorial University, Harrogate, TN 37752, USA
| | - Giancarlo Cuadra
- Biology Department, Muhlenberg College, Allentown, PA 18104, USA
| | - Dominic Palazzolo
- Debusk College of Osteopathic Medicine, Lincoln Memorial University, Harrogate, TN 37752, USA
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9
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Xue Y, Yu C, Ouyang H, Huang J, Kang X. Uncovering the Molecular Composition and Architecture of the Bacillus subtilis Biofilm via Solid-State NMR Spectroscopy. J Am Chem Soc 2024; 146:11906-11923. [PMID: 38629727 DOI: 10.1021/jacs.4c00889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
The complex and dynamic compositions of biofilms, along with their sophisticated structural assembly mechanisms, endow them with exceptional capabilities to thrive in diverse conditions that are typically unfavorable for individual cells. Characterizing biofilms in their native state is significantly challenging due to their intrinsic complexities and the limited availability of noninvasive techniques. Here, we utilized solid-state nuclear magnetic resonance (NMR) spectroscopy to analyze Bacillus subtilis biofilms in-depth. Our data uncover a dynamically distinct organization within the biofilm: a dominant, hydrophilic, and mobile framework interspersed with minor, rigid cores of limited water accessibility. In these heterogeneous rigid cores, the major components are largely self-assembled. TasA fibers, the most robust elements, further provide a degree of mechanical support for the cell aggregates and some lipid vesicles. Notably, rigid cell aggregates can persist even without the major extracellular polymeric substance (EPS) polymers, although this leads to slight variations in their rigidity and water accessibility. Exopolysaccharides are exclusively present in the mobile domain, playing a pivotal role in its water retention property. Specifically, all water molecules are tightly bound within the biofilm matrix. These findings reveal a dual-layered defensive strategy within the biofilm: a diffusion barrier through limited water mobility in the mobile phase and a physical barrier posed by limited water accessibility in the rigid phase. Complementing these discoveries, our comprehensive, in situ compositional analysis is not only essential for delineating the sophisticated biofilm architecture but also reveals the presence of alternative genetic mechanisms for synthesizing exopolysaccharides beyond the known pathway.
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Affiliation(s)
- Yi Xue
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Chenjie Yu
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Han Ouyang
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Jiaofang Huang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Xue Kang
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, Zhejiang 315211, China
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10
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Postek W, Staśkiewicz K, Lilja E, Wacław B. Substrate geometry affects population dynamics in a bacterial biofilm. Proc Natl Acad Sci U S A 2024; 121:e2315361121. [PMID: 38621130 PMCID: PMC11047097 DOI: 10.1073/pnas.2315361121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 03/11/2024] [Indexed: 04/17/2024] Open
Abstract
Biofilms inhabit a range of environments, such as dental plaques or soil micropores, often characterized by noneven surfaces. However, the impact of surface irregularities on the population dynamics of biofilms remains elusive, as most experiments are conducted on flat surfaces. Here, we show that the shape of the surface on which a biofilm grows influences genetic drift and selection within the biofilm. We culture Escherichia coli biofilms in microwells with a corrugated bottom surface and observe the emergence of clonal sectors whose size corresponds to that of the corrugations, despite no physical barrier separating different areas of the biofilm. The sectors are remarkably stable and do not invade each other; we attribute this stability to the characteristics of the velocity field within the biofilm, which hinders mixing and clonal expansion. A microscopically detailed computer model fully reproduces these findings and highlights the role of mechanical interactions such as adhesion and friction in microbial evolution. The model also predicts clonal expansion to be limited even for clones with a significant growth advantage-a finding which we confirm experimentally using a mixture of antibiotic-sensitive and antibiotic-resistant mutants in the presence of sublethal concentrations of the antibiotic rifampicin. The strong suppression of selection contrasts sharply with the behavior seen in range expansion experiments in bacterial colonies grown on agar. Our results show that biofilm population dynamics can be affected by patterning the surface and demonstrate how a better understanding of the physics of bacterial growth can be used to control microbial evolution.
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Affiliation(s)
- Witold Postek
- Dioscuri Centre for Physics and Chemistry of Bacteria, Institute of Physical Chemistry, Polish Academy of Sciences, Warszawa01-224, Poland
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA02142
| | - Klaudia Staśkiewicz
- Dioscuri Centre for Physics and Chemistry of Bacteria, Institute of Physical Chemistry, Polish Academy of Sciences, Warszawa01-224, Poland
| | - Elin Lilja
- Dioscuri Centre for Physics and Chemistry of Bacteria, Institute of Physical Chemistry, Polish Academy of Sciences, Warszawa01-224, Poland
| | - Bartłomiej Wacław
- Dioscuri Centre for Physics and Chemistry of Bacteria, Institute of Physical Chemistry, Polish Academy of Sciences, Warszawa01-224, Poland
- School of Physics and Astronomy, The University of Edinburgh, EdinburghEH9 3FD, United Kingdom
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11
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Weaver AA, Jia J, Cutri AR, Madukoma CS, Vaerewyck CM, Bohn PW, Shrout JD. Alkyl quinolones mediate heterogeneous colony biofilm architecture that improves community-level survival. J Bacteriol 2024; 206:e0009524. [PMID: 38564677 PMCID: PMC11025328 DOI: 10.1128/jb.00095-24] [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: 03/05/2024] [Accepted: 03/11/2024] [Indexed: 04/04/2024] Open
Abstract
Bacterial communities exhibit complex self-organization that contributes to their survival. To better understand the molecules that contribute to transforming a small number of cells into a heterogeneous surface biofilm community, we studied acellular aggregates, structures seen by light microscopy in Pseudomonas aeruginosa colony biofilms using light microscopy and chemical imaging. These structures differ from cellular aggregates, cohesive clusters of cells important for biofilm formation, in that they are visually distinct from cells using light microscopy and are reliant on metabolites for assembly. To investigate how these structures benefit a biofilm community we characterized three recurrent types of acellular aggregates with distinct geometries that were each abundant in specific areas of these biofilms. Alkyl quinolones (AQs) were essential for the formation of all aggregate types with AQ signatures outside the aggregates below the limit of detection. These acellular aggregates spatially sequester AQs and differentiate the biofilm space. However, the three types of aggregates showed differing properties in their size, associated cell death, and lipid content. The largest aggregate type co-localized with spatially confined cell death that was not mediated by Pf4 bacteriophage. Biofilms lacking AQs were absent of localized cell death but exhibited increased, homogeneously distributed cell death. Thus, these AQ-rich aggregates regulate metabolite accessibility, differentiate regions of the biofilm, and promote survival in biofilms.IMPORTANCEPseudomonas aeruginosa is an opportunistic pathogen with the ability to cause infection in the immune-compromised. It is well established that P. aeruginosa biofilms exhibit resilience that includes decreased susceptibility to antimicrobial treatment. This work examines the self-assembled heterogeneity in biofilm communities studying acellular aggregates, regions of condensed matter requiring alkyl quinolones (AQs). AQs are important to both virulence and biofilm formation. Aggregate structures described here spatially regulate the accessibility of these AQs, differentiate regions of the biofilm community, and despite their association with autolysis, correlate with improved P. aeruginosa colony biofilm survival.
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Affiliation(s)
- Abigail A. Weaver
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Jin Jia
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Allison R. Cutri
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Chinedu S. Madukoma
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Catherine M. Vaerewyck
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Paul W. Bohn
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana, USA
| | - Joshua D. Shrout
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
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12
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Carreira de Paula J, García Olmedo P, Gómez-Moracho T, Buendía-Abad M, Higes M, Martín-Hernández R, Osuna A, de Pablos LM. Promastigote EPS secretion and haptomonad biofilm formation as evolutionary adaptations of trypanosomatid parasites for colonizing honeybee hosts. NPJ Biofilms Microbiomes 2024; 10:27. [PMID: 38514634 PMCID: PMC10957890 DOI: 10.1038/s41522-024-00492-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 02/22/2024] [Indexed: 03/23/2024] Open
Abstract
Bees are major pollinators involved in the maintenance of all terrestrial ecosystems. Biotic and abiotic factors placing these insects at risk is a research priority for ecological and agricultural sustainability. Parasites are one of the key players of this global decline and the study of their mechanisms of action is essential to control honeybee colony losses. Trypanosomatid parasites and particularly the Lotmaria passim are widely spread in honeybees, however their lifestyle is poorly understood. In this work, we show how these parasites are able to differentiate into a new parasitic lifestyle: the trypanosomatid biofilms. Using different microscopic techniques, we demonstrated that the secretion of Extracellular Polymeric Substances by free-swimming unicellular promastigote forms is a prerequisite for the generation and adherence of multicellular biofilms to solid surfaces in vitro and in vivo. Moreover, compared to human-infective trypanosomatid parasites our study shows how trypanosomatid parasites of honeybees increases their resistance and thus resilience to drastic changes in environmental conditions such as ultralow temperatures and hypoosmotic shock, which would explain their success thriving within or outside their hosts. These results set up the basis for the understanding of the success of this group of parasites in nature and to unveil the impact of such pathogens in honeybees, a keystones species in most terrestrial ecosystems.
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Affiliation(s)
- Jéssica Carreira de Paula
- Department of Parasitology, Biochemical and Molecular Parasitology Group CTS-183, University of Granada, Granada, Spain
- Institute of Biotechnology, University of Granada, Granada, Spain
| | - Pedro García Olmedo
- Department of Parasitology, Biochemical and Molecular Parasitology Group CTS-183, University of Granada, Granada, Spain
- Institute of Biotechnology, University of Granada, Granada, Spain
| | - Tamara Gómez-Moracho
- Department of Parasitology, Biochemical and Molecular Parasitology Group CTS-183, University of Granada, Granada, Spain
- Institute of Biotechnology, University of Granada, Granada, Spain
| | - María Buendía-Abad
- Laboratorio de Patología Apícola, Centro de Investigación Apícola y Agroambiental (CIAPA), IRIAF - Instituto Regional de Investigación y Desarrollo Agroalimentario y Forestal, Consejería de Agricultura de la Junta de Comunidades de Castilla-La Mancha, Marchamalo, Spain
- Instituto de Recursos Humanos para la Ciencia y la Tecnología, Fundación Parque Científico y Tecnológico de Castilla-La Mancha, 02006, Albacete, Spain
| | - Mariano Higes
- Laboratorio de Patología Apícola, Centro de Investigación Apícola y Agroambiental (CIAPA), IRIAF - Instituto Regional de Investigación y Desarrollo Agroalimentario y Forestal, Consejería de Agricultura de la Junta de Comunidades de Castilla-La Mancha, Marchamalo, Spain
- Instituto de Recursos Humanos para la Ciencia y la Tecnología, Fundación Parque Científico y Tecnológico de Castilla-La Mancha, 02006, Albacete, Spain
| | - Raquel Martín-Hernández
- Laboratorio de Patología Apícola, Centro de Investigación Apícola y Agroambiental (CIAPA), IRIAF - Instituto Regional de Investigación y Desarrollo Agroalimentario y Forestal, Consejería de Agricultura de la Junta de Comunidades de Castilla-La Mancha, Marchamalo, Spain
- Instituto de Recursos Humanos para la Ciencia y la Tecnología, Fundación Parque Científico y Tecnológico de Castilla-La Mancha, 02006, Albacete, Spain
| | - Antonio Osuna
- Department of Parasitology, Biochemical and Molecular Parasitology Group CTS-183, University of Granada, Granada, Spain
- Institute of Biotechnology, University of Granada, Granada, Spain
| | - Luis Miguel de Pablos
- Department of Parasitology, Biochemical and Molecular Parasitology Group CTS-183, University of Granada, Granada, Spain.
- Institute of Biotechnology, University of Granada, Granada, Spain.
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13
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Cao X, Zhang T, Tao C, Ren Y, Wang X. A new method: Characterize and quantify biofilm wrinkles by UNet and Sholl Analysis. Biosystems 2024; 237:105131. [PMID: 38286325 DOI: 10.1016/j.biosystems.2024.105131] [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: 10/16/2023] [Revised: 01/26/2024] [Accepted: 01/26/2024] [Indexed: 01/31/2024]
Abstract
The wrinkles on the biofilm contain a lot of information about biofilm growth, so it is essential to characterize and quantify these wrinkles from the original microscopic images to discover more rules governing the biofilm morphology evolution. However, the existing methods to extract the wrinkles are time-consuming, error-prone, and require manual calibration. We propose a new system: using a deep learning method - UNet to identify the biofilm wrinkles in the original experimental images, which can achieve fast and accurate extraction of wrinkles on biofilms. Combining the result of UNet and medical neuron analysis method - Sholl Analysis, we can easily characterize and quantity the B. subtilis biofilm wrinkles. We proposed new characterization parameters such as wrinkle density, wrinkle length, and wrinkle projection area, which can precisely partition the biofilm surface wrinkles into different regions from the biofilm center to the edge, different regions correspond to different growth stages. Our system can be applied to study biofilms growing in different kinds of environments and to study the biofilm growth mechanisms.
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Affiliation(s)
- Xiaolei Cao
- School of Mechanical Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Tiecheng Zhang
- School of Mechanical Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Cong Tao
- School of Mechanical Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yifan Ren
- 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, 02138, Cambridge, MA, USA.
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14
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Ezeh CK, Dibua MEU. Anti-biofilm, drug delivery and cytotoxicity properties of dendrimers. ADMET AND DMPK 2024; 12:239-267. [PMID: 38720923 PMCID: PMC11075165 DOI: 10.5599/admet.1917] [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: 06/01/2023] [Revised: 01/24/2023] [Indexed: 05/12/2024] Open
Abstract
Background and purpose Treatments using antimicrobial agents have faced many difficulties as a result of biofilm formation by pathogenic microorganisms. The biofilm matrix formed by these microorganisms prevents antimicrobial agents from penetrating the interior where they can exact their activity effectively. Additionally, extracellular polymeric molecules associated with biofilm surfaces can absorb antimicrobial compounds, lowering their bioavailability. This problem has resulted in the quest for alternative treatment protocols, and the development of nanomaterials and devices through nanotechnology has recently been on the rise. Research approach The literature on dendrimers was searched for in databases such as Google Scholar, PubMed, and ScienceDirect. Key results As a nanomaterial, dendrimers have found useful applications as a drug delivery vehicle for antimicrobial agents against biofilm-mediated infections to circumvent these defense mechanisms. The distinctive properties of dendrimers, such as multi-valency, biocompatibility, high water solubility, non-immunogenicity, and biofilm matrix-/cell membrane fusogenicity (ability to merge with intracellular membrane or other proteins), significantly increase the efficacy of antimicrobial agents and reduce the likelihood of recurring infections. Conclusion This review outlines the current state of dendrimer carriers for biofilm treatments, provides examples of their real-world uses, and examines potential drawbacks.
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Affiliation(s)
- Christian K. Ezeh
- University of Nigeria, Department of Microbiology, Nsukka, Enugu State, Nigeria
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15
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Ching C, Brychcy M, Nguyen B, Muller P, Pearson AR, Downs M, Regan S, Isley B, Fowle W, Chai Y, Godoy VG. RecA levels modulate biofilm development in Acinetobacter baumannii. Mol Microbiol 2024; 121:196-212. [PMID: 37918886 DOI: 10.1111/mmi.15188] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 10/06/2023] [Accepted: 10/17/2023] [Indexed: 11/04/2023]
Abstract
Infections caused by Acinetobacter baumannii, a Gram-negative opportunistic pathogen, are difficult to eradicate due to the bacterium's propensity to quickly gain antibiotic resistances and form biofilms, a protective bacterial multicellular community. The A. baumannii DNA damage response (DDR) mediates the antibiotic resistance acquisition and regulates RecA in an atypical fashion; both RecALow and RecAHigh cell types are formed in response to DNA damage. The findings of this study demonstrate that the levels of RecA can influence formation and dispersal of biofilms. RecA loss results in surface attachment and prominent biofilms, while elevated RecA leads to diminished attachment and dispersal. These findings suggest that the challenge to treat A. baumannii infections may be explained by the induction of the DDR, common during infection, as well as the delicate balance between maintaining biofilms in low RecA cells and promoting mutagenesis and dispersal in high RecA cells. This study underscores the importance of understanding the fundamental biology of bacteria to develop more effective treatments for infections.
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Affiliation(s)
- Carly Ching
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Merlin Brychcy
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Brian Nguyen
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Paul Muller
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | | | - Margaret Downs
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Samuel Regan
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Breanna Isley
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - William Fowle
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Yunrong Chai
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
| | - Veronica G Godoy
- Department of Biology, Northeastern University, Boston, Massachusetts, USA
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16
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Romero-Montero A, Melgoza-Ramírez LJ, Ruíz-Aguirre JA, Chávez-Santoscoy A, Magaña JJ, Cortés H, Leyva-Gómez G, Del Prado-Audelo ML. Essential-Oils-Loaded Biopolymeric Nanoparticles as Strategies for Microbial and Biofilm Control: A Current Status. Int J Mol Sci 2023; 25:82. [PMID: 38203252 PMCID: PMC10778842 DOI: 10.3390/ijms25010082] [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: 11/09/2023] [Revised: 12/01/2023] [Accepted: 12/06/2023] [Indexed: 01/12/2024] Open
Abstract
The emergence of bacterial strains displaying resistance to the currently available antibiotics is a critical global concern. These resilient bacteria can form biofilms that play a pivotal role in the failure of bacterial infection treatments as antibiotics struggle to penetrate all biofilm regions. Consequently, eradicating bacteria residing within biofilms becomes considerably more challenging than their planktonic counterparts, leading to persistent and chronic infections. Among various approaches explored, essential oils loaded in nanoparticles based on biopolymers have emerged, promising strategies that enhance bioavailability and biological activities, minimize side effects, and control release through regulated pharmacokinetics. Different available reviews analyze nanosystems and essential oils; however, usually, their main goal is the analysis of their antimicrobial properties, and progress in biofilm combat is rarely discussed, or it is not the primary objective. This review aims to provide a global vision of biofilm conformation and describes mechanisms of action attributed to each EO. Furthermore, we present a comprehensive overview of the latest developments in biopolymeric nanoparticles research, especially in chitosan- and zein-based nanosystems, targeting multidrug-resistant bacteria in both their sessile and biofilm forms, which will help to design precise strategies for combating biofilms.
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Affiliation(s)
- Alejandra Romero-Montero
- Departamento de Farmacia, Facultad de Química, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (A.R.-M.); (G.L.-G.)
| | - Luis Javier Melgoza-Ramírez
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Mexico City 14380, Mexico; (L.J.M.-R.); (J.A.R.-A.); (J.J.M.)
| | - Jesús Augusto Ruíz-Aguirre
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Mexico City 14380, Mexico; (L.J.M.-R.); (J.A.R.-A.); (J.J.M.)
| | - Alejandra Chávez-Santoscoy
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Campus Monterrey, Ave. Eugenio Garza Sada 2501 Sur, Monterrey 64849, Mexico;
| | - Jonathan Javier Magaña
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Mexico City 14380, Mexico; (L.J.M.-R.); (J.A.R.-A.); (J.J.M.)
- Laboratorio de Medicina Genómica, Departamento de Genómica, Instituto Nacional de Rehabilitación Luis Guillermo Ibarra Ibarra, Mexico City 14389, Mexico;
| | - Hernán Cortés
- Laboratorio de Medicina Genómica, Departamento de Genómica, Instituto Nacional de Rehabilitación Luis Guillermo Ibarra Ibarra, Mexico City 14389, Mexico;
| | - Gerardo Leyva-Gómez
- Departamento de Farmacia, Facultad de Química, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (A.R.-M.); (G.L.-G.)
| | - María Luisa Del Prado-Audelo
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Mexico City 14380, Mexico; (L.J.M.-R.); (J.A.R.-A.); (J.J.M.)
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17
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Dergham Y, Le Coq D, Bridier A, Sanchez-Vizuete P, Jbara H, Deschamps J, Hamze K, Yoshida KI, Noirot-Gros MF, Briandet R. Bacillus subtilis NDmed, a model strain for biofilm genetic studies. Biofilm 2023; 6:100152. [PMID: 37694162 PMCID: PMC10485040 DOI: 10.1016/j.bioflm.2023.100152] [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: 03/27/2023] [Revised: 06/20/2023] [Accepted: 08/27/2023] [Indexed: 09/12/2023] Open
Abstract
The Bacillus subtilis strain NDmed was isolated from an endoscope washer-disinfector in a medical environment. NDmed can form complex macrocolonies with highly wrinkled architectural structures on solid medium. In static liquid culture, it produces thick pellicles at the interface with air as well as remarkable highly protruding ''beanstalk-like'' submerged biofilm structures at the solid surface. Since these mucoid submerged structures are hyper-resistant to biocides, NDmed has the ability to protect pathogens embedded in mixed-species biofilms by sheltering them from the action of these agents. Additionally, this non-domesticated and highly biofilm forming strain has the propensity of being genetically manipulated. Due to all these properties, the NDmed strain becomes a valuable model for the study of B. subtilis biofilms. This review focuses on several studies performed with NDmed that have highlighted the sophisticated genetic dynamics at play during B. subtilis biofilm formation. Further studies in project using modern molecular tools of advanced technologies with this strain, will allow to deepen our knowledge on the emerging properties of multicellular bacterial life.
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Affiliation(s)
- Yasmine Dergham
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350, Jouy-en-Josas, France
- Lebanese University, Faculty of Science, 1003 Beirut, Lebanon
| | - Dominique Le Coq
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350, Jouy-en-Josas, France
- Université Paris-Saclay, Centre National de la Recherche Scientifique (CNRS), INRAE, AgroParisTech, Micalis Institute, 78350, Jouy-en-Josas, France
| | - Arnaud Bridier
- Fougères Laboratory, Antibiotics, Biocides, Residues and Resistance Unit, Anses, 35300, Fougères, France
| | - Pilar Sanchez-Vizuete
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350, Jouy-en-Josas, France
| | - Hadi Jbara
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350, Jouy-en-Josas, France
| | - Julien Deschamps
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350, Jouy-en-Josas, France
| | - Kassem Hamze
- Lebanese University, Faculty of Science, 1003 Beirut, Lebanon
| | - Ken-ichi Yoshida
- Department of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657-8501, Japan
| | | | - Romain Briandet
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350, Jouy-en-Josas, France
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18
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Auria E, Deschamps J, Briandet R, Dupuy B. Extracellular succinate induces spatially organized biofilm formation in Clostridioides difficile. Biofilm 2023; 5:100125. [PMID: 37214349 PMCID: PMC10192414 DOI: 10.1016/j.bioflm.2023.100125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 04/18/2023] [Accepted: 04/19/2023] [Indexed: 05/24/2023] Open
Abstract
Clostridioides difficile infection associated to gut microbiome dysbiosis is the leading cause for nosocomial diarrhea. The ability of C. difficile to form biofilms has been progressively linked to its pathogenesis as well as its persistence in the gut. Although C. difficile has been reported to form biofilms in an increasing number of conditions, little is known about how these biofilms are formed in the gut and what factors may trigger their formation. Here we report that succinate, a metabolite abundantly produced by the dysbiotic gut microbiota, induces in vitro biofilm formation of C. difficile strains. We characterized the morphology and spatial composition of succinate-induced biofilms, and compared to non-induced or deoxycholate (DCA) induced biofilms. Biofilms induced by succinate are significantly thicker, structurally more complex, and poorer in proteins and exopolysaccharides (EPS). We then applied transcriptomics and genetics to characterize the early stages of succinate-induced biofilm formation and we showed that succinate-induced biofilm results from major metabolic shifts and cell-wall composition changes. Similar to DCA-induced biofilms, biofilms induced by succinate depend on the presence of a rapidly metabolized sugar. Finally, although succinate can be consumed by the bacteria, we found that the extracellular succinate is in fact responsible for the induction of biofilm formation through complex regulation involving global metabolic regulators and the osmotic stress response. Thus, our work suggests that as a gut signal, succinate may drive biofilm formation and help persistence of C. difficile in the gut, increasing the risk of relapse.
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Affiliation(s)
- Emile Auria
- Institut Pasteur, Université Paris-Cité, UMR-CNRS 6047, Laboratoire Pathogenèse des Bactéries Anaérobies, F-75015, Paris, France
| | - Julien Deschamps
- Institut Micalis, INRAE, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Romain Briandet
- Institut Micalis, INRAE, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Bruno Dupuy
- Institut Pasteur, Université Paris-Cité, UMR-CNRS 6047, Laboratoire Pathogenèse des Bactéries Anaérobies, F-75015, Paris, France
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19
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Dergham Y, Le Coq D, Nicolas P, Bidnenko E, Dérozier S, Deforet M, Huillet E, Sanchez-Vizuete P, Deschamps J, Hamze K, Briandet R. Direct comparison of spatial transcriptional heterogeneity across diverse Bacillus subtilis biofilm communities. Nat Commun 2023; 14:7546. [PMID: 37985771 PMCID: PMC10661151 DOI: 10.1038/s41467-023-43386-w] [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: 01/09/2023] [Accepted: 11/08/2023] [Indexed: 11/22/2023] Open
Abstract
Bacillus subtilis can form various types of spatially organised communities on surfaces, such as colonies, pellicles and submerged biofilms. These communities share similarities and differences, and phenotypic heterogeneity has been reported for each type of community. Here, we studied spatial transcriptional heterogeneity across the three types of surface-associated communities. Using RNA-seq analysis of different regions or populations for each community type, we identified genes that are specifically expressed within each selected population. We constructed fluorescent transcriptional fusions for 17 of these genes, and observed their expression in submerged biofilms using time-lapse confocal laser scanning microscopy (CLSM). We found mosaic expression patterns for some genes; in particular, we observed spatially segregated cells displaying opposite regulation of carbon metabolism genes (gapA and gapB), indicative of distinct glycolytic or gluconeogenic regimes coexisting in the same biofilm region. Overall, our study provides a direct comparison of spatial transcriptional heterogeneity, at different scales, for the three main models of B. subtilis surface-associated communities.
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Affiliation(s)
- Yasmine Dergham
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
- Lebanese University, Faculty of Science, Beirut, Lebanon
| | - Dominique Le Coq
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
- Université Paris-Saclay, Centre National de la Recherche Scientifique (CNRS), INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | - Pierre Nicolas
- Université Paris-Saclay, INRAE, MAIAGE, Jouy-en-Josas, France
| | - Elena Bidnenko
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | - Sandra Dérozier
- Université Paris-Saclay, INRAE, MAIAGE, Jouy-en-Josas, France
| | - Maxime Deforet
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, Laboratoire Jean Perrin, Paris, France
| | - Eugénie Huillet
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | - Pilar Sanchez-Vizuete
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | - Julien Deschamps
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France
| | - Kassem Hamze
- Lebanese University, Faculty of Science, Beirut, Lebanon.
| | - Romain Briandet
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France.
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20
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Li X, Kong R, Wang J, Wu J, Wang X. Matrix Producing Cells Induce the Morphological Difference in the Bacillus subtilis Biofilm. Indian J Microbiol 2023; 63:197-207. [PMID: 37325022 PMCID: PMC10267082 DOI: 10.1007/s12088-023-01073-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Accepted: 02/24/2023] [Indexed: 03/09/2023] Open
Abstract
There is a 'coffee ring' in the Bacillus subtilis biofilm center, and the colony biofilm morphologies are distinct inside and outside the 'coffee ring'. In this paper, we study this morphological difference and explain the reasons of the 'coffee ring' formation and further the causes to the morphological variation. We developed a quantitative method to characterize the surface morphology, the outer area is thicker than the inner area of the 'coffee ring', and the thickness amplitude in outer area is larger than inner area of the 'coffee ring'. We adopt a logistic growth model to obtain how the environmental resistance influence the colony biofilm thickness. Dead cells provide gaps for stress release and make folds formation in colony biofilm. we developed a technique for optical imaging and matching cells with the BRISK algorithm to capture the distribution and movement of motile cells and matrix producing cells in the colony biofilm. Matrix producing cells are mainly distribute in the outside of the 'coffee ring', and the extracellular matrix (ECM) prevents the motile cells moving outward from center. Motile cells mainly locate inside the ring, a small amount of dead motile cells outside the 'coffee ring' give rise to radial folds formation. There are no ECM blocking cell movements inside the ring, which result in uniform folds formation. The distribution of ECM and different phenotypes lead to the formation of the 'coffee ring', which is verified by using eps and flagellar mutants.
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Affiliation(s)
- 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
| | - Jin Wu
- 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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21
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Wang Y, Li L, Zhao D, Zhou W, Chen L, Su G, Zhang Z, Liu T. Surface patterns of mortar plates influence Spirulina platensis biofilm attached cultivation: Experiment and modeling. ALGAL RES 2023. [DOI: 10.1016/j.algal.2023.103079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2023]
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22
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Zhou P, Ding L, Yan Y, Wang Y, Su B. Recent advances in label-free imaging of cell-matrix adhesions. Chem Commun (Camb) 2023; 59:2341-2351. [PMID: 36744880 DOI: 10.1039/d2cc06499e] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Cell-matrix adhesions play an essential role in mediating and regulating many biological processes. The adhesion receptors, typically transmembrane integrins, provide dynamic correlations between intracellular environments and extracellular matrixes (ECMs) by bi-directional signaling. In-depth investigations of cell-matrix adhesion and integrin-mediated cell adhesive force are of great significance in biology and medicine. The emergence of advanced imaging techniques and principles has facilitated the understanding of the molecular composition and structure dynamics of cell-matrix adhesions, especially the label-free imaging methods that can be used to study living cell dynamics without immunofluorescence staining. This highlight article aims to give an overview of recent developments in imaging cell-matrix adhesions in a label-free manner. Electrochemiluminescence microscopy (ECLM) and surface plasmon resonance microscopy (SPRM) are briefly introduced and their applications in imaging analysis of cell-matrix adhesions are summarized. Then we highlight the advances in mapping cell-matrix adhesion force based on molecular tension probes and fluorescence microscopy (collectively termed as MTFM). The biomaterials including polyethylene glycol (PEG), peptides and DNA for constructing tension probes in MTFM are summarized. Finally, the outlook and perspectives on the further developments of cell-matrix adhesion imaging are presented.
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Affiliation(s)
- Ping Zhou
- Key Laboratory of Excited-State Materials of Zhejiang Province, Institute of Analytical Chemistry, Department of Chemistry, Zhejiang University, Hangzhou 310058, China.
| | - Lurong Ding
- Key Laboratory of Excited-State Materials of Zhejiang Province, Institute of Analytical Chemistry, Department of Chemistry, Zhejiang University, Hangzhou 310058, China.
| | - Yajuan Yan
- Key Laboratory of Excited-State Materials of Zhejiang Province, Institute of Analytical Chemistry, Department of Chemistry, Zhejiang University, Hangzhou 310058, China.
| | - Yafeng Wang
- Key Laboratory of Excited-State Materials of Zhejiang Province, Institute of Analytical Chemistry, Department of Chemistry, Zhejiang University, Hangzhou 310058, China.
| | - Bin Su
- Key Laboratory of Excited-State Materials of Zhejiang Province, Institute of Analytical Chemistry, Department of Chemistry, Zhejiang University, Hangzhou 310058, China.
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23
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Bera P, Wasim A, Ghosh P. A mechanistic understanding of microcolony morphogenesis: coexistence of mobile and sessile aggregates. SOFT MATTER 2023; 19:1034-1045. [PMID: 36648295 DOI: 10.1039/d2sm01365g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Most bacteria in the natural environment self-organize into collective phases such as cell clusters, swarms, patterned colonies, or biofilms. Several intrinsic and extrinsic factors, such as growth, motion, and physicochemical interactions, govern the occurrence of different phases and their coexistence. Hence, predicting the conditions under which a collective phase emerges due to individual-level interactions is crucial. Here we develop a particle-based biophysical model of bacterial cells and self-secreted extracellular polymeric substances (EPS) to decipher the interplay of growth, motility-mediated dispersal, and mechanical interactions during microcolony morphogenesis. We show that the microcolony dynamics and architecture significantly vary depending upon the heterogeneous EPS production. In particular, microcolony shows the coexistence of both motile and sessile aggregates rendering a transition towards biofilm formation. We identified that the interplay of differential dispersion and the mechanical interactions among the components of the colony determines the fate of the colony morphology. Our results provide a significant understanding of the mechano-self-regulation during biofilm morphogenesis and open up possibilities of designing experiments to test the predictions.
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Affiliation(s)
- Palash Bera
- Tata Institute of Fundamental Research Hyderabad, Telangana, 500046, India
| | - Abdul Wasim
- Tata Institute of Fundamental Research Hyderabad, Telangana, 500046, India
| | - Pushpita Ghosh
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Kerala, 695551, India.
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24
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Römling U. Is biofilm formation intrinsic to the origin of life? Environ Microbiol 2023; 25:26-39. [PMID: 36655713 PMCID: PMC10086821 DOI: 10.1111/1462-2920.16179] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 08/19/2022] [Indexed: 01/21/2023]
Abstract
Biofilms are multicellular, often surface-associated, communities of autonomous cells. Their formation is the natural mode of growth of up to 80% of microorganisms living on this planet. Biofilms refractory towards antimicrobial agents and the actions of the immune system due to their tolerance against multiple environmental stresses. But how did biofilm formation arise? Here, I argue that the biofilm lifestyle has its foundation already in the fundamental, surface-triggered chemical reactions and energy preserving mechanisms that enabled the development of life on earth. Subsequently, prototypical biofilm formation has evolved and diversified concomitantly in composition, cell morphology and regulation with the expansion of prokaryotic organisms and their radiation by occupation of diverse ecological niches. This ancient origin of biofilm formation thus mirrors the harnessing environmental conditions that have been the rule rather than the exception in microbial life. The subsequent emergence of the association of microbes, including recent human pathogens, with higher organisms can be considered as the entry into a nutritional and largely stress-protecting heaven. Nevertheless, basic mechanisms of biofilm formation have surprisingly been conserved and refunctionalized to promote sustained survival in new environments.
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Affiliation(s)
- Ute Römling
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
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25
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Fessia A, Sartori M, García D, Fernández L, Ponzio R, Barros G, Nesci A. In vitro studies of biofilm-forming Bacillus strains, biocontrol agents isolated from the maize phyllosphere. Biofilm 2022; 4:100097. [PMID: 36504526 PMCID: PMC9731887 DOI: 10.1016/j.bioflm.2022.100097] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 11/08/2022] [Accepted: 11/18/2022] [Indexed: 12/12/2022] Open
Abstract
We aimed to assess how biofilm formation by three Bacillus isolates was affected by changes in temperature, water potential, growth media, time, and the combinations between these factors. The strains had been selected as potential biological control agents (BCAs) in earlier studies, and they were identified as B. subtilis and B. velezensis spp. through 16 rRNA sequencing and MALDI-TOF MS. Maize leaves (ML) were used as one of the growth media, since they made it possible to simulate the nutrient content in the maize phyllosphere, from which the bacteria were originally isolated. The strains were able to form biofilm both in ML and biofilm-inducing MSgg after 24, 48, and 72 h. Biofilm development in the form of pellicles and architecturally complex colonies varied morphologically from one strain to another and depended on the conditions mentioned above. In all cases, colonies and pellicles were less complex when both temperature and water potential were lower. Scanning electron microscopy (SEM) revealed that changing levels of complexity in pellicles were correlated with those in colonies. Statistical analyses found that the quantification of biofilm produced by the isolates was influenced by all the conditions tested. In terms of motility (which may contribute to biofilm formation), swimming and swarming were possible for all strains in 0.3 and 0.7% agar, respectively. A more in-depth understanding of how abiotic factors influence biofilm formation can contribute to a more effective use of these biocontrol strains against pathogens in the maize phyllosphere.
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Affiliation(s)
- Aluminé Fessia
- Laboratorio de Ecología Microbiana, Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina,Corresponding author. Laboratorio de Ecología Microbiana, Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina.
| | - Melina Sartori
- Laboratorio de Ecología Microbiana, Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Daiana García
- Laboratorio de Ecología Microbiana, Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Luciana Fernández
- Departamento de Física, Departamento de Química, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, CONICET, X5804BYA, Río Cuarto, Argentina,Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados (IITEMA), Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Rodrigo Ponzio
- Departamento de Física, Departamento de Química, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, CONICET, X5804BYA, Río Cuarto, Argentina,Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados (IITEMA), Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Germán Barros
- Laboratorio de Ecología Microbiana, Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Andrea Nesci
- Laboratorio de Ecología Microbiana, Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
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26
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Gildebrant AV, Sazykin IS, Sazykina MA. Formation of Biofilms by Natural Microbial Strains in the Presence of Naphtalene and Anthracene. APPL BIOCHEM MICRO+ 2022. [DOI: 10.1134/s0003683822090137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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27
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Wang X, Blumenfeld R, Feng XQ, Weitz DA. 'Phase transitions' in bacteria - From structural transitions in free living bacteria to phenotypic transitions in bacteria within biofilms. Phys Life Rev 2022; 43:98-138. [PMID: 36252408 DOI: 10.1016/j.plrev.2022.09.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 09/30/2022] [Indexed: 12/05/2022]
Abstract
Phase transitions are common in inanimate systems and have been studied extensively in natural sciences. Less explored are the rich transitions that take place at the micro- and nano-scales in biological systems. In conventional phase transitions, large-scale properties of the media change discontinuously in response to continuous changes in external conditions. Such changes play a significant role in the dynamic behaviours of organisms. In this review, we focus on some transitions in both free-living and biofilms of bacteria. Particular attention is paid to the transitions in the flagellar motors and filaments of free-living bacteria, in cellular gene expression during the biofilm growth, in the biofilm morphology transitions during biofilm expansion, and in the cell motion pattern transitions during the biofilm formation. We analyse the dynamic characteristics and biophysical mechanisms of these phase transition phenomena and point out the parallels between these transitions and conventional phase transitions. We also discuss the applications of some theoretical and numerical methods, established for conventional phase transitions in inanimate systems, in bacterial biofilms.
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Affiliation(s)
- Xiaoling Wang
- School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083, China; John A. Paulson School of Engineering and Applied Sciences, Harvard University, 9 Oxford St, Cambridge, MA, 02138, USA.
| | - Raphael Blumenfeld
- Gonville & Caius College, University of Cambridge, Trinity St., Cambridge CB2 1TA, UK
| | - Xi-Qiao Feng
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - David A Weitz
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, 9 Oxford St, Cambridge, MA, 02138, USA; Department of Physics, Harvard University, 9 Oxford St, Cambridge, MA, 02138, USA
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28
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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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29
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Park H, Schwartzman AF, Tang TC, Wang L, Lu TK. Ultra-lightweight living structural material for enhanced stiffness and environmental sensing. Mater Today Bio 2022; 18:100504. [PMID: 36504543 PMCID: PMC9729073 DOI: 10.1016/j.mtbio.2022.100504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/20/2022] [Accepted: 11/22/2022] [Indexed: 11/27/2022]
Abstract
Natural materials such as bone, wood, and bamboo can inspire the fabrication of stiff, lightweight structural materials. Biofilms are one of the most dominant forms of life in nature. However, little is known about their physical properties as a structural material. Here we report an Escherichia coli biofilm having a Young's modulus close to 10 GPa with ultra-low density, indicating a high-performance structural material. The mechanical and structural characterization of the biofilm and its components illuminates its adaptable bottom-up design, consisting of lightweight microscale cells covered by a dense network of amyloid nanofibrils on the surface. We engineered E. coli such that 1) carbon nanotubes assembled on the biofilm, enhancing its stiffness to over 30 GPa, or that 2) the biofilm sensitively detected heavy metal as an example of an environmental toxin. These demonstrations offer new opportunities for developing responsive living structural materials to serve many real-world applications.
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Affiliation(s)
- Heechul Park
- Synthetic Biology Group, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA,Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA,Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Alan F. Schwartzman
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Tzu-Chieh Tang
- Synthetic Biology Group, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA,Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA,Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Lei Wang
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Timothy K. Lu
- Synthetic Biology Group, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA,Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA,Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA,Corresponding author. Synthetic Biology Group, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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30
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Arjes HA, Gui H, Porter R, Atolia E, Peters JM, Gross C, Kearns DB, Huang KC. Fatty Acid Synthesis Knockdown Promotes Biofilm Wrinkling and Inhibits Sporulation in Bacillus subtilis. mBio 2022; 13:e0138822. [PMID: 36069446 PMCID: PMC9600695 DOI: 10.1128/mbio.01388-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 08/05/2022] [Indexed: 02/05/2023] Open
Abstract
Many bacterial species typically live in complex three-dimensional biofilms, yet much remains unknown about differences in essential processes between nonbiofilm and biofilm lifestyles. Here, we created a CRISPR interference (CRISPRi) library of knockdown strains covering all known essential genes in the biofilm-forming Bacillus subtilis strain NCIB 3610 and investigated growth, biofilm colony wrinkling, and sporulation phenotypes of the knockdown library. First, we showed that gene essentiality is largely conserved between liquid and surface growth and between two media. Second, we quantified biofilm colony wrinkling using a custom image analysis algorithm and found that fatty acid synthesis and DNA gyrase knockdown strains exhibited increased wrinkling independent of biofilm matrix gene expression. Third, we designed a high-throughput screen to quantify sporulation efficiency after essential gene knockdown; we found that partial knockdowns of essential genes remained competent for sporulation in a sporulation-inducing medium, but knockdown of essential genes involved in fatty acid synthesis exhibited reduced sporulation efficiency in LB, a medium with generally lower levels of sporulation. We conclude that a subset of essential genes are particularly important for biofilm structure and sporulation/germination and suggest a previously unappreciated and multifaceted role for fatty acid synthesis in bacterial lifestyles and developmental processes. IMPORTANCE For many bacteria, life typically involves growth in dense, three-dimensional communities called biofilms that contain cells with differentiated roles held together by extracellular matrix. To examine how essential gene function varies between vegetative growth and the developmental states of biofilm formation and sporulation, we created and screened a comprehensive library of strains using CRISPRi to knockdown expression of each essential gene in the biofilm-capable Bacillus subtilis strain 3610. High-throughput assays and computational algorithms identified a subset of essential genes involved in biofilm wrinkling and sporulation and indicated that fatty acid synthesis plays important and multifaceted roles in bacterial development.
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Affiliation(s)
- Heidi A. Arjes
- Department of Bioengineering, Stanford University School of Medicine, Stanford, California, USA
| | - Haiwen Gui
- Department of Bioengineering, Stanford University School of Medicine, Stanford, California, USA
| | - Rachel Porter
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California, USA
| | - Esha Atolia
- Department of Bioengineering, Stanford University School of Medicine, Stanford, California, USA
| | - Jason M. Peters
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin—Madison, Madison, Wisconsin, USA
- Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin—Madison, Madison, Wisconsin, USA
- Department of Bacteriology, University of Wisconsin—Madison, Madison, Wisconsin, USA
- Department of Medical Microbiology and Immunology, University of Wisconsin—Madison, Madison, Wisconsin, USA
| | - Carol Gross
- Department of Microbiology and Immunology, University of California San Francisco, San Francisco, California, USA
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, California, USA
| | - Daniel B. Kearns
- Department of Biology, Indiana University, Bloomington, Indiana, USA
| | - Kerwyn Casey Huang
- Department of Bioengineering, Stanford University School of Medicine, Stanford, California, USA
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California, USA
- Chan Zuckerberg Biohub, San Francisco, California, USA
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31
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Zhao J, Ni G, Piculell M, Li J, Hu Z, Wang Z, Guo J, Yuan Z, Zheng M, Hu S. Characterizing and comparing microbial community and biofilm structure in three nitrifying moving bed biofilm reactors. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 320:115883. [PMID: 35930881 DOI: 10.1016/j.jenvman.2022.115883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 06/29/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
This study investigated biofilm establishment, biofilm structure, and microbial community composition of biofilms in three laboratory-scale moving bed biofilm reactors. These reactors were filled with three types of plastic carriers with varied depths of living space for microbial growth. The reactors were operated under the same influent and operational conditions. Along with the operation, the results showed that carriers with grids of 50 μm in height delayed the biofilm development and formed the thinnest biofilm and a carpet-like structure with the lowest α-diversity. In comparison, another two carriers with grids of 200 and 400 μm in height formed thick biofilms and large colonies with more voids and channels. Quantified properties of biofilm thickness, biomass, heterogeneity, portion of the biofilm exposed to the nutrient, and maximum diffusion distance were examined, and the results demonstrated that they almost (except for heterogeneity) strongly correlated to the α-diversity of microbial community. These illustrate that depth of living space, as an important parameter for carrier, could drive the formation of biofilm structure and community composition. It improves understanding of influencing factors on biofilm establishment, structure and its microbial community, and would be helpful for the design of biofilm processes.
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Affiliation(s)
- Jing Zhao
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Gaofeng Ni
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Maria Piculell
- Veolia Water Technologies AB - AnoxKaldnes, Klosterängsvägen 11A, SE-226 47, Lund, Sweden
| | - Jie Li
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Zhetai Hu
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Zhiyao Wang
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Jianhua Guo
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Zhiguo Yuan
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Min Zheng
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia.
| | - Shihu Hu
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia.
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32
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Mashruwala AA, Qin B, Bassler BL. Quorum-sensing- and type VI secretion-mediated spatiotemporal cell death drives genetic diversity in Vibrio cholerae. Cell 2022; 185:3966-3979.e13. [PMID: 36167071 PMCID: PMC9623500 DOI: 10.1016/j.cell.2022.09.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 07/03/2022] [Accepted: 08/31/2022] [Indexed: 01/26/2023]
Abstract
Bacterial colonies composed of genetically identical individuals can diversify to yield variant cells with distinct genotypes. Variant outgrowth manifests as sectors. Here, we show that Type VI secretion system (T6SS)-driven cell death in Vibrio cholerae colonies imposes a selective pressure for the emergence of variant strains that can evade T6SS-mediated killing. T6SS-mediated cell death occurs in two distinct spatiotemporal phases, and each phase is driven by a particular T6SS toxin. The first phase is regulated by quorum sensing and drives sectoring. The second phase does not require the T6SS-injection machinery. Variant V. cholerae strains isolated from colony sectors encode mutated quorum-sensing components that confer growth advantages by suppressing T6SS-killing activity while simultaneously boosting T6SS-killing defenses. Our findings show that the T6SS can eliminate sibling cells, suggesting a role in intra-specific antagonism. We propose that quorum-sensing-controlled T6SS-driven killing promotes V. cholerae genetic diversity, including in natural habitats and during disease.
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Affiliation(s)
- Ameya A. Mashruwala
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA,The Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Boyang Qin
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA,Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Bonnie L. Bassler
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA,The Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA,Lead Contact,Correspondence:
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33
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Zhang Y, Cai Y, Zeng L, Liu P, Ma LZ, Liu J. A Microfluidic Approach for Quantitative Study of Spatial Heterogeneity in Bacterial Biofilms. SMALL SCIENCE 2022. [DOI: 10.1002/smsc.202200047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Yuzhen Zhang
- Center for Infectious Disease Research School of Medicine Tsinghua University Beijing 100084 China
- Tsinghua-Peking Center for Life Sciences Beijing 100084 China
| | - Yumin Cai
- Center for Infectious Disease Research School of Medicine Tsinghua University Beijing 100084 China
| | - Lingbin Zeng
- Center for Infectious Disease Research School of Medicine Tsinghua University Beijing 100084 China
| | - Peng Liu
- Department of Biomedical Engineering School of Medicine Tsinghua University Beijing 100084 China
| | - Luyan Z. Ma
- State Key Laboratory of Microbial Resources Institute of Microbiology Chinese Academy of Sciences Beijing 100101 China
| | - Jintao Liu
- Center for Infectious Disease Research School of Medicine Tsinghua University Beijing 100084 China
- Tsinghua-Peking Center for Life Sciences Beijing 100084 China
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34
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Effect of a Stannous Fluoride Dentifrice on Biofilm Composition, Gene Expression and Biomechanical Properties. Microorganisms 2022; 10:microorganisms10091691. [PMID: 36144293 PMCID: PMC9506307 DOI: 10.3390/microorganisms10091691] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 08/17/2022] [Accepted: 08/18/2022] [Indexed: 11/16/2022] Open
Abstract
An in situ study was conducted to examine the mode of action of a 0.454% stannous fluoride (SnF2)-containing dentifrice in controlling the composition and properties of oral biofilm. Thirteen generally healthy individuals participated in the study. Each participant wore an intra-oral appliance over a 48-h period to measure differences in the resulting biofilm’s architecture, mechanical properties, and bacterial composition after using two different toothpaste products. In addition, metatranscriptomics analysis of supragingival plaque was conducted to identify the gene pathways influenced. The thickness and volume of the microcolonies formed when brushing with the SnF2 dentifrice were dramatically reduced compared to the control 0.76% sodium monofluorophosphate (MFP)-containing toothpaste. Similarly, the biophysical and nanomechanical properties measured by atomic force microscopy (AFM) demonstrated a significant reduction in biofilm adhesive properties. Metatranscriptomic analysis identified pathways associated with biofilm formation, cell adhesion, quorum sensing, and N-glycosylation that are significantly downregulated with SnF2. This study provides a clinically relevant snapshot of how the use of a stabilized, SnF2 toothpaste formulation can change the spatial organization, nanomechanical, and gene expression properties of bacterial communities.
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35
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VxrB Influences Antagonism within Biofilms by Controlling Competition through Extracellular Matrix Production and Type 6 Secretion. mBio 2022; 13:e0188522. [PMID: 35880882 PMCID: PMC9426512 DOI: 10.1128/mbio.01885-22] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The human pathogen Vibrio cholerae grows as biofilms, communities of cells encased in an extracellular matrix. When growing in biofilms, cells compete for resources and space. One common competitive mechanism among Gram-negative bacteria is the type six secretion system (T6SS), which can deliver toxic effector proteins into a diverse group of target cells, including other bacteria, phagocytic amoebas, and human macrophages. The response regulator VxrB positively regulates both biofilm matrix and T6SS gene expression. Here, we directly observe T6SS activity within biofilms, which results in improved competition with strains lacking the T6SS. VxrB significantly contributes to both attack and defense via T6SS, while also influencing competition via regulation of biofilm matrix production. We further determined that both Vibrio polysaccharide (VPS) and the biofilm matrix protein RbmA can protect cells from T6SS attack within mature biofilms. By varying the spatial mixing of predator and prey cells in biofilms, we show that a high degree of mixing favors T6SS predator strains and that the presence of extracellular DNA in V. cholerae biofilms is a signature of T6SS killing. VxrB therefore regulates both T6SS attack and matrix-based T6SS defense, to control antagonistic interactions and competition outcomes during mixed-strain biofilm formation.
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36
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Liu X, Inda ME, Lai Y, Lu TK, Zhao X. Engineered Living Hydrogels. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2201326. [PMID: 35243704 PMCID: PMC9250645 DOI: 10.1002/adma.202201326] [Citation(s) in RCA: 62] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 03/01/2022] [Indexed: 05/31/2023]
Abstract
Living biological systems, ranging from single cells to whole organisms, can sense, process information, and actuate in response to changing environmental conditions. Inspired by living biological systems, engineered living cells and nonliving matrices are brought together, which gives rise to the technology of engineered living materials. By designing the functionalities of living cells and the structures of nonliving matrices, engineered living materials can be created to detect variability in the surrounding environment and to adjust their functions accordingly, thereby enabling applications in health monitoring, disease treatment, and environmental remediation. Hydrogels, a class of soft, wet, and biocompatible materials, have been widely used as matrices for engineered living cells, leading to the nascent field of engineered living hydrogels. Here, the interactions between hydrogel matrices and engineered living cells are described, focusing on how hydrogels influence cell behaviors and how cells affect hydrogel properties. The interactions between engineered living hydrogels and their environments, and how these interactions enable versatile applications, are also discussed. Finally, current challenges facing the field of engineered living hydrogels for their applications in clinical and environmental settings are highlighted.
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Affiliation(s)
- Xinyue Liu
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Maria Eugenia Inda
- Synthetic Biology Group, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Yong Lai
- Synthetic Biology Group, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Timothy K Lu
- Synthetic Biology Group, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Xuanhe Zhao
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
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37
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Geisel S, Secchi E, Vermant J. The role of surface adhesion on the macroscopic wrinkling of biofilms. eLife 2022; 11:e76027. [PMID: 35723588 PMCID: PMC9208754 DOI: 10.7554/elife.76027] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 06/01/2022] [Indexed: 12/14/2022] Open
Abstract
Biofilms, bacterial communities of cells encased by a self-produced matrix, exhibit a variety of three-dimensional structures. Specifically, channel networks formed within the bulk of the biofilm have been identified to play an important role in the colonies' viability by promoting the transport of nutrients and chemicals. Here, we study channel formation and focus on the role of the adhesion of the biofilm matrix to the substrate in Pseudomonas aeruginosa biofilms grown under constant flow in microfluidic channels. We perform phase contrast and confocal laser scanning microscopy to examine the development of the biofilm structure as a function of the substrates' surface energy. The formation of the wrinkles and folds is triggered by a mechanical buckling instability, controlled by biofilm growth rate and the film's adhesion to the substrate. The three-dimensional folding gives rise to hollow channels that rapidly increase the effective volume occupied by the biofilm and facilitate bacterial movement inside them. The experiments and analysis on mechanical instabilities for the relevant case of a bacterial biofilm grown during flow enable us to predict and control the biofilm morphology.
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Affiliation(s)
- Steffen Geisel
- Laboratory for Soft Materials, Department of Materials, ETH ZurichZurichSwitzerland
| | - Eleonora Secchi
- Department of Civil, Environmental and Geomatic Engineering, ETH ZurichZurichSwitzerland
| | - Jan Vermant
- Laboratory for Soft Materials, Department of Materials, ETH ZurichZurichSwitzerland
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38
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Keren-Paz A, Maan H, Karunker I, Olender T, Kapishnikov S, Dersch S, Kartvelishvily E, Wolf SG, Gal A, Graumann PL, Kolodkin-Gal I. The roles of intracellular and extracellular calcium in Bacillus subtilis biofilms. iScience 2022; 25:104308. [PMID: 35663026 PMCID: PMC9160756 DOI: 10.1016/j.isci.2022.104308] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 03/26/2022] [Accepted: 04/22/2022] [Indexed: 11/06/2022] Open
Abstract
In nature, bacteria reside in biofilms– multicellular differentiated communities held together by an extracellular matrix. This work identified a novel subpopulation—mineral-forming cells—that is essential for biofilm formation in Bacillus subtilis biofilms. This subpopulation contains an intracellular calcium-accumulating niche, in which the formation of a calcium carbonate mineral is initiated. As the biofilm colony develops, this mineral grows in a controlled manner, forming a functional macrostructure that serves the entire community. Consistently, biofilm development is prevented by the inhibition of calcium uptake. Our results provide a clear demonstration of the orchestrated production of calcite exoskeleton, critical to morphogenesis in simple prokaryotes. The orchestrated formation of calcite scaffolds supports the morphogenesis of microbial biofilms A novel subpopulation—mineral-forming cells—is essential for biofilm formation This subpopulation contains an intracellular calcium-accumulating niche, supporting the formation of calcium carbonate Intracellular calcium homeostasis and calcium export are associated with a functional biofilm macrostructure
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Affiliation(s)
- Alona Keren-Paz
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Harsh Maan
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Iris Karunker
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Tsviya Olender
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Sergey Kapishnikov
- Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel
| | - Simon Dersch
- Centre for Synthetic Microbiology (SYNMIKRO), Fachbereich Chemie, Philipps-Universität Marburg, Marburg, Germany
| | | | - Sharon G Wolf
- Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel
| | - Assaf Gal
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Peter L Graumann
- Centre for Synthetic Microbiology (SYNMIKRO), Fachbereich Chemie, Philipps-Universität Marburg, Marburg, Germany
| | - Ilana Kolodkin-Gal
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel.,Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
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39
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Surapaneni VA, Schindler M, Ziege R, de Faria LC, Wölfer J, Bidan CM, Mollen FH, Amini S, Hanna S, Dean MN. Groovy and Gnarly: Surface Wrinkles as a Multifunctional Motif for Terrestrial and Marine Environments. Integr Comp Biol 2022; 62:icac079. [PMID: 35675323 PMCID: PMC9703940 DOI: 10.1093/icb/icac079] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/23/2022] [Accepted: 05/24/2022] [Indexed: 12/12/2022] Open
Abstract
From large ventral pleats of humpback whales to nanoscale ridges on flower petals, wrinkled structures are omnipresent, multifunctional, and found at hugely diverse scales. Depending on the particulars of the biological system-its environment, morphology, and mechanical properties-wrinkles may control adhesion, friction, wetting, or drag; promote interfacial exchange; act as flow channels; or contribute to stretching, mechanical integrity, or structural color. Undulations on natural surfaces primarily arise from stress-induced instabilities of surface layers (e.g., buckling) during growth or aging. Variation in the material properties of surface layers and in the magnitude and orientation of intrinsic stresses during growth lead to a variety of wrinkling morphologies and patterns which, in turn, reflect the wide range of biophysical challenges wrinkled surfaces can solve. Therefore, investigating how surface wrinkles vary and are implemented across biological systems is key to understanding their structure-function relationships. In this work, we synthesize the literature in a metadata analysis of surface wrinkling in various terrestrial and marine organisms to review important morphological parameters and classify functional aspects of surface wrinkles in relation to the size and ecology of organisms. Building on our previous and current experimental studies, we explore case studies on nano/micro-scale wrinkles in biofilms, plant surfaces, and basking shark filter structures to compare developmental and structure-vs-function aspects of wrinkles with vastly different size scales and environmental demands. In doing this and by contrasting wrinkle development in soft and hard biological systems, we provide a template of structure-function relationships of biological surface wrinkles and an outlook for functionalized wrinkled biomimetic surfaces.
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Affiliation(s)
- Venkata A Surapaneni
- City University of Hong Kong, 31 To Yuen Street, Kowloon, Hong Kong
- Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, Potsdam, Brandenburg 14476, Germany
| | - Mike Schindler
- City University of Hong Kong, 31 To Yuen Street, Kowloon, Hong Kong
| | - Ricardo Ziege
- Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, Potsdam, Brandenburg 14476, Germany
| | | | - Jan Wölfer
- Humboldt University of Berlin, Unter den Linden 6, Berlin 10099, Germany
| | - Cécile M Bidan
- Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, Potsdam, Brandenburg 14476, Germany
| | - Frederik H Mollen
- Elasmobranch Research Belgium, Rehaegenstraat 4, 2820 Bonheiden, Belgium
| | - Shahrouz Amini
- Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, Potsdam, Brandenburg 14476, Germany
| | - Sean Hanna
- University College London, 14 Upper Woburn Place, London WC1H 0NN, UK
| | - Mason N Dean
- City University of Hong Kong, 31 To Yuen Street, Kowloon, Hong Kong
- Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, Potsdam, Brandenburg 14476, Germany
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40
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Eigentler L, Kalamara M, Ball G, MacPhee CE, Stanley-Wall NR, Davidson FA. Founder cell configuration drives competitive outcome within colony biofilms. THE ISME JOURNAL 2022; 16:1512-1522. [PMID: 35121821 PMCID: PMC9122948 DOI: 10.1038/s41396-022-01198-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 01/03/2022] [Accepted: 01/17/2022] [Indexed: 11/19/2022]
Abstract
Bacteria can form dense communities called biofilms, where cells are embedded in a self-produced extracellular matrix. Exploiting competitive interactions between strains within the biofilm context can have potential applications in biological, medical, and industrial systems. By combining mathematical modelling with experimental assays, we reveal that spatial structure and competitive dynamics within biofilms are significantly affected by the location and density of the founder cells used to inoculate the biofilm. Using a species-independent theoretical framework describing colony biofilm formation, we show that the observed spatial structure and relative strain biomass in a mature biofilm comprising two isogenic strains can be mapped directly to the geographical distributions of founder cells. Moreover, we define a predictor of competitive outcome that accurately forecasts relative abundance of strains based solely on the founder cells' potential for radial expansion. Consequently, we reveal that variability of competitive outcome in biofilms inoculated at low founder density is a natural consequence of the random positioning of founding cells in the inoculum. Extension of our study to non-isogenic strains that interact through local antagonisms, shows that even for strains with different competition strengths, a race for space remains the dominant mode of competition in low founder density biofilms. Our results, verified by experimental assays using Bacillus subtilis, highlight the importance of spatial dynamics on competitive interactions within biofilms and hence to related applications.
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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
| | - Margarita Kalamara
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Graeme Ball
- Dundee Imaging Facility, School of Life Sciences, University of Dundee, Dundee, DD1 5HN, UK
| | - Cait E MacPhee
- School of Physics and Astronomy, The University of Edinburgh, Edinburgh, EH9 3FD, UK
| | - Nicola R Stanley-Wall
- Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK.
| | - Fordyce A Davidson
- Mathematics, School of Science and Engineering, University of Dundee, Dundee, DD1 4HN, UK.
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41
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Day TC, Márquez-Zacarías P, Bravo P, Pokhrel AR, MacGillivray KA, Ratcliff WC, Yunker PJ. Varied solutions to multicellularity: The biophysical and evolutionary consequences of diverse intercellular bonds. BIOPHYSICS REVIEWS 2022; 3:021305. [PMID: 35673523 PMCID: PMC9164275 DOI: 10.1063/5.0080845] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 04/29/2022] [Indexed: 11/16/2022]
Abstract
The diversity of multicellular organisms is, in large part, due to the fact that multicellularity has independently evolved many times. Nonetheless, multicellular organisms all share a universal biophysical trait: cells are attached to each other. All mechanisms of cellular attachment belong to one of two broad classes; intercellular bonds are either reformable or they are not. Both classes of multicellular assembly are common in nature, having independently evolved dozens of times. In this review, we detail these varied mechanisms as they exist in multicellular organisms. We also discuss the evolutionary implications of different intercellular attachment mechanisms on nascent multicellular organisms. The type of intercellular bond present during early steps in the transition to multicellularity constrains future evolutionary and biophysical dynamics for the lineage, affecting the origin of multicellular life cycles, cell-cell communication, cellular differentiation, and multicellular morphogenesis. The types of intercellular bonds used by multicellular organisms may thus result in some of the most impactful historical constraints on the evolution of multicellularity.
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Affiliation(s)
- Thomas C. Day
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | | | | | - Aawaz R. Pokhrel
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | | | - William C. Ratcliff
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Peter J. Yunker
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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42
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Cervantes-Huamán B, Ripolles-Avila C, Mazaheri T, Rodríguez-Jerez J. Pathogenic mono-species biofilm formation on stainless steel surfaces: Quantitative, qualitative, and compositional study. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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43
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Alric B, Formosa-Dague C, Dague E, Holt LJ, Delarue M. Macromolecular crowding limits growth under pressure. NATURE PHYSICS 2022; 18:411-416. [PMID: 37152719 PMCID: PMC10162713 DOI: 10.1038/s41567-022-01506-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Cells that grow in confined spaces eventually build up mechanical compressive stress. This growth-induced pressure (GIP) decreases cell growth. GIP is important in a multitude of contexts from cancer, to microbial infections, to biofouling, yet our understanding of its origin and molecular consequences remains limited. Here, we combine microfluidic confinement of the yeast Saccharomyces cerevisiae, with rheological measurements using genetically encoded multimeric nanoparticles (GEMs) to reveal that growth-induced pressure is accompanied with an increase in a key cellular physical property: macromolecular crowding. We develop a fully calibrated model that predicts how increased macromolecular crowding hinders protein expression and thus diminishes cell growth. This model is sufficient to explain the coupling of growth rate to pressure without the need for specific molecular sensors or signaling cascades. As molecular crowding is similar across all domains of life, this could be a deeply conserved mechanism of biomechanical feedback that allows environmental sensing originating from the fundamental physical properties of cells.
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Affiliation(s)
- Baptiste Alric
- MILE team, CNRS, UPR8001, LAAS-CNRS, 7 Avenue du Colonel Roche, F-31400 Toulouse, France
| | | | - Etienne Dague
- ELIA team, CNRS, UPR8001, LAAS-CNRS, 7 Avenue du Colonel Roche, F-31400 Toulouse, France
| | - Liam J. Holt
- New York University Grossman School of Medicine, Institute for Systems Genetics, 435 E 30th Street, New York, NY, United States
- to whom correspondence should be addressed: ;
| | - Morgan Delarue
- MILE team, CNRS, UPR8001, LAAS-CNRS, 7 Avenue du Colonel Roche, F-31400 Toulouse, France
- to whom correspondence should be addressed: ;
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44
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Artificial Human Sweat as a Novel Growth Condition for Clinically Relevant Pathogens on Hospital Surfaces. Microbiol Spectr 2022; 10:e0213721. [PMID: 35357242 PMCID: PMC9045197 DOI: 10.1128/spectrum.02137-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The emergence of biofilms on dry hospital surfaces has led to the development of numerous models designed to challenge the efficacious properties of common antimicrobial agents used in cleaning. This is in spite of limited research defining how dry surfaces are able to facilitate biofilm growth and formation in such desiccating and nutrient-deprived environments. While it is well established that the phenotypical response of biofilms is dependent on the conditions in which they are formed, most models incorporate a nutrient-enriched, hydrated environment dissimilar to the clinical setting. In this study, we piloted a novel culture medium, artificial human sweat (AHS), which is perceived to be more indicative of the nutrient sources available on hospital surfaces, particularly those in close proximity to patients. AHS was capable of sustaining the proliferation of four clinically relevant multidrug-resistant pathogens (Acinetobacter baumannii, Staphylococcus aureus, Enterococcus faecalis, and Pseudomonas aeruginosa) and achieved biofilm formation at concentration levels equivalent to those found in situ (average, 6.00 log10 CFU/cm2) with similar visual characteristics upon microscopy. The AHS model presented here could be used for downstream applications, including efficacy testing of hospital cleaning products, due to its resemblance to clinical biofilms on dry surfaces. This may contribute to a better understanding of the true impact these products have on surface hygiene. IMPORTANCE Precise modeling of dry surface biofilms in hospitals is critical for understanding their role in hospital-acquired infection transmission and surface contamination. Using a representative culture condition which includes a nutrient source is key to developing a phenotypically accurate biofilm community. This will enable accurate laboratory testing of cleaning products and their efficacy against dry surface biofilms.
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45
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Ivo Ganchev. Role of Multispecies Biofilms with a Dominance of Bacillus subtilis in the Rhizosphere. BIOL BULL+ 2022. [DOI: 10.1134/s1062359021150061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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46
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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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47
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Abstract
Bacillus subtilis is a soil bacterium that can form biofilms, which are communities of cells encased by an extracellular matrix. In these complex communities, cells perform numerous metabolic processes and undergo differentiation into functionally distinct phenotypes as a survival strategy. Because biofilms are often studied in bulk, it remains unclear how metabolite production spatially correlates with B. subtilis phenotypes within biofilm structures. In many cases, we still do not know where these biological processes are occurring in the biofilm. Here, we developed a method to analyze the localization of molecules within sagittal thin sections of B. subtilis biofilms using high-resolution mass spectrometry imaging. We correlated the organization of specific molecules to the localization of well-studied B. subtilis phenotypic reporters determined by confocal laser scanning fluorescence microscopy within analogous biofilm thin sections. The correlations between these two data sets suggest the role of surfactin as a signal for extracellular matrix gene expression in the biofilm periphery and the role of bacillibactin as an iron-scavenging molecule. Taken together, this method will help us generate hypotheses to discover relationships between metabolites and phenotypic cell states in B. subtilis and other biofilm-forming bacteria. IMPORTANCE Bacterial biofilms are complex and heterogeneous structures. Cells within biofilms carry out numerous metabolic processes in a nuanced and organized manner, details of which are still being discovered. Here, we used multimodal imaging to analyze B. subtilis biofilm processes at the metabolic and gene expression levels in biofilm sagittal thin sections. Often, imaging techniques analyze only the top of the surface of the biofilm and miss the multifaceted interactions that occur deep within the biofilm. Our analysis of the sagittal planes of B. subtilis biofilms revealed the distributions of metabolic processes throughout the depths of these structures and allowed us to draw correlations between metabolites and phenotypically important subpopulations of B. subtilis cells. This technique provides a platform to generate hypotheses about the role of specific molecules and their relationships to B. subtilis subpopulations of cells.
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48
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Nijjer J, Li C, Zhang Q, Lu H, Zhang S, Yan J. Mechanical forces drive a reorientation cascade leading to biofilm self-patterning. Nat Commun 2021; 12:6632. [PMID: 34789754 PMCID: PMC8599862 DOI: 10.1038/s41467-021-26869-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 10/26/2021] [Indexed: 01/12/2023] Open
Abstract
In growing active matter systems, a large collection of engineered or living autonomous units metabolize free energy and create order at different length scales as they proliferate and migrate collectively. One such example is bacterial biofilms, surface-attached aggregates of bacterial cells embedded in an extracellular matrix that can exhibit community-scale orientational order. However, how bacterial growth coordinates with cell-surface interactions to create distinctive, long-range order during biofilm development remains elusive. Here we report a collective cell reorientation cascade in growing Vibrio cholerae biofilms that leads to a differentially ordered, spatiotemporally coupled core-rim structure reminiscent of a blooming aster. Cell verticalization in the core leads to a pattern of differential growth that drives radial alignment of the cells in the rim, while the growing rim generates compressive stresses that expand the verticalized core. Such self-patterning disappears in nonadherent mutants but can be restored through opto-manipulation of growth. Agent-based simulations and two-phase active nematic modeling jointly reveal the strong interdependence of the driving forces underlying the differential ordering. Our findings offer insight into the developmental processes that shape bacterial communities and provide ways to engineer phenotypes and functions in living active matter.
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Affiliation(s)
- Japinder Nijjer
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Changhao Li
- Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA, USA
| | - Qiuting Zhang
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Haoran Lu
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Sulin Zhang
- Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA, USA.
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, USA.
| | - Jing Yan
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA.
- Quantitative Biology Institute, Yale University, New Haven, CT, USA.
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49
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Pattem J, Davrandi M, Aguayo S, Slak B, Maev R, Allan E, Spratt D, Bozec L. Dependency of hydration and growth conditions on the mechanical properties of oral biofilms. Sci Rep 2021; 11:16234. [PMID: 34376751 PMCID: PMC8355335 DOI: 10.1038/s41598-021-95701-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 07/21/2021] [Indexed: 11/21/2022] Open
Abstract
Within the oral cavity, dental biofilms experience dynamic environments, in part due to changes in dietary content, frequency of intake and health conditions. This can impact bacterial diversity and morpho-mechanical properties. While phenotypic properties of oral biofilms are closely related to their composition, these can readily change according to dynamic variations in the growth environment and nutrient availability. Understanding the interlink between phenotypic properties, variable growth conditions, and community characterization is an essential requirement to develop structure–property relationships in oral-biofilms. In this study, the impact of two distinct growth media types with increasing richness on the properties of oral biofilms was assessed through a new combination of in-vitro time-lapse biophysical methods with microbiological assays. Oral biofilms grown in the enriched media composition presented a decrease in their pH, an increase in soluble EPS production, and a severe reduction in bacterial diversity. Additionally, enriched media conditions presented an increase in biofilm volumetric changes (upon hydration) as well as a reduction in elastic modulus upon indentation. With hydration time considered a major factor contributing to changes in biofilm mechanical properties, we have shown that it is less associated than media richness. Future investigations can now use this time-lapse approach, with a clearer focus on the extracellular matrix of oral biofilms dictating their morpho-mechanical properties.
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Affiliation(s)
- J Pattem
- Division of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, University College London, London, UK. .,National Centre for Molecular Hydrodynamics, and Soft Matter Biomaterials and Bio-Interfaces, University of Nottingham, The Limes Building, Sutton Bonington Campus, Sutton Bonington, Leicestershire, LE12 5RD, UK.
| | - M Davrandi
- Division of Microbial Diseases, UCL Eastman Dental Institute, University College London, London, UK
| | - S Aguayo
- School of Dentistry, Faculty of Medicine, Pontificia Universidad Catolica de Chile, Santiago, Chile
| | - B Slak
- Department of Electrical and Computer Engineering, University of Windsor, Windsor, Canada
| | - R Maev
- Department of Electrical and Computer Engineering, University of Windsor, Windsor, Canada
| | - E Allan
- Division of Microbial Diseases, UCL Eastman Dental Institute, University College London, London, UK
| | - D Spratt
- Division of Microbial Diseases, UCL Eastman Dental Institute, University College London, London, UK
| | - L Bozec
- Division of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, University College London, London, UK.,Faculty of Dentistry, University of Toronto, Toronto, Canada
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50
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Causes and consequences of pattern diversification in a spatially self-organizing microbial community. THE ISME JOURNAL 2021; 15:2415-2426. [PMID: 33664433 PMCID: PMC8319339 DOI: 10.1038/s41396-021-00942-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 02/06/2021] [Accepted: 02/15/2021] [Indexed: 01/31/2023]
Abstract
Surface-attached microbial communities constitute a vast amount of life on our planet. They contribute to all major biogeochemical cycles, provide essential services to our society and environment, and have important effects on human health and disease. They typically consist of different interacting genotypes that arrange themselves non-randomly across space (referred to hereafter as spatial self-organization). While spatial self-organization is important for the functioning, ecology, and evolution of these communities, the underlying determinants of spatial self-organization remain unclear. Here, we performed a combination of experiments, statistical modeling, and mathematical simulations with a synthetic cross-feeding microbial community consisting of two isogenic strains. We found that two different patterns of spatial self-organization emerged at the same length and time scales, thus demonstrating pattern diversification. This pattern diversification was not caused by initial environmental heterogeneity or by genetic heterogeneity within populations. Instead, it was caused by nongenetic heterogeneity within populations, and we provide evidence that the source of this nongenetic heterogeneity is local differences in the initial spatial positionings of individuals. We further demonstrate that the different patterns exhibit different community-level properties; namely, they have different expansion speeds. Together, our results demonstrate that pattern diversification can emerge in the absence of initial environmental heterogeneity or genetic heterogeneity within populations and can affect community-level properties, thus providing novel insights into the causes and consequences of microbial spatial self-organization.
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