1
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Blondel M, Machet C, Wildemann B, Abidine Y, Swider P. Mechanobiology of bacterial biofilms: Implications for orthopedic infection. J Orthop Res 2024; 42:1861-1869. [PMID: 38432991 DOI: 10.1002/jor.25822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 02/14/2024] [Accepted: 02/19/2024] [Indexed: 03/05/2024]
Abstract
Postoperative bacterial infections are prevalent complications in both human and veterinary orthopedic surgery, particularly when a biofilm develops. These infections often result in delayed healing, early revision, permanent functional loss, and, in severe cases, amputation. The diagnosis and treatment pose significant challenges, and bacterial biofilm further amplifies the therapeutic difficulty as it confers protection against the host immune system and against antibiotics which are usually administered as a first-line therapeutic option. However, the inappropriate use of antibiotics has led to the emergence of numerous multidrug-resistant organisms, which largely compromise the already imperfect treatment efficiency. In this context, the study of bacterial biofilm formation allows to better target antibiotic use and to evaluate alternative therapeutic strategies. Exploration of the roles played by mechanical factors on biofilm development is of particular interest, especially because cartilage and bone tissues are reactive environments that are subjected to mechanical load. This review delves into the current landscape of biofilm mechanobiology, exploring the role of mechanical factors on biofilm development through a multiscale prism starting from bacterial microscopic scale to reach biofilm mesoscopic size and finally the macroscopic scale of the fracture site or bone-implant interface.
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Affiliation(s)
- Margaux Blondel
- Small Animal Surgery Department, Lyon University, VetAgro Sup, Marcy l'Etoile, France
| | - Camille Machet
- National Veterinary School of Toulouse, Toulouse, France
| | - Britt Wildemann
- Experimental Trauma Surgery, Department of Trauma, Hand and Reconstructive Surgery, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Yara Abidine
- Institut de Mécanique des Fluides (IMFT), CNRS & Toulouse University, Toulouse, France
| | - Pascal Swider
- Institut de Mécanique des Fluides (IMFT), CNRS & Toulouse University, Toulouse, France
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2
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Vázquez R, Gutiérrez D, Dezutter Z, Criel B, de Groote P, Briers Y. You get what you test for: The killing effect of phage lysins is highly dependent on buffer tonicity and ionic strength. Microb Biotechnol 2024; 17:e14513. [PMID: 38962879 PMCID: PMC11222872 DOI: 10.1111/1751-7915.14513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 06/05/2024] [Accepted: 06/09/2024] [Indexed: 07/05/2024] Open
Abstract
The phage lysin field has done nothing but grow in the last decades. As a result, many different research groups around the world are contributing to the field, often with certain methodological differences that pose a challenge to the interpretation and comparison of results. In this work, we present the case study of three Acinetobacter baumannii-targeting phage lysins (wild-type endolysin LysMK34 plus engineered lysins eLysMK34 and 1D10) plus one lysin with broad activity against Gram-positive bacteria (PlySs2) to provide exemplary evidence on the risks of generalization when using one of the most common lysin evaluation assays: the killing assay with resting cells. To that end, we performed killing assays with the aforementioned lysins using hypo-, iso- and hypertonic buffers plus human serum either as the reaction or the dilution medium in a systematic manner. Our findings stress the perils of creating hypotonic conditions or a hypotonic shock during a killing assay, suggesting that hypotonic buffers should be avoided as a test environment or as diluents before plating to avoid overestimation of the killing effect in the assayed conditions. As a conclusion, we suggest that the nature of both the incubation and the dilution buffers should be always clearly identified when reporting killing activity data, and that for experimental consistency the same incubation buffer should be used as a diluent for posterior serial dilution and plating unless explicitly required by the experimental design. In addition, the most appropriate buffer mimicking the final application must be chosen to obtain relevant results.
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Affiliation(s)
- Roberto Vázquez
- Department of BiotechnologyGhent UniversityGhentBelgium
- Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES)MadridSpain
| | | | - Zoë Dezutter
- Department of BiotechnologyGhent UniversityGhentBelgium
| | - Bjorn Criel
- Department of BiotechnologyGhent UniversityGhentBelgium
| | | | - Yves Briers
- Department of BiotechnologyGhent UniversityGhentBelgium
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3
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Dorrazehi GM, Winkle M, Desmet M, Stroobant V, Tanriver G, Degand H, Evrard D, Desguin B, Morsomme P, Biboy J, Gray J, Mitusińska K, Góra A, Vollmer W, Soumillion P. PBP-A, a cyanobacterial DD-peptidase with high specificity for amidated muropeptides, exhibits pH-dependent promiscuous activity harmful to Escherichia coli. Sci Rep 2024; 14:13999. [PMID: 38890528 PMCID: PMC11189452 DOI: 10.1038/s41598-024-64806-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: 02/22/2024] [Accepted: 06/13/2024] [Indexed: 06/20/2024] Open
Abstract
Penicillin binding proteins (PBPs) are involved in biosynthesis, remodeling and recycling of peptidoglycan (PG) in bacteria. PBP-A from Thermosynechococcus elongatus belongs to a cyanobacterial family of enzymes sharing close structural and phylogenetic proximity to class A β-lactamases. With the long-term aim of converting PBP-A into a β-lactamase by directed evolution, we simulated what may happen when an organism like Escherichia coli acquires such a new PBP and observed growth defect associated with the enzyme activity. To further explore the molecular origins of this harmful effect, we decided to characterize deeper the activity of PBP-A both in vitro and in vivo. We found that PBP-A is an enzyme endowed with DD-carboxypeptidase and DD-endopeptidase activities, featuring high specificity towards muropeptides amidated on the D-iso-glutamyl residue. We also show that a low promiscuous activity on non-amidated peptidoglycan deteriorates E. coli's envelope, which is much higher under acidic conditions where substrate discrimination is mitigated. Besides expanding our knowledge of the biochemical activity of PBP-A, this work also highlights that promiscuity may depend on environmental conditions and how it may hinder rather than promote enzyme evolution in nature or in the laboratory.
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Affiliation(s)
- Gol Mohammad Dorrazehi
- Louvain Institute of Biomolecular Science and Technology, UCLouvain, Place Croix du Sud 4-5, 1348, Louvain-la-Neuve, Belgium
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Matthias Winkle
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX, UK
- Benchmark Animal Health Ltd, 1 Pioneer Building, Edinburgh Technopole, Milton Bridge, Penicuik, EH26 0GB, UK
| | - Martin Desmet
- Louvain Institute of Biomolecular Science and Technology, UCLouvain, Place Croix du Sud 4-5, 1348, Louvain-la-Neuve, Belgium
| | - Vincent Stroobant
- Ludwig Institute for Cancer Research, Brussels, Belgium
- de Duve Institute, UCLouvain, Brussels, Belgium
| | - Gamze Tanriver
- Tunneling Group, Biotechnology Centre, Silesian University of Technology, 44-100, Gliwice, Poland
| | - Hervé Degand
- Louvain Institute of Biomolecular Science and Technology, UCLouvain, Place Croix du Sud 4-5, 1348, Louvain-la-Neuve, Belgium
| | - Damien Evrard
- Louvain Institute of Biomolecular Science and Technology, UCLouvain, Place Croix du Sud 4-5, 1348, Louvain-la-Neuve, Belgium
| | - Benoît Desguin
- Louvain Institute of Biomolecular Science and Technology, UCLouvain, Place Croix du Sud 4-5, 1348, Louvain-la-Neuve, Belgium
| | - Pierre Morsomme
- Louvain Institute of Biomolecular Science and Technology, UCLouvain, Place Croix du Sud 4-5, 1348, Louvain-la-Neuve, Belgium
| | - Jacob Biboy
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX, UK
| | - Joe Gray
- Biosciences Institute, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX, UK
| | - Karolina Mitusińska
- Tunneling Group, Biotechnology Centre, Silesian University of Technology, 44-100, Gliwice, Poland
| | - Artur Góra
- Tunneling Group, Biotechnology Centre, Silesian University of Technology, 44-100, Gliwice, Poland
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX, UK
| | - Patrice Soumillion
- Louvain Institute of Biomolecular Science and Technology, UCLouvain, Place Croix du Sud 4-5, 1348, Louvain-la-Neuve, Belgium.
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4
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Brissac T, Guyonnet C, Sadouni A, Hernández-Montoya A, Jacquemet E, Legendre R, Sismeiro O, Trieu-Cuot P, Lanotte P, Tazi A, Firon A. Coordinated regulation of osmotic imbalance by c-di-AMP shapes ß-lactam tolerance in Group B Streptococcus. MICROLIFE 2024; 5:uqae014. [PMID: 38993744 PMCID: PMC11238645 DOI: 10.1093/femsml/uqae014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 06/03/2024] [Accepted: 06/11/2024] [Indexed: 07/13/2024]
Abstract
Streptococcus agalactiae is among the few pathogens that have not developed resistance to ß-lactam antibiotics despite decades of clinical use. The molecular basis of this long-lasting susceptibility has not been investigated, and it is not known whether specific mechanisms constrain the emergence of resistance. In this study, we first report ß-lactam tolerance due to the inactivation of the c-di-AMP phosphodiesterase GdpP. Mechanistically, tolerance depends on antagonistic regulation by the repressor BusR, which is activated by c-di-AMP and negatively regulates ß-lactam susceptibility through the BusAB osmolyte transporter and the AmaP/Asp23/GlsB cell envelope stress complex. The BusR transcriptional response is synergistic with the simultaneous allosteric inhibition of potassium and osmolyte transporters by c-di-AMP, which individually contribute to low-level ß-lactam tolerance. Genome-wide transposon mutagenesis confirms the role of GdpP and highlights functional interactions between a lysozyme-like hydrolase, the KhpAB RNA chaperone and the protein S immunomodulator in the response of GBS to ß-lactam. Overall, we demonstrate that c-di-AMP acts as a turgor pressure rheostat, coordinating an integrated response at the transcriptional and post-translational levels to cell wall weakening caused by ß-lactam activity, and reveal additional mechanisms that could foster resistance.
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Affiliation(s)
- Terry Brissac
- Department of Microbiology, Biology of Gram-positive Pathogens, Institut Pasteur, Université Paris Cité, 75015, Paris, France
| | - Cécile Guyonnet
- Université Paris Cité, Institut Cochin, Institut National de la Santé et de la Recherche Médicale U1016, Centre National de la Recherche Scientifique UMR8104, Team Bacteria and Perinatality, 75015, Paris, France
- Department of Bacteriology, French National Reference Center for Streptococci, Assistance Publique-Hôpitaux de Paris Hôpitaux Universitaires Paris Centre, Hôpital Cochin, 75005, Paris, France
- Fédération Hospitalo-Universitaire Fighting Prematurity, 75005, Paris, France
| | - Aymane Sadouni
- Department of Microbiology, Biology of Gram-positive Pathogens, Institut Pasteur, Université Paris Cité, 75015, Paris, France
| | - Ariadna Hernández-Montoya
- Department of Microbiology, Biology of Gram-positive Pathogens, Institut Pasteur, Université Paris Cité, 75015, Paris, France
| | - Elise Jacquemet
- Institut Pasteur, Université Paris Cité, Bioinformatics and Biostatistics Hub, 75015 Paris, France
| | - Rachel Legendre
- Institut Pasteur, Université Paris Cité, Bioinformatics and Biostatistics Hub, 75015 Paris, France
| | - Odile Sismeiro
- Department of Microbiology, Biology of Gram-positive Pathogens, Institut Pasteur, Université Paris Cité, 75015, Paris, France
| | - Patrick Trieu-Cuot
- Department of Microbiology, Biology of Gram-positive Pathogens, Institut Pasteur, Université Paris Cité, 75015, Paris, France
| | - Philippe Lanotte
- Université de Tours, INRAE, UMR 1282 ISP, 3700, Tours, France
- CHRU de Tours, Service de Bactériologie-Virologie, 37044, Tours, France
| | - Asmaa Tazi
- Université Paris Cité, Institut Cochin, Institut National de la Santé et de la Recherche Médicale U1016, Centre National de la Recherche Scientifique UMR8104, Team Bacteria and Perinatality, 75015, Paris, France
- Department of Bacteriology, French National Reference Center for Streptococci, Assistance Publique-Hôpitaux de Paris Hôpitaux Universitaires Paris Centre, Hôpital Cochin, 75005, Paris, France
- Fédération Hospitalo-Universitaire Fighting Prematurity, 75005, Paris, France
| | - Arnaud Firon
- Department of Microbiology, Biology of Gram-positive Pathogens, Institut Pasteur, Université Paris Cité, 75015, Paris, France
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5
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Ryoo D, Hwang H, Gumbart JC. Thicket and Mesh: How the Outer Membrane Can Resist Tension Imposed by the Cell Wall. J Phys Chem B 2024; 128:5371-5377. [PMID: 38787347 PMCID: PMC11163421 DOI: 10.1021/acs.jpcb.3c08510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 05/07/2024] [Accepted: 05/09/2024] [Indexed: 05/25/2024]
Abstract
The cell envelope of Gram-negative bacteria is composed of an outer membrane (OM) and an inner membrane (IM) and a peptidoglycan cell wall (CW) between them. Combined with Braun's lipoprotein (Lpp), which connects the OM and the CW, and numerous membrane proteins that exist in both OM and IM, the cell envelope creates a mechanically stable environment that resists various physical and chemical perturbations to the cell, including turgor pressure caused by the solute concentration difference between the cytoplasm of the cell and the extracellular environment. Previous computational studies have explored how individual components (OM, IM, and CW) can resist turgor pressure although combinations of them have been less well studied. To that end, we constructed multiple OM-CW systems, including the Lpp connections with the CW under increasing degrees of strain. The results show that the OM can effectively resist the tension imposed by the CW, shrinking by only 3-5% in area even when the CW is stretched to 2.5× its relaxed area. The area expansion modulus of the system increases with increasing CW strain, although the OM remains a significant contributor to the envelope's mechanical stability. Additionally, we find that when the protein TolC is embedded in the OM, its stiffness increases.
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Affiliation(s)
- David Ryoo
- Interdisciplinary
Bioengineering Graduate Program, Georgia
Institute of Technology, Atlanta, Georgia 30332, United States
| | - Hyea Hwang
- School
of Materials Science and Engineering, Georgia
Institute of Technology, Atlanta, Georgia 30332, United States
| | - James C. Gumbart
- School
of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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6
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Bourqqia-Ramzi M, Mansilla-Guardiola J, Muñoz-Rodriguez D, Quarta E, Lombardo-Hernandez J, Murciano-Cespedosa A, Conejero-Meca FJ, Mateos González Á, Geuna S, Garcia-Esteban MT, Herrera-Rincon C. From the Microbiome to the Electrome: Implications for the Microbiota-Gut-Brain Axis. Int J Mol Sci 2024; 25:6233. [PMID: 38892419 PMCID: PMC11172653 DOI: 10.3390/ijms25116233] [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: 04/09/2024] [Revised: 05/30/2024] [Accepted: 05/31/2024] [Indexed: 06/21/2024] Open
Abstract
The gut microbiome plays a fundamental role in metabolism, as well as the immune and nervous systems. Microbial imbalance (dysbiosis) can contribute to subsequent physical and mental pathologies. As such, interest has been growing in the microbiota-gut-brain brain axis and the bioelectrical communication that could exist between bacterial and nervous cells. The aim of this study was to investigate the bioelectrical profile (electrome) of two bacterial species characteristic of the gut microbiome: a Proteobacteria Gram-negative bacillus Escherichia coli (E. coli), and a Firmicutes Gram-positive coccus Enterococcus faecalis (E. faecalis). We analyzed both bacterial strains to (i) validate the fluorescent probe bis-(1,3-dibutylbarbituric acid) trimethine oxonol, DiBAC4(3), as a reliable reporter of the changes in membrane potential (Vmem) for both bacteria; (ii) assess the evolution of the bioelectric profile throughout the growth of both strains; (iii) investigate the effects of two neural-type stimuli on Vmem changes: the excitatory neurotransmitter glutamate (Glu) and the inhibitory neurotransmitter γ-aminobutyric acid (GABA); (iv) examine the impact of the bioelectrical changes induced by neurotransmitters on bacterial growth, viability, and cultivability using absorbance, live/dead fluorescent probes, and viable counts, respectively. Our findings reveal distinct bioelectrical profiles characteristic of each bacterial species and growth phase. Importantly, neural-type stimuli induce Vmem changes without affecting bacterial growth, viability, or cultivability, suggesting a specific bioelectrical response in bacterial cells to neurotransmitter cues. These results contribute to understanding the bacterial response to external stimuli, with potential implications for modulating bacterial bioelectricity as a novel therapeutic target.
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Affiliation(s)
- Marwane Bourqqia-Ramzi
- Modeling, Data Analysis &Computational Tools for Biology Research Group, Biomathematics Unit, Department of Biodiversity, Ecology & Evolution, Faculty of Biological Sciences, Complutense University of Madrid, 28040 Madrid, Spain; (M.B.-R.); (J.M.-G.)
- Department of Neurosciences “Rita Levi Montalcini”, University of Turin, 10126 Turin, Italy
| | - Jesús Mansilla-Guardiola
- Modeling, Data Analysis &Computational Tools for Biology Research Group, Biomathematics Unit, Department of Biodiversity, Ecology & Evolution, Faculty of Biological Sciences, Complutense University of Madrid, 28040 Madrid, Spain; (M.B.-R.); (J.M.-G.)
- Unit of Microbiology, Department of Genetic, Physiology and Microbiology, Faculty of Biological Sciences, Complutense University of Madrid, 28040 Madrid, Spain
| | - David Muñoz-Rodriguez
- Modeling, Data Analysis &Computational Tools for Biology Research Group, Biomathematics Unit, Department of Biodiversity, Ecology & Evolution, Faculty of Biological Sciences, Complutense University of Madrid, 28040 Madrid, Spain; (M.B.-R.); (J.M.-G.)
| | - Elisa Quarta
- Modeling, Data Analysis &Computational Tools for Biology Research Group, Biomathematics Unit, Department of Biodiversity, Ecology & Evolution, Faculty of Biological Sciences, Complutense University of Madrid, 28040 Madrid, Spain; (M.B.-R.); (J.M.-G.)
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center “Guido Tarone”, University of Torino, 10126 Turin, Italy
| | - Juan Lombardo-Hernandez
- Modeling, Data Analysis &Computational Tools for Biology Research Group, Biomathematics Unit, Department of Biodiversity, Ecology & Evolution, Faculty of Biological Sciences, Complutense University of Madrid, 28040 Madrid, Spain; (M.B.-R.); (J.M.-G.)
| | - Antonio Murciano-Cespedosa
- Modeling, Data Analysis &Computational Tools for Biology Research Group, Biomathematics Unit, Department of Biodiversity, Ecology & Evolution, Faculty of Biological Sciences, Complutense University of Madrid, 28040 Madrid, Spain; (M.B.-R.); (J.M.-G.)
- Neuro-Computing and Neuro-Robotics Research Group, Neural Plasticity Research Group Instituto Investigación Sanitaria Hospital Clínico San Carlos (IdISSC), Complutense University of Madrid, 28040 Madrid, Spain
| | - Francisco José Conejero-Meca
- Modeling, Data Analysis &Computational Tools for Biology Research Group, Biomathematics Unit, Department of Biodiversity, Ecology & Evolution, Faculty of Biological Sciences, Complutense University of Madrid, 28040 Madrid, Spain; (M.B.-R.); (J.M.-G.)
| | - Álvaro Mateos González
- Modeling, Data Analysis &Computational Tools for Biology Research Group, Biomathematics Unit, Department of Biodiversity, Ecology & Evolution, Faculty of Biological Sciences, Complutense University of Madrid, 28040 Madrid, Spain; (M.B.-R.); (J.M.-G.)
- University of Michigan-Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Stefano Geuna
- Department of Clinical and Biological Sciences, Cavalieri Ottolenghi Neuroscience Institute, University of Turin, Ospedale San Luigi, 10043 Turin, Italy
| | - María Teresa Garcia-Esteban
- Unit of Microbiology, Department of Genetic, Physiology and Microbiology, Faculty of Biological Sciences, Complutense University of Madrid, 28040 Madrid, Spain
| | - Celia Herrera-Rincon
- Modeling, Data Analysis &Computational Tools for Biology Research Group, Biomathematics Unit, Department of Biodiversity, Ecology & Evolution, Faculty of Biological Sciences, Complutense University of Madrid, 28040 Madrid, Spain; (M.B.-R.); (J.M.-G.)
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7
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Lee J, Jha K, Harper CE, Zhang W, Ramsukh M, Bouklas N, Dörr T, Chen P, Hernandez CJ. Determining the Young's Modulus of the Bacterial Cell Envelope. ACS Biomater Sci Eng 2024; 10:2956-2966. [PMID: 38593061 DOI: 10.1021/acsbiomaterials.4c00105] [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] [Indexed: 04/11/2024]
Abstract
Bacteria experience substantial physical forces in their natural environment, including forces caused by osmotic pressure, growth in constrained spaces, and fluid shear. The cell envelope is the primary load-carrying structure of bacteria, but the mechanical properties of the cell envelope are poorly understood; reports of Young's modulus of the cell envelope of Escherichia coli range from 2 to 18 MPa. We developed a microfluidic system to apply mechanical loads to hundreds of bacteria at once and demonstrated the utility of the approach for evaluating whole-cell stiffness. Here, we extend this technique to determine Young's modulus of the cell envelope of E. coli and of the pathogens Vibrio cholerae and Staphylococcus aureus. An optimization-based inverse finite element analysis was used to determine the cell envelope Young's modulus from observed deformations. The Young's modulus values of the cell envelope were 2.06 ± 0.04 MPa for E. coli, 0.84 ± 0.02 MPa for E. coli treated with a chemical (A22) known to reduce cell stiffness, 0.12 ± 0.03 MPa for V. cholerae, and 1.52 ± 0.06 MPa for S. aureus (mean ± SD). The microfluidic approach allows examination of hundreds of cells at once and is readily applied to Gram-negative and Gram-positive organisms as well as rod-shaped and cocci cells, allowing further examination of the structural causes behind differences in cell envelope Young's modulus among bacterial species and strains.
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Affiliation(s)
- Junsung Lee
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Karan Jha
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Christine E Harper
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York 14853, United States
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Wenyao Zhang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Malissa Ramsukh
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Nikolaos Bouklas
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Tobias Dörr
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York 14853, United States
- Department of Microbiology, Cornell University, Ithaca, New York 14853, United States
- Cornell Institute of Host-Microbe Interactions and Disease, Cornell University, Ithaca, New York 14853, United States
| | - Peng Chen
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Christopher J Hernandez
- Departments of Bioengineering and Therapeutic Sciences and Orthopaedic Surgery, UC San Francisco, California 94143, United States
- Chan Zuckerberg Biohub, San Francisco, California 94158, United States
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8
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Müller N, Kollert M, Trampuz A, Gonzalez Moreno M. Efficacy of different bioactive glass S53P4 formulations in biofilm eradication and the impact of pH and osmotic pressure. Colloids Surf B Biointerfaces 2024; 239:113940. [PMID: 38744081 DOI: 10.1016/j.colsurfb.2024.113940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 04/16/2024] [Accepted: 04/30/2024] [Indexed: 05/16/2024]
Abstract
AIM The challenging properties of biofilm-associated infections and the rise of multidrug-resistant bacteria are prompting the exploration of alternative treatment options. This study investigates the efficacy of different bioactive glass (BAG) formulations - alone or combined with vancomycin - to eradicate biofilm. Further, we study the influence of BAG on pH and osmotic pressure as important factors limiting bacterial growth. METHOD Different BAG S53P4 formulations were used for this study, including (a) powder (<45 μm), (b) granules (500-800 µm), (c) a cone-shaped scaffold and (d) two putty formulations containing granules with no powder (putty A) or with additional powder (putty B) bound together by a synthetic binder. Inert glass beads (1.0-1.3 mm) were included as control. All formulations were tested in a concentration of 1750 mg/ml in Müller-Hinton-Broth against methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE). Vancomycin was tested at the minimum-inhibitory concentration for each strain. Changes in pH and osmolality over time were assessed at 0 h, 24 h, 72 h and 168 h. RESULTS All tested BAG formulations showed antibiofilm activity against MRSA and MRSE. Powder and putty B were the most effective formulations suppressing biofilm leading to its complete eradication after up to 168 h of co-incubation, followed by granules, scaffold and putty A. In general, MRSE appeared to be more susceptible to bioactive glass compared to MRSA. The addition of vancomycin had no substantial impact on biofilm eradication. We observed a positive correlation between a higher pH and higher antibiofilm activity. CONCLUSIONS BAG S53P4 has demonstrated efficient biofilm antibiofilm activity against MRSA and MRSE, especially in powder-containing formulations, resulting in complete eradication of biofilm. Our data indicate neither remarkable increase nor decrease in antimicrobial efficacy with addition of vancomycin. Moreover, high pH appears to have a direct antimicrobial impact; the role of high osmolality needs further investigation.
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Affiliation(s)
- Nele Müller
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Center for Regenerative Therapies (BCRT), Charitéplatz 1, Berlin 10117, Germany
| | - Matthias Kollert
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Center for Regenerative Therapies (BCRT), Charitéplatz 1, Berlin 10117, Germany; Department of Health Sciences and Technology, ETH Zurich, Zurich 8092, Switzerland; Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Julius Wolff Institute, Augustenburger Platz 1, Berlin 13353, Germany
| | - Andrej Trampuz
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Center for Regenerative Therapies (BCRT), Charitéplatz 1, Berlin 10117, Germany; Center for Musculoskeletal Surgery, Charité-Universitätsmedizin Berlin, corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Augustenburger Platz 1, Berlin 13353, Germany.
| | - Mercedes Gonzalez Moreno
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Center for Regenerative Therapies (BCRT), Charitéplatz 1, Berlin 10117, Germany; Center for Musculoskeletal Surgery, Charité-Universitätsmedizin Berlin, corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Augustenburger Platz 1, Berlin 13353, Germany
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9
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Basan M, Mukherjee A, Huang Y, Oh S, Sanchez C, Chang YF, Liu X, Bradshaw G, Benites N, Paulsson J, Kirschner M, Sung Y, Elgeti J. Homeostasis of cytoplasmic crowding by cell wall fluidization and ribosomal counterions. RESEARCH SQUARE 2024:rs.3.rs-4138690. [PMID: 38699329 PMCID: PMC11065075 DOI: 10.21203/rs.3.rs-4138690/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
In bacteria, algae, fungi, and plant cells, the wall must expand in concert with cytoplasmic biomass production, otherwise cells would experience toxic molecular crowding1,2 or lyse. But how cells achieve expansion of this complex biomaterial in coordination with biosynthesis of macromolecules in the cytoplasm remains unexplained3, although recent works have revealed that these processes are indeed coupled4,5. Here, we report a striking increase of turgor pressure with growth rate in E. coli, suggesting that the speed of cell wall expansion is controlled via turgor. Remarkably, despite this increase in turgor pressure, cellular biomass density remains constant across a wide range of growth rates. By contrast, perturbations of turgor pressure that deviate from this scaling directly alter biomass density. A mathematical model based on cell wall fluidization by cell wall endopeptidases not only explains these apparently confounding observations but makes surprising quantitative predictions that we validated experimentally. The picture that emerges is that turgor pressure is directly controlled via counterions of ribosomal RNA. Elegantly, the coupling between rRNA and turgor pressure simultaneously coordinates cell wall expansion across a wide range of growth rates and exerts homeostatic feedback control on biomass density. This mechanism may regulate cell wall biosynthesis from microbes to plants and has important implications for the mechanism of action of antibiotics6.
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10
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Valiei A, Bryche JF, Canva M, Charette PG, Moraes C, Hill RJ, Tufenkji N. Effects of Surface Topography and Cellular Biomechanics on Nanopillar-Induced Bactericidal Activity. ACS APPLIED MATERIALS & INTERFACES 2024; 16:9614-9625. [PMID: 38378485 DOI: 10.1021/acsami.3c09552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2024]
Abstract
Bacteria are mechanically resistant biological structures that can sustain physical stress. Experimental data, however, have shown that high-aspect-ratio nanopillars deform bacterial cells upon contact. If the deformation is sufficiently large, it lyses the bacterial cell wall, ultimately leading to cell death. This has prompted a novel strategy, known as mechano-bactericide technology, to fabricate antibacterial surfaces. Although adhesion forces were originally proposed as the driving force for mechano-bactericidal action, it has been recently shown that external forces, such as capillary forces arising from an air-water interface at bacterial surfaces, produce sufficient loads to rapidly kill bacteria on nanopillars. This discovery highlights the need to theoretically examine how bacteria respond to external loads and to ascertain the key factors. In this study, we developed a finite element model approximating bacteria as elastic shells filled with cytoplasmic fluid brought into contact with an individual nanopillar or nanopillar array. This model elucidates that bacterial killing caused by external forces on nanopillars is influenced by surface topography and cell biomechanical variables, including the density and arrangement of nanopillars, in addition to the cell wall thickness and elastic modulus. Considering that surface topography is an important design parameter, we performed experiments using nanopillar arrays with precisely controlled nanopillar diameters and spacing. Consistent with model predictions, these demonstrate that nanopillars with a larger spacing increase bacterial susceptibility to mechanical puncture. The results provide salient insights into mechano-bactericidal activity and identify key design parameters for implementing this technology.
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Affiliation(s)
- Amin Valiei
- Department of Chemical Engineering, McGill University, Montreal, Québec H3A 0C5, Canada
| | - Jean-François Bryche
- Laboratoire Nanotechnologies Nanosystèmes (LN2)-IRL3463, CNRS, Université de Sherbrooke, Universitè Grenoble Alpes, École Centrale de Lyon, INSA Lyon, Sherbrooke, Québec J1K 0A5, Canada
- Institut Interdisciplinaire d'Innovation Technologique (3IT), Université de Sherbrooke, 3000 Boulevard de l'Université, Sherbrooke, Québec J1K OA5, Canada
| | - Michael Canva
- Laboratoire Nanotechnologies Nanosystèmes (LN2)-IRL3463, CNRS, Université de Sherbrooke, Universitè Grenoble Alpes, École Centrale de Lyon, INSA Lyon, Sherbrooke, Québec J1K 0A5, Canada
- Institut Interdisciplinaire d'Innovation Technologique (3IT), Université de Sherbrooke, 3000 Boulevard de l'Université, Sherbrooke, Québec J1K OA5, Canada
| | - Paul G Charette
- Laboratoire Nanotechnologies Nanosystèmes (LN2)-IRL3463, CNRS, Université de Sherbrooke, Universitè Grenoble Alpes, École Centrale de Lyon, INSA Lyon, Sherbrooke, Québec J1K 0A5, Canada
- Institut Interdisciplinaire d'Innovation Technologique (3IT), Université de Sherbrooke, 3000 Boulevard de l'Université, Sherbrooke, Québec J1K OA5, Canada
| | - Christopher Moraes
- Department of Chemical Engineering, McGill University, Montreal, Québec H3A 0C5, Canada
- Department of Biomedical Engineering, McGill University, Montreal, Québec H3A 0C5, Canada
- Goodman Cancer Research Center, McGill University, Montreal, Québec H3A 0G4, Canada
| | - Reghan J Hill
- Department of Chemical Engineering, McGill University, Montreal, Québec H3A 0C5, Canada
| | - Nathalie Tufenkji
- Department of Chemical Engineering, McGill University, Montreal, Québec H3A 0C5, Canada
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11
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Eskandarian HA, Chen YX, Toniolo C, Belardinelli JM, Palcekova Z, Hom L, Ashby PD, Fantner GE, Jackson M, McKinney JD, Javid B. Mechanical morphotype switching as an adaptive response in mycobacteria. SCIENCE ADVANCES 2024; 10:eadh7957. [PMID: 38170768 PMCID: PMC10776010 DOI: 10.1126/sciadv.adh7957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 12/01/2023] [Indexed: 01/05/2024]
Abstract
Invading microbes face a myriad of cidal mechanisms of phagocytes that inflict physical damage to microbial structures. How intracellular bacterial pathogens adapt to these stresses is not fully understood. Here, we report the discovery of a virulence mechanism by which changes to the mechanical stiffness of the mycobacterial cell surface confer refraction to killing during infection. Long-term time-lapse atomic force microscopy was used to reveal a process of "mechanical morphotype switching" in mycobacteria exposed to host intracellular stress. A "soft" mechanical morphotype switch enhances tolerance to intracellular macrophage stress, including cathelicidin. Both pharmacologic treatment, with bedaquiline, and a genetic mutant lacking uvrA modified the basal mechanical state of mycobacteria into a soft mechanical morphotype, enhancing survival in macrophages. Our study proposes microbial cell mechanical adaptation as a critical axis for surviving host-mediated stressors.
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Affiliation(s)
- Haig Alexander Eskandarian
- Division of Experimental Medicine, University of California San Francisco, San Francisco, CA 94143, USA
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Yu-Xiang Chen
- Division of Experimental Medicine, University of California San Francisco, San Francisco, CA 94143, USA
| | - Chiara Toniolo
- School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Juan M. Belardinelli
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523-1682, USA
| | - Zuzana Palcekova
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523-1682, USA
| | - Lesley Hom
- Division of Experimental Medicine, University of California San Francisco, San Francisco, CA 94143, USA
| | - Paul D. Ashby
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Georg E. Fantner
- School of Engineering, Swiss Federal Institute of Technology (EPFL), 1015 Lausanne, Switzerland
| | - Mary Jackson
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523-1682, USA
| | - John D. McKinney
- School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Babak Javid
- Division of Experimental Medicine, University of California San Francisco, San Francisco, CA 94143, USA
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12
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Mason G, Footer MJ, Rojas ER. Mechanosensation induces persistent bacterial growth during bacteriophage predation. mBio 2023; 14:e0276622. [PMID: 37909775 PMCID: PMC10746221 DOI: 10.1128/mbio.02766-22] [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: 09/30/2022] [Accepted: 09/27/2023] [Indexed: 11/03/2023] Open
Abstract
IMPORTANCE Bacteria and bacteriophage form one of the most important predator-prey relationships on earth, yet how the long-term stability of this ecological interaction is achieved is unclear. Here, we demonstrate that Escherichia coli can rapidly grow during bacteriophage predation if they are doing so in spatially confined environments. This discovery revises our understanding of bacteria-bacteriophage population dynamics in many real-world environments where bacteria grow in confinement, such as the gut and the soil. Additionally, this result has clear implications for the potential of bacteriophage therapy and the role of mechanosensation during bacterial pathogenesis.
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Affiliation(s)
- Guy Mason
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, New York, USA
| | - Matthew J. Footer
- Department of Biology, Howard Hughes Medical Institute, University of Washington, Seattle, Washington, USA
| | - Enrique R. Rojas
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, New York, USA
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13
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Kurisu M, Imai M. Concepts of a synthetic minimal cell: Information molecules, metabolic pathways, and vesicle reproduction. Biophys Physicobiol 2023; 21:e210002. [PMID: 38803330 PMCID: PMC11128301 DOI: 10.2142/biophysico.bppb-v21.0002] [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: 07/05/2023] [Accepted: 12/15/2023] [Indexed: 05/29/2024] Open
Abstract
How do the living systems emerge from non-living molecular assemblies? What physical and chemical principles supported the process? To address these questions, a promising strategy is to artificially reconstruct living cells in a bottom-up way. Recently, the authors developed the "synthetic minimal cell" system showing recursive growth and division cycles, where the concepts of information molecules, metabolic pathways, and cell reproduction were artificially and concisely redesigned with the vesicle-based system. We intentionally avoided using the sophisticated molecular machinery of the biological cells and tried to redesign the cells in the simplest forms. This review focuses on the similarities and differences between the biological cells and our synthetic minimal cell concerning each concept of cells. Such comparisons between natural and artificial cells will provide insights on how the molecules should be assembled to create living systems to the wide readers in the field of synthetic biology, artificial cells, and protocells research. This review article is an extended version of the Japanese article "Growth and division of vesicles coupled with information molecules," published in SEIBUTSU-BUTSURI vol. 61, p. 378-381 (2021).
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Affiliation(s)
- Minoru Kurisu
- Department of Physics, Graduate School of Science, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Masayuki Imai
- Department of Physics, Graduate School of Science, Tohoku University, Sendai, Miyagi 980-8578, Japan
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14
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Babayan A, Vassilian A, Trchounian K. Osmotic stress as a factor for regulating E. coli hydrogenase activity and enhancing H 2 production during mixed carbon sources fermentation. AIMS Microbiol 2023; 9:724-737. [PMID: 38173976 PMCID: PMC10758574 DOI: 10.3934/microbiol.2023037] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 10/18/2023] [Accepted: 10/27/2023] [Indexed: 01/05/2024] Open
Abstract
Escherichia coli performs mixed-acid fermentation and produces molecular hydrogen (H2) via reversible hydrogenases (Hyd). H2 producing activity was investigated during hyper- and hypo-osmotic stress conditions when a mixture of carbon sources (glucose and glycerol) was fermented at different pHs. Hyper-osmotic stress decreased H2 production rate (VH2) ~30 % in wild type at pH 7.5 when glucose was supplemented, while addition of formate stimulated VH2 ~45% compared to hypo-stress conditions. Only in hyfG in formate assays was VH2 inhibited ~25% compared to hypo-stress conditions. In hypo-stress conditions addition of glycerol increased VH2 ~2 and 3 fold in hybC and hyfG mutants, respectively, compared to wild type. At pH 6.5 hyper-osmotic stress stimulated VH2 ~2 fold in all strains except hyaB mutant when glucose was supplemented, while in formate assays significant stimulation (~3 fold) was determined in hybC mutant. At pH 5.5 hyper-osmotic stress inhibited VH2 ~30% in wild type when glucose was supplemented, but in formate assays it was stimulated in all strains except hyfG. Taken together, it can be concluded that, depending on external pH and absence of Hyd enzymes in stationary-phase-grown osmotically stressed E. coli cells, H2 production can be stimulated significantly which can be applied in developing H2 production biotechnology.
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Affiliation(s)
- Anush Babayan
- Department of Biochemistry, Microbiology and Biotechnology, Faculty of Biology, Yerevan State University, 0025 Yerevan, Armenia
- Scientific-Research Institute of Biology, Faculty of Biology, Yerevan State University, 0025 Yerevan, Armenia
- Microbial Biotechnologies and Biofuel Innovation Center, Yerevan State University, 0025 Yerevan, Armenia
| | - Anait Vassilian
- Scientific-Research Institute of Biology, Faculty of Biology, Yerevan State University, 0025 Yerevan, Armenia
- Department of Ecology and Nature Protection, Faculty of Biology, Yerevan State University, 0025 Yerevan, Armenia
| | - Karen Trchounian
- Department of Biochemistry, Microbiology and Biotechnology, Faculty of Biology, Yerevan State University, 0025 Yerevan, Armenia
- Scientific-Research Institute of Biology, Faculty of Biology, Yerevan State University, 0025 Yerevan, Armenia
- Microbial Biotechnologies and Biofuel Innovation Center, Yerevan State University, 0025 Yerevan, Armenia
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15
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Mukherjee A, Huang Y, Oh S, Sanchez C, Chang YF, Liu X, Bradshaw GA, Benites NC, Paulsson J, Kirschner MW, Sung Y, Elgeti J, Basan M. A universal mechanism of biomass density homeostasis via ribosomal counterions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.31.555748. [PMID: 37808635 PMCID: PMC10557573 DOI: 10.1101/2023.08.31.555748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
In all growing cells, the cell envelope must expand in concert with cytoplasmic biomass to prevent lysis or molecular crowding. The complex cell wall of microbes and plants makes this challenge especially daunting and it unclear how cells achieve this coordination. Here, we uncover a striking linear increase of cytoplasmic pressure with growth rate in E. coli. Remarkably, despite this increase in turgor pressure with growth rate, cellular biomass density was constant across a wide range of growth rates. In contrast, perturbing pressure away from this scaling directly affected biomass density. A mathematical model, in which endopeptidase-mediated cell wall fluidization enables turgor pressure to set the pace of cellular volume expansion, not only explains these confounding observations, but makes several surprising quantitative predictions that we validated experimentally. The picture that emerges is that changes in turgor pressure across growth rates are mediated by counterions of ribosomal RNA. Profoundly, the coupling between rRNA and cytoplasmic pressure simultaneously coordinates cell wall expansion across growth rates and exerts homeostatic feedback control on biomass density. Because ribosome content universally scales with growth rate in fast growing cells, this universal mechanism may control cell wall biosynthesis in microbes and plants and drive the expansion of ribosome-addicted tumors that can exert substantial mechanical forces on their environment.
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16
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Lough W, Weibel DB, Spagnolie SE. Self-buckling and self-writhing of semi-flexible microorganisms. SOFT MATTER 2023; 19:7349-7357. [PMID: 37740382 DOI: 10.1039/d3sm00572k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/24/2023]
Abstract
The twisting and writhing of a cell body and associated mechanical stresses is an underappreciated constraint on microbial self-propulsion. Multi-flagellated bacteria can even buckle and writhe under their own activity as they swim through a viscous fluid. New equilibrium configurations and steady-state dynamics then emerge which depend on the organism's mechanical properties and on the oriented distribution of flagella along its surface. Modeling the cell body as a semi-flexible Kirchhoff rod and coupling the mechanics to a flagellar orientation field, we derive the Euler-Poincaré equations governing the dynamics of the system, and rationalize experimental observations of buckling and writhing of elongated swarmer cells of the bacterium Proteus mirabilis. A sequence of bifurcations is identified as the body is made more compliant, due to both buckling and torsional instabilities. These studies highlight a practical requirement for the stiffness of bacteria below which self-buckling occurs and cell motility becomes ineffective.
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Affiliation(s)
- Wilson Lough
- Department of Physics, University of Wisconsin-Madison, Madison, WI 53706, USA.
| | - Douglas B Weibel
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Saverio E Spagnolie
- Department of Mathematics, University of Wisconsin-Madison, 480 Lincoln Dr, Madison, WI 53706, USA
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
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17
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Kadeřábková N, Mahmood AJS, Furniss RCD, Mavridou DAI. Making a chink in their armor: Current and next-generation antimicrobial strategies against the bacterial cell envelope. Adv Microb Physiol 2023; 83:221-307. [PMID: 37507160 PMCID: PMC10517717 DOI: 10.1016/bs.ampbs.2023.05.003] [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] [Indexed: 07/30/2023]
Abstract
Gram-negative bacteria are uniquely equipped to defeat antibiotics. Their outermost layer, the cell envelope, is a natural permeability barrier that contains an array of resistance proteins capable of neutralizing most existing antimicrobials. As a result, its presence creates a major obstacle for the treatment of resistant infections and for the development of new antibiotics. Despite this seemingly impenetrable armor, in-depth understanding of the cell envelope, including structural, functional and systems biology insights, has promoted efforts to target it that can ultimately lead to the generation of new antibacterial therapies. In this article, we broadly overview the biology of the cell envelope and highlight attempts and successes in generating inhibitors that impair its function or biogenesis. We argue that the very structure that has hampered antibiotic discovery for decades has untapped potential for the design of novel next-generation therapeutics against bacterial pathogens.
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Affiliation(s)
- Nikol Kadeřábková
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, United States
| | - Ayesha J S Mahmood
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, United States
| | - R Christopher D Furniss
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Despoina A I Mavridou
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, United States; John Ring LaMontagne Center for Infectious Diseases, The University of Texas at Austin, Austin, TX, United States.
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18
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Kitahara Y, van Teeffelen S. Bacterial growth - from physical principles to autolysins. Curr Opin Microbiol 2023; 74:102326. [PMID: 37279609 DOI: 10.1016/j.mib.2023.102326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 04/11/2023] [Accepted: 04/13/2023] [Indexed: 06/08/2023]
Abstract
For bacteria to increase in size, they need to enzymatically expand their cell envelopes, and more concretely their peptidoglycan cell wall. A major task of growth is to increase intracellular space for the accumulation of macromolecules, notably proteins, RNA, and DNA. Here, we review recent progress in our understanding of how cells coordinate envelope growth with biomass growth, focusing on elongation of rod-like bacteria. We first describe the recent discovery that surface area, but not cell volume, increases in proportion to mass growth. We then discuss how this relation could possibly be implemented mechanistically, reviewing the role of envelope insertion for envelope growth. Since cell-wall expansion requires the well-controlled activity of autolysins, we finally review recent progress in our understanding of autolysin regulation.
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Affiliation(s)
- Yuki Kitahara
- Département de Microbiologie, Infectiologie, et Immunologie, Faculté de Médecine, Université de Montréal, Montréal, QC, Canada
| | - Sven van Teeffelen
- Département de Microbiologie, Infectiologie, et Immunologie, Faculté de Médecine, Université de Montréal, Montréal, QC, Canada.
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19
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Awada Z, Nedjar B. On a finite strain modeling of growth in budding yeast. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2023; 39:e3710. [PMID: 37070287 DOI: 10.1002/cnm.3710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 01/05/2023] [Accepted: 04/02/2023] [Indexed: 06/07/2023]
Abstract
Cell's ability to proliferate constitutes one of the most defining features of life. The proliferation occurs through a succession of events; the cell cycle, whereby the cell grows and divides. In this paper, focus is made on the growth step and we deal specifically with Saccharomyces cerevisiae yeast that reproduces by budding. For this, we develop a theoretical model to predict the growth powered by the turgor pressure. This cell is herein considered as a thin-walled structure with almost axisymmetrical shape. Due to its soft nature, the large deformation range is a priori assumed through a finite growth modeling framework. The used kinematics is based on the multiplicative decomposition of the deformation gradient into an elastically reversible part and a growth part. Constitutive equations are proposed where use is made of hyperelasticity together with a local evolution equation, this latter to describe the way growth takes place. In particular, two essential parameters are involved: a stress-like threshold, and a characteristic time. The developed model is extended to a shell approach as well. In a finite element context, representative numerical simulations examining stress-dependent growth are given and a parametric study is conducted to show the sensitivity with respect to the above mentioned parameters. Finally, a suggestion for natural contractile ring modeling closes this study.
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Affiliation(s)
- Zeinab Awada
- MAST (MAterial and STructures), EMGCU (Expérimenation en Modélisation pour le Génic Civil et Urdain), Université Gustave Eiffel, Marne-la-Vallée cedex 2, France
| | - Boumediene Nedjar
- MAST (MAterial and STructures), EMGCU (Expérimenation en Modélisation pour le Génic Civil et Urdain), Université Gustave Eiffel, Marne-la-Vallée cedex 2, France
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20
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Figueroa-Cuilan WM, Irazoki O, Feeley M, Smith E, Nguyen T, Cava F, Goley ED. Quantitative analysis of morphogenesis and growth dynamics in an obligate intracellular bacterium. Mol Biol Cell 2023; 34:ar69. [PMID: 37017481 PMCID: PMC10295487 DOI: 10.1091/mbc.e23-01-0023] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 03/23/2023] [Accepted: 03/29/2023] [Indexed: 04/06/2023] Open
Abstract
Obligate intracellular bacteria of the order Rickettsiales include important human pathogens. However, our understanding of the biology of Rickettsia species is limited by challenges imposed by their obligate intracellular lifestyle. To overcome this roadblock, we developed methods to assess cell wall composition, growth, and morphology of Rickettsia parkeri, a human pathogen in the spotted fever group of the Rickettsia genus. Analysis of the cell wall of R. parkeri revealed unique features that distinguish it from free-living alphaproteobacteria. Using a novel fluorescence microscopy approach, we quantified R. parkeri morphology in live host cells and found that the fraction of the population undergoing cell division decreased over the course of infection. We further demonstrated the feasibility of localizing fluorescence fusions, for example, to the cell division protein ZapA, in live R. parkeri for the first time. To evaluate population growth kinetics, we developed an imaging-based assay that improves on the throughput and resolution of other methods. Finally, we applied these tools to quantitatively demonstrate that the actin homologue MreB is required for R. parkeri growth and rod shape. Collectively, a toolkit was developed of high-throughput, quantitative tools to understand growth and morphogenesis of R. parkeri that is translatable to other obligate intracellular bacteria.
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Affiliation(s)
- Wanda M. Figueroa-Cuilan
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205-2185
| | - Oihane Irazoki
- Laboratory for Molecular Infection Medicine, Umeå Center for Microbial Research, Department of Molecular Biology, Umeå University, SE-901 87, Umeå, Sweden
| | - Marissa Feeley
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205-2185
| | - Erika Smith
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205-2185
| | - Trung Nguyen
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205-2185
| | - Felipe Cava
- Laboratory for Molecular Infection Medicine, Umeå Center for Microbial Research, Department of Molecular Biology, Umeå University, SE-901 87, Umeå, Sweden
| | - Erin D. Goley
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205-2185
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21
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Willdigg JR, Patel Y, Helmann JD. A Decrease in Fatty Acid Synthesis Rescues Cells with Limited Peptidoglycan Synthesis Capacity. mBio 2023; 14:e0047523. [PMID: 37017514 PMCID: PMC10128001 DOI: 10.1128/mbio.00475-23] [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: 02/24/2023] [Accepted: 03/13/2023] [Indexed: 04/06/2023] Open
Abstract
Proper synthesis and maintenance of a multilayered cell envelope are critical for bacterial fitness. However, whether mechanisms exist to coordinate synthesis of the membrane and peptidoglycan layers is unclear. In Bacillus subtilis, synthesis of peptidoglycan (PG) during cell elongation is mediated by an elongasome complex acting in concert with class A penicillin-binding proteins (aPBPs). We previously described mutant strains limited in their capacity for PG synthesis due to a loss of aPBPs and an inability to compensate by upregulation of elongasome function. Growth of these PG-limited cells can be restored by suppressor mutations predicted to decrease membrane synthesis. One suppressor mutation leads to an altered function repressor, FapR*, that functions as a super-repressor and leads to decreased transcription of fatty acid synthesis (FAS) genes. Consistent with fatty acid limitation mitigating cell wall synthesis defects, inhibition of FAS by cerulenin also restored growth of PG-limited cells. Moreover, cerulenin can counteract the inhibitory effect of β-lactams in some strains. These results imply that limiting PG synthesis results in impaired growth, in part, due to an imbalance of PG and cell membrane synthesis and that B. subtilis lacks a robust physiological mechanism to reduce membrane synthesis when PG synthesis is impaired. IMPORTANCE Understanding how a bacterium coordinates cell envelope synthesis is essential to fully appreciate how bacteria grow, divide, and resist cell envelope stresses, such as β-lactam antibiotics. Balanced synthesis of the peptidoglycan cell wall and the cell membrane is critical for cells to maintain shape and turgor pressure and to resist external cell envelope threats. Using Bacillus subtilis, we show that cells deficient in peptidoglycan synthesis can be rescued by compensatory mutations that decrease the synthesis of fatty acids. Further, we show that inhibiting fatty acid synthesis with cerulenin is sufficient to restore growth of cells deficient in peptidoglycan synthesis. Understanding the coordination of cell wall and membrane synthesis may provide insights relevant to antimicrobial treatment.
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Affiliation(s)
| | - Yesha Patel
- Department of Microbiology, Cornell University, Ithaca, New York, USA
| | - John D. Helmann
- Department of Microbiology, Cornell University, Ithaca, New York, USA
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22
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Ali O, Cheddadi I, Landrein B, Long Y. Revisiting the relationship between turgor pressure and plant cell growth. THE NEW PHYTOLOGIST 2023; 238:62-69. [PMID: 36527246 DOI: 10.1111/nph.18683] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
Growth is central to plant morphogenesis. Plant cells are encased in rigid cell walls, and they must overcome physical confinement to grow to specific sizes and shapes. Cell wall tension and turgor pressure are the main mechanical components impacting plant cell growth. Cell wall mechanics has been the focus of most plant biomechanical studies, and turgor pressure was often considered as a constant and largely passive component. Nevertheless, it is increasingly accepted that turgor pressure plays a significant role in plant growth. Numerous theoretical and experimental studies suggest that turgor pressure can be both spatially inhomogeneous and actively modulated during morphogenesis. Here, we revisit the pressure-growth relationship by reviewing recent advances in investigating the interactions between cellular/tissular pressure and growth.
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Affiliation(s)
- Olivier Ali
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, INRIA, Lyon Cedex 07, 69364, France
| | - Ibrahim Cheddadi
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, INRIA, Lyon Cedex 07, 69364, France
- Univ. Grenoble Alpes, CNRS, UMR 5525, VetAgro Sup, Grenoble INP, TIMC, 38000, Grenoble, France
| | - Benoit Landrein
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRAE, INRIA, Lyon Cedex 07, 69364, France
| | - Yuchen Long
- Department of Biological Sciences, The National University of Singapore, Singapore, 117543, Singapore
- Mechanobiology Institute, The National University of Singapore, Singapore, 117411, Singapore
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23
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Brauer AM, Shi H, Levin PA, Huang KC. Physiological and regulatory convergence between osmotic and nutrient stress responses in microbes. Curr Opin Cell Biol 2023; 81:102170. [PMID: 37119759 PMCID: PMC10493190 DOI: 10.1016/j.ceb.2023.102170] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 03/09/2023] [Accepted: 03/20/2023] [Indexed: 05/01/2023]
Abstract
Bacterial cells are regularly confronted with simultaneous changes in environmental nutrient supply and osmolarity. Despite the importance of osmolarity and osmoregulation in bacterial physiology, the relationship between the cellular response to osmotic perturbations and other stresses has remained largely unexplored. Bacteria cultured in hyperosmotic conditions and bacteria experiencing nutrient stress exhibit similar physiological changes, including metabolic shutdown, increased protein instability, dehydration, and condensation of chromosomal DNA. In this review, we highlight overlapping molecular players between osmotic and nutrient stresses. These connections between two seemingly disparate stress response pathways reinforce the importance of central carbon metabolism as a control point for diverse aspects of homeostatic regulation. We identify important open questions for future research, emphasizing the pressing need to develop and exploit new methods for probing how osmolarity affects phylogenetically diverse species.
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Affiliation(s)
- Adrienne M Brauer
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Handuo Shi
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - Petra Anne Levin
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA.
| | - Kerwyn Casey Huang
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Bioengineering, Stanford University, Stanford, CA 94305, USA; Chan Zuckerberg Biohub, San Francisco, CA 94158, USA.
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24
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Kurisu M, Katayama R, Sakuma Y, Kawakatsu T, Walde P, Imai M. Synthesising a minimal cell with artificial metabolic pathways. Commun Chem 2023; 6:56. [PMID: 36977828 PMCID: PMC10050237 DOI: 10.1038/s42004-023-00856-y] [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: 12/07/2022] [Accepted: 03/15/2023] [Indexed: 03/30/2023] Open
Abstract
A "synthetic minimal cell" is considered here as a cell-like artificial vesicle reproduction system in which a chemical and physico-chemical transformation network is regulated by information polymers. Here we synthesise such a minimal cell consisting of three units: energy production, information polymer synthesis, and vesicle reproduction. Supplied ingredients are converted to energy currencies which trigger the synthesis of an information polymer, where the vesicle membrane plays the role of a template. The information polymer promotes membrane growth. By tuning the membrane composition and permeability to osmolytes, the growing vesicles show recursive reproduction over several generations. Our "synthetic minimal cell" greatly simplifies the scheme of contemporary living cells while keeping their essence. The chemical pathways and the vesicle reproduction pathways are well described by kinetic equations and by applying the membrane elasticity model, respectively. This study provides new insights to better understand the differences and similarities between non-living forms of matter and life.
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Affiliation(s)
- Minoru Kurisu
- Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aramaki, Aoba, Sendai, 980-8578, Japan
| | - Ryosuke Katayama
- Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aramaki, Aoba, Sendai, 980-8578, Japan
| | - Yuka Sakuma
- Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aramaki, Aoba, Sendai, 980-8578, Japan
| | - Toshihiro Kawakatsu
- Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aramaki, Aoba, Sendai, 980-8578, Japan
| | - Peter Walde
- Department of Materials, ETH Zürich, Vladmir-Prelog-Weg 5, CH-8093, Zürich, Switzerland
| | - Masayuki Imai
- Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aramaki, Aoba, Sendai, 980-8578, Japan.
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25
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Disturbing the Spatial Organization of Biofilm Communities Affects Expression of agr-Regulated Virulence Factors in Staphylococcus aureus. Appl Environ Microbiol 2023; 89:e0193222. [PMID: 36700647 PMCID: PMC9973005 DOI: 10.1128/aem.01932-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Staphylococcus aureus uses quorum sensing and nutrient availability to control the expression of agr-regulated virulence factors. Quorum sensing is mediated by autoinducing peptide (AIP), which at a high concentration reduces expression of surface attachment proteins (coa, fnbpA) and increases expression of exotoxins (lukS) and proteases (splA). Nutrient availability can be sensed through the saeS/saeR system. Low nutrients increase expression of saeR, which augments expression of coa and fnbpA, distinct from the activity of AIP. The formation of spatial structure, such as biofilms, can alter quorum sensing and nutrient acquisition. In natural environments, biofilms encounter forces that may alter their spatial structure. These forces may impact quorum sensing and/or nutrient acquisition and thus affect the expression of agr-regulated virulence factors. However, this has not been studied. We show that periodically disturbing biofilms composed of S. aureus using a physical force affected the expression of agr-regulated virulence factors. In nutrient-poor environments, disturbance increased the expression of coa, fnbpA, lukS, and splA. Disturbance in a nutrient-rich environment at low or high disturbance amplitudes moderately reduced expression of coa and fnbpA but increased expression of lukS and splA. Interestingly, at an intermediate amplitude, the overall expression of agr-regulated virulence factors was the lowest; expression of lukS and splA remained unchanged relative to an undisturbed biofilm, while expression of coa and fnbpA significantly decreased. We hypothesize that these changes are a result of disturbance-driven changes in access to AIP and nutrients. Our results may allow the identification of environments where virulence is enhanced, or reduced, owing to a disturbance. IMPORTANCE Bacteria, such as Staphylococcus aureus, integrate signals from the environment to regulate genes encoding virulence factors. These signals include those produced by quorum-sensing systems and nutrient availability. We show that disturbing the spatial organization of S. aureus populations can lead to changes in the expression of virulence factors, likely by altering the ways in which S. aureus detects these signals. Our work may allow us to identify environments that increase or reduce the expression of virulence factors in S. aureus.
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26
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Han R, Feng XQ, Vollmer W, Stoodley P, Chen J. Deciphering the adaption of bacterial cell wall mechanical integrity and turgor to different chemical or mechanical environments. J Colloid Interface Sci 2023; 640:510-520. [PMID: 36878069 DOI: 10.1016/j.jcis.2023.02.100] [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: 12/28/2022] [Revised: 02/16/2023] [Accepted: 02/19/2023] [Indexed: 02/24/2023]
Abstract
Bacteria adapt the mechanical properties of their cell envelope, including cell wall stiffness, turgor, and cell wall tension and deformation, to grow and survive in harsh environments. However, it remains a technical challenge to simultaneously determine these mechanical properties at a single cell level. Here we combined theoretical modelling with an experimental approach to quantify the mechanical properties and turgor of Staphylococcus epidermidis. It was found that high osmolarity leads to a decrease in both cell wall stiffness and turgor. We also demonstrated that the turgor change is associated with a change in the viscosity of the bacterial cell. We predicted that the cell wall tension is much higher in deionized (DI) water and it decreases with an increase in osmolality. We also found that an external force increases the cell wall deformation to reinforce its adherence to a surface and this effect can be more significant in lower osmolarity. Overall, our work highlights how bacterial mechanics supports survival in harsh environments and uncovers the adaption of bacterial cell wall mechanical integrity and turgor to osmotic and mechanical challenges.
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Affiliation(s)
- Rui Han
- School of Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Xi-Qiao Feng
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Newcastle upon Tyne NE2 4AX, UK
| | - Paul Stoodley
- Department of Microbial Infection and Immunity and the Department of Orthopaedics, The Ohio State University, Columbus, OH 43210, United States; National Centre for Advanced Tribology at Southampton (nCATS), National Biofilm Innovation Centre (NBIC), Mechanical Engineering, University of Southampton, Southampton S017 1BJ, UK
| | - Jinju Chen
- School of Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK.
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27
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Abstract
Understanding the mechanism by which patterned gene activity leads to mechanical deformation of cells and tissues to create complex forms is a major challenge for developmental biology. Plants offer advantages for addressing this problem because their cells do not migrate or rearrange during morphogenesis, which simplifies analysis. We synthesize results from experimental analysis and computational modeling to show how mechanical interactions between cellulose fibers translate through wall, cell, and tissue levels to generate complex plant tissue shapes. Genes can modify mechanical properties and stresses at each level, though the values and pattern of stresses differ from one level to the next. The dynamic cellulose network provides elastic resistance to deformation while allowing growth through fiber sliding, which enables morphogenesis while maintaining mechanical strength.
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Affiliation(s)
- Enrico Coen
- Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Colney Lane, Norwich NR4 7UH, UK
| | - Daniel J Cosgrove
- Department of Biology, Pennsylvania State University, University Park, PA 16870, USA
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28
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Soil Chemistry and Soil History Significantly Structure Oomycete Communities in Brassicaceae Crop Rotations. Appl Environ Microbiol 2023; 89:e0131422. [PMID: 36629416 PMCID: PMC9888183 DOI: 10.1128/aem.01314-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Oomycetes are critically important in soil microbial communities, especially for agriculture, where they are responsible for major declines in yields. Unfortunately, oomycetes are vastly understudied compared to bacteria and fungi. As such, our understanding of how oomycete biodiversity and community structure vary through time in the soil remains poor. Soil history established by previous crops is one factor known to structure other soil microbes, but this has not been investigated for its influence on oomycetes. In this study, we established three different soil histories in field trials; the following year, these plots were planted with five different Brassicaceae crops. We hypothesized that the previously established soil histories would structure different oomycete communities, regardless of their current Brassicaceae crop host, in both the roots and rhizosphere. We used a nested internal transcribed spacer amplicon strategy incorporated with MiSeq metabarcoding, where the sequencing data was used to infer amplicon sequence variants of the oomycetes present in each sample. This allowed us to determine the impact of different soil histories on the structure and biodiversity of the oomycete root and rhizosphere communities from the five different Brassicaceae crops. We found that each soil history structured distinct oomycete rhizosphere communities, regardless of different Brassicaceae crop hosts, while soil chemistry structured the oomycete communities more during a dry year. Interestingly, soil history appeared specific to oomycetes but was less influential for bacterial communities previously identified from the same samples. These results advance our understanding of how different agricultural practices and inputs can alter edaphic factors to impact future oomycete communities. Examining how different soil histories endure and impact oomycete biodiversity will help clarify how these important communities may be assembled in agricultural soils. IMPORTANCE Oomycetes cause global plant diseases that result in substantial losses, yet they are highly understudied compared to other microbes, like fungi and bacteria. We wanted to investigate how past soil events, like changing crops in rotation, would impact subsequent oomycete communities. We planted different oilseed crops in three different soil histories and found that each soil history structured a distinct oomycete community regardless of which new oilseed crop was planted, e.g., oomycete communities from last year's lentil plots were still detected the following year regardless of which new oilseed crops we planted. This study demonstrated how different agricultural practices can impact future microbial communities differently. Our results also highlight the need for continued monitoring of oomycete biodiversity and quantification.
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29
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Chandler LM, Rodriguez M, Choe KP. RNAi screening for modulators of an osmo-sensitive gene response to extracellular matrix damage reveals negative feedback and interactions with translation inhibition. PLoS One 2023; 18:e0285328. [PMID: 37155688 PMCID: PMC10166495 DOI: 10.1371/journal.pone.0285328] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 04/19/2023] [Indexed: 05/10/2023] Open
Abstract
In epidermal tissues, extracellular matrices (ECMs) function as barriers between the organism and environment. Despite being at the interface with the environment, little is known about the role of animal barrier ECMs in sensing stress and communicating with cytoprotective gene pathways in neighboring cells. We and others have identified a putative damage sensor in the C. elegans cuticle that regulates osmotic, detoxification, and innate immune response genes. This pathway is associated with circumferential collagen bands called annular furrows; mutation or loss of furrow collagens causes constitutive activation of osmotic, detoxification, and innate immune response genes. Here, we performed a genome-wide RNAi screen for modulators of osmotic stress response gene gpdh-1 in a furrow collagen mutant strain. RNAi of six genes identified in this screen were tested under other conditions and for effects on other stress responses. The functions of these genes suggest negative feedback within osmolyte accumulation pathways and interactions with ATP homeostasis and protein synthesis. Loss of these gpdh-1 modulators had distinct effects on canonical detoxification and innate immune response genes.
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Affiliation(s)
- Luke M Chandler
- Department of Biology and Genetics Institute, University of Florida, Gainesville, FL, United States of America
| | - Michael Rodriguez
- Department of Biology and Genetics Institute, University of Florida, Gainesville, FL, United States of America
| | - Keith P Choe
- Department of Biology and Genetics Institute, University of Florida, Gainesville, FL, United States of America
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30
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Pérez-Guillén I, Domènech Ò, Botet-Carreras A, Merlos A, Sierra JM, Albericio F, de la Torre BG, Montero MT, Viñas M, Borrell JH. Studying Lipid Membrane Interactions of a Super-Cationic Peptide in Model Membranes and Living Bacteria. Pharmaceutics 2022; 14:pharmaceutics14102191. [PMID: 36297628 PMCID: PMC9611851 DOI: 10.3390/pharmaceutics14102191] [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: 09/09/2022] [Revised: 10/04/2022] [Accepted: 10/10/2022] [Indexed: 11/07/2022] Open
Abstract
The super-cationic peptide dendrimers (SCPD) family is a valuable class of antimicrobial peptide candidates for the future development of antibacterial agents against multidrug-resistant gram-negative bacteria. The deep knowledge of their mechanism of action is a major challenge in research, since it may be the basis for future modifications/optimizations. In this work we have explored the interaction between SCPD and membranes through biophysical and microbiological approaches in the case of the G1OLO-L2OL2 peptide. Results support the idea that the peptide is not only adsorbed or close to the surface of the membrane but associated/absorbed to some extent to the hydrophobic-hydrophilic region of the phospholipids. The presence of low concentrations of the peptide at the surface level is concomitant with destabilization of the cell integrity and this may contribute to osmotic stress, although other mechanisms of action cannot be ruled out.
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Affiliation(s)
- Isabel Pérez-Guillén
- Laboratory of Molecular Microbiology & Antimicrobials, Faculty of Medicine & Health Sciences, University of Barcelona, 08907 Barcelona, Spain
- Physical Chemistry Section, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
| | - Òscar Domènech
- Physical Chemistry Section, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
- Correspondence: (Ò.D.); (J.M.S.)
| | - Adrià Botet-Carreras
- Physical Chemistry Section, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
| | - Alexandra Merlos
- Laboratory of Molecular Microbiology & Antimicrobials, Faculty of Medicine & Health Sciences, University of Barcelona, 08907 Barcelona, Spain
| | - Josep M. Sierra
- Laboratory of Molecular Microbiology & Antimicrobials, Faculty of Medicine & Health Sciences, University of Barcelona, 08907 Barcelona, Spain
- Correspondence: (Ò.D.); (J.M.S.)
| | - Fernando Albericio
- Peptide Sciences Laboratory, School of Chemistry and Physics, University of KwaZulu-Natal, University Road, Westville, Durban 4001, South Africa
- CIBER-BBN, Networking Centre on Bioengineering, Biomaterials and Nanomedicine, Department of Organic Chemistry, University of Barcelona, 08028 Barcelona, Spain
| | - Beatriz G. de la Torre
- KRISP, College of Health Sciences, University of KwaZulu-Natal, Westville, Durban 4001, South Africa
| | - M. Teresa Montero
- Physical Chemistry Section, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
| | - Miguel Viñas
- Laboratory of Molecular Microbiology & Antimicrobials, Faculty of Medicine & Health Sciences, University of Barcelona, 08907 Barcelona, Spain
| | - Jordi H. Borrell
- Physical Chemistry Section, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
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31
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Han R, Vollmer W, Perry JD, Stoodley P, Chen J. Simultaneous determination of the mechanical properties and turgor of a single bacterial cell using atomic force microscopy. NANOSCALE 2022; 14:12060-12068. [PMID: 35946610 DOI: 10.1039/d2nr02577a] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Bacterial mechanical properties (cell wall stiffness and turgor) are important factors for bacterial survival in harsh environments. For an individual bacterial cell, it is challenging to determine the cell wall stiffness and turgor simultaneously. In this study, we adopted a combined finite element modelling and mathematical modelling approach to simultaneously determine bacterial cell wall stiffness and turgor of an individual bacterial cell based on atomic force microscopy (AFM) nanoindentation. The mechanical properties and turgor of Staphylococcus epidermidis, determined by our method are consistent with other independent studies. For a given aqueous environment, bacterial cell wall stiffness increased linearly with an increase in turgor. Higher osmolarity leads to a decrease in both cell wall stiffness and turgor. We also demonstrated that the change of turgor is associated with a change in viscosity of the bacterial cell.
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Affiliation(s)
- Rui Han
- School of Engineering, Newcastle University, Newcastle Upon Tyne, NE1 7RU, UK.
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Biosciences Institute, Newcastle University, Richardson Road, Newcastle upon Tyne, NE2 4AX, UK
| | - John D Perry
- Microbiology Department, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE7 7DN, UK
| | - Paul Stoodley
- Department of Microbial Infection and Immunity and the Department of Orthopaedics, The Ohio State University, Columbus, OH, 43210, USA
- National Centre for Advanced Tribology at Southampton (nCATS), National Biofilm Innovation Centre (NBIC), Mechanical Engineering, University of Southampton, Southampton, S017 1BJ, UK
| | - Jinju Chen
- School of Engineering, Newcastle University, Newcastle Upon Tyne, NE1 7RU, UK.
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32
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Blomberg A. Yeast osmoregulation - glycerol still in pole position. FEMS Yeast Res 2022; 22:6655991. [PMID: 35927716 PMCID: PMC9428294 DOI: 10.1093/femsyr/foac035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 06/29/2022] [Accepted: 08/02/2022] [Indexed: 11/14/2022] Open
Abstract
In response to osmotic dehydration cells sense, signal, alter gene expression, and metabolically counterbalance osmotic differences. The main compatible solute/osmolyte that accumulates in yeast cells is glycerol, which is produced from the glycolytic intermediate dihydroxyacetone phosphate. This review covers recent advancements in understanding mechanisms involved in sensing, signaling, cell-cycle delays, transcriptional responses as well as post-translational modifications on key proteins in osmoregulation. The protein kinase Hog1 is a key-player in many of these events, however, there is also a growing body of evidence for important Hog1-independent mechanisms playing vital roles. Several missing links in our understanding of osmoregulation will be discussed and future avenues for research proposed. The review highlights that this rather simple experimental system—salt/sorbitol and yeast—has developed into an enormously potent model system unravelling important fundamental aspects in biology.
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Affiliation(s)
- Anders Blomberg
- Dept. of Chemistry and Molecular Biology, University of Gothenburg, Sweden
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33
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Wray R, Wang J, Blount P, Iscla I. Activation of a Bacterial Mechanosensitive Channel, MscL, Underlies the Membrane Permeabilization of Dual-Targeting Antibacterial Compounds. Antibiotics (Basel) 2022; 11:antibiotics11070970. [PMID: 35884223 PMCID: PMC9312261 DOI: 10.3390/antibiotics11070970] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/13/2022] [Accepted: 07/15/2022] [Indexed: 01/27/2023] Open
Abstract
Resistance to antibiotics is a serious and worsening threat to human health worldwide, and there is an urgent need to develop new antibiotics that can avert it. One possible solution is the development of compounds that possess multiple modes of action, requiring at least two mutations to acquire resistance. Compound SCH-79797 both avoids resistance and has two mechanisms of action: one inhibiting the folate pathway, and a second described as “membrane permeabilization”; however, the mechanism by which membranes from bacterial cells, but not the host, are disrupted has remained mysterious. The opening of the bacterial mechanosensitive channel of large conductance, MscL, which ordinarily serves the physiological role of osmotic emergency release valves gated by hypoosmotic shock, has been previously demonstrated to affect bacterial membrane permeabilization. MscL allows the rapid permeabilization of both ions and solutes through the opening of the largest known gated pore, which has a diameter of 30 Å. We found that SCH-79797 and IRS-16, a more potent derivative, directly bind to the MscL channel and produce membrane permeabilization as a result of its activation. These findings suggest that possessing or adding an MscL-activating component to an antibiotic compound could help to lower toxicity and evade antibiotic resistance.
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Affiliation(s)
- Robin Wray
- Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA;
| | - Junmei Wang
- Computational Chemical Genomics Screening Center, Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburg, PA 15261, USA
- Correspondence: (J.W.); (P.B.); (I.I.)
| | - Paul Blount
- Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA;
- Correspondence: (J.W.); (P.B.); (I.I.)
| | - Irene Iscla
- Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA;
- Correspondence: (J.W.); (P.B.); (I.I.)
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34
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Imai M, Sakuma Y, Kurisu M, Walde P. From vesicles toward protocells and minimal cells. SOFT MATTER 2022; 18:4823-4849. [PMID: 35722879 DOI: 10.1039/d1sm01695d] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In contrast to ordinary condensed matter systems, "living systems" are unique. They are based on molecular compartments that reproduce themselves through (i) an uptake of ingredients and energy from the environment, and (ii) spatially and timely coordinated internal chemical transformations. These occur on the basis of instructions encoded in information molecules (DNAs). Life originated on Earth about 4 billion years ago as self-organised systems of inorganic compounds and organic molecules including macromolecules (e.g. nucleic acids and proteins) and low molar mass amphiphiles (lipids). Before the first living systems emerged from non-living forms of matter, functional molecules and dynamic molecular assemblies must have been formed as prebiotic soft matter systems. These hypothetical cell-like compartment systems often are called "protocells". Other systems that are considered as bridging units between non-living and living systems are called "minimal cells". They are synthetic, autonomous and sustainable reproducing compartment systems, but their constituents are not limited to prebiotic substances. In this review, we focus on both membrane-bounded (vesicular) protocells and minimal cells, and provide a membrane physics background which helps to understand how morphological transformations of vesicle systems might have happened and how vesicle reproduction might be coupled with metabolic reactions and information molecules. This research, which bridges matter and life, is a great challenge in which soft matter physics, systems chemistry, and synthetic biology must take joined efforts to better understand how the transformation of protocells into living systems might have occurred at the origin of life.
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Affiliation(s)
- Masayuki Imai
- Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aoba, Aramaki, Aoba, Sendai 980-8578, Japan.
| | - Yuka Sakuma
- Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aoba, Aramaki, Aoba, Sendai 980-8578, Japan.
| | - Minoru Kurisu
- Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aoba, Aramaki, Aoba, Sendai 980-8578, Japan.
| | - Peter Walde
- Department of Materials, ETH Zürich, Vladimir-Prelog-Weg 5, CH-8093 Zürich, Switzerland
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35
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Gaurivaud P, Tardy F. The Mycoplasma spp. ‘Releasome’: A New Concept for a Long-Known Phenomenon. Front Microbiol 2022; 13:853440. [PMID: 35495700 PMCID: PMC9051441 DOI: 10.3389/fmicb.2022.853440] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 03/14/2022] [Indexed: 11/13/2022] Open
Abstract
The bacterial secretome comprises polypeptides expressed at the cell surface or released into the extracellular environment as well as the corresponding secretion machineries. Despite their reduced coding capacities, Mycoplasma spp. are able to produce and release several components into their environment, including polypeptides, exopolysaccharides and extracellular vesicles. Technical difficulties in purifying these elements from the complex broth media used to grow mycoplasmas have recently been overcome by optimizing growth conditions and switching to chemically defined culture media. However, the secretion pathways responsible for the release of these structurally varied elements are still poorly described in mycoplasmas. We propose the use of the term ‘releasome,’ instead of secretome, to refer to molecules released by mycoplasmas into their environment. The aim of this review is to more precisely delineate the elements that should be considered part of the mycoplasmal releasome and their role in the interplay of mycoplasmas with host cells and tissues.
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Affiliation(s)
- Xu Han
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina, USA
| | - Christine K. Payne
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina, USA
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Mandela E, Stubenrauch CJ, Ryoo D, Hwang H, Cohen EJ, Torres VVL, Deo P, Webb CT, Huang C, Schittenhelm RB, Beeby M, Gumbart JC, Lithgow T, Hay ID. Adaptation of the periplasm to maintain spatial constraints essential for cell envelope processes and cell viability. eLife 2022; 11:73516. [PMID: 35084330 PMCID: PMC8824477 DOI: 10.7554/elife.73516] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 01/21/2022] [Indexed: 11/17/2022] Open
Abstract
The cell envelope of Gram-negative bacteria consists of two membranes surrounding a periplasm and peptidoglycan layer. Molecular machines spanning the cell envelope depend on spatial constraints and load-bearing forces across the cell envelope and surface. The mechanisms dictating spatial constraints across the cell envelope remain incompletely defined. In Escherichia coli, the coiled-coil lipoprotein Lpp contributes the only covalent linkage between the outer membrane and the underlying peptidoglycan layer. Using proteomics, molecular dynamics, and a synthetic lethal screen, we show that lengthening Lpp to the upper limit does not change the spatial constraint but is accommodated by other factors which thereby become essential for viability. Our findings demonstrate E. coli expressing elongated Lpp does not simply enlarge the periplasm in response, but the bacteria accommodate by a combination of tilting Lpp and reducing the amount of the covalent bridge. By genetic screening, we identified all of the genes in E. coli that become essential in order to enact this adaptation, and by quantitative proteomics discovered that very few proteins need to be up- or down-regulated in steady-state levels in order to accommodate the longer Lpp. We observed increased levels of factors determining cell stiffness, a decrease in membrane integrity, an increased membrane vesiculation and a dependance on otherwise non-essential tethers to maintain lipid transport and peptidoglycan biosynthesis. Further this has implications for understanding how spatial constraint across the envelope controls processes such as flagellum-driven motility, cellular signaling, and protein translocation
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Affiliation(s)
- Eric Mandela
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | | | - David Ryoo
- Interdisciplinary Bioengineering Graduate Program, Georgia Institute of Technology, Atlanta, United States
| | - Hyea Hwang
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States
| | - Eli J Cohen
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | | | - Pankaj Deo
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Chaille T Webb
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Cheng Huang
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | - Ralf B Schittenhelm
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | - Morgan Beeby
- Department of Life Sciencesa, Imperial College London, London, United Kingdom
| | - James C Gumbart
- School of Physics, Georgia Institute of Technology, Atlanta, United States
| | - Trevor Lithgow
- Department of Microbiology, Monash University, Melbourne, Australia
| | - Iain D Hay
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand
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38
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Malik AA, Bouskill NJ. Drought impacts on microbial trait distribution and feedback to soil carbon cycling. Funct Ecol 2022. [DOI: 10.1111/1365-2435.14010] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Ashish A. Malik
- School of Biological Sciences University of Aberdeen Aberdeen UK
| | - Nicholas J. Bouskill
- Climate and Ecosystem Sciences Division Lawrence Berkeley National Laboratory Berkeley California USA
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39
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On the osmotic pressure of cells. QRB DISCOVERY 2022. [PMID: 37529285 PMCID: PMC10392628 DOI: 10.1017/qrd.2022.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Abstract
The chemical potential of water (
$ {\mu}_{{\mathrm{H}}_2\mathrm{O}} $
) provides an essential thermodynamic characterization of the environment of living organisms, and it is of equal significance as the temperature. For cells,
$ {\mu}_{{\mathrm{H}}_2\mathrm{O}} $
is conventionally expressed in terms of the osmotic pressure (πosm). We have previously suggested that the main contribution to the intracellular πosm of the bacterium E. coli is from soluble negatively-charged proteins and their counter-ions. Here, we expand on this analysis by examining how evolutionary divergent cell types cope with the challenge of maintaining πosm within viable values. Complex organisms, like mammals, maintain constant internal πosm ≈ 0.285 osmol, matching that of 0.154 M NaCl. For bacteria it appears that optimal growth conditions are found for similar or slightly higher πosm (0.25-0.4 osmol), despite that they represent a much earlier stage in evolution. We argue that this value reflects a general adaptation for optimising metabolic function under crowded intracellular conditions. Environmental πosm that differ from this optimum require therefore special measures, as exemplified with gram-positive and gram-negative bacteria. To handle such situations, their membrane encapsulations allow for a compensating turgor pressure that can take both positive and negative values, where positive pressures allow increased frequency of metabolic events through increased intracellular protein concentrations. A remarkable exception to the rule of 0.25-0.4 osmol, is found for halophilic archaea with internal πosm ≈ 15 osmol. The internal organization of these archaea differs in that they utilize a repulsive electrostatic mechanism operating only in the ionic-liquid regime to avoid aggregation, and that they stand out from other organisms by having no turgor pressure.
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Cell Envelope Stress Response in Pseudomonas aeruginosa. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1386:147-184. [DOI: 10.1007/978-3-031-08491-1_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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41
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Eco-friendly bacteria-killing by nanorods through mechano-puncture with top selectivity. Bioact Mater 2021; 15:173-184. [PMID: 35386355 PMCID: PMC8941167 DOI: 10.1016/j.bioactmat.2021.11.028] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/25/2021] [Accepted: 11/25/2021] [Indexed: 11/20/2022] Open
Abstract
Nanorods can induce mechano-puncture of Staphylococcus aureus (S. aureus) that often impairs osseointegration of orthopedic implants, while the critical nanorod top sharpness able to puncture S. aureus and the predominant contributor between top sharpness and length to mechano-puncture activity remains elusive. Herein, we fabricated three kinds of Al2O3-wrapped nanorods patterned arrays with different lengths and top sharpness. The top-sharp nanorods have lengths of 469 and 884 nm and the shorter show a length identical to the top-flat nanorods. Driven by the equivalent adhesive force of S. aureus, the top-flat nanorods deform cell envelops, showing a bacteriostatic rate of 29% owing to proliferation-inhibited manner. The top-sharp nanorods puncture S. aureus, showing a bactericidal rate of 96% for the longer, and 98% for the shorter that simultaneously exhibits fair osseointegration in bacteria-infected rat tibias, identifying top sharpness as a predominate contributor to mechano-puncture activity. Based on finite-element simulation, such top-flat nanorod derives the maximum stress (Smax) of 5.65 MPa on cell wall, lower than its ultimate-tensile-strength (13 MPa); while such top-sharp and shorter nanorod derives Smax of 20.15 MPa to puncture cell envelop. Moreover, a critical top conical angle of 138° is identified for nanorods able to puncture S. aureus. Top sharpness depended mechano-puncture of nanorods against S. aureus is clarified. Top-flat nanorods deform bacterial cell envelop to inhibit their proliferation. Top-sharp nanorods (conical angle of 50°) puncture bacteria to intensely kill them. 138° is confirmed as critical top conical angle for nanorods to puncture S. aureus.
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Dike KS, Okafor CP, Ohabughiro BN, Maduwuba MC, Ezeokoli OT, Ayeni KI, Okafor CM, Ezekiel CN. Analysis of bacterial communities of three cassava-based traditionally fermented Nigerian foods (abacha, fufu and garri). Lett Appl Microbiol 2021; 74:452-461. [PMID: 34850410 DOI: 10.1111/lam.13621] [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: 08/30/2021] [Revised: 10/27/2021] [Accepted: 11/13/2021] [Indexed: 11/26/2022]
Abstract
Globally, cassava is an important food crop that contributes significantly to food security. In Nigeria, cassava can be traditionally processed into abacha (fermented strips), fufu (submerged-fermented porridge) and garri (solid-state fermented farinated granules) for human consumption. Despite the widespread consumption of these foods, there is a major knowledge gap in understanding their core bacterial diversity. This study, therefore, applied next-generation sequencing of 16S rRNA gene to delineate the bacterial diversity in abacha, fufu and garri. Amplicon sequence variants belonging to nine phyla were present in the three foods. Firmicutes dominated the bacterial community of abacha and fufu, whereas, Proteobacteria was the dominant phylum in garri. At genus level taxa, Lactococcus, Lysinibacillus and Pseudomonas dominated the bacterial community in abacha, fufu and garri, respectively. Other dominant phylotypes reported in the foods belonged to Bacillus, Clostridium sensu stricto (cluster 1), Cupriavidus, Enterobacter, Sphingomonas and Staphylococcus. To the best of our knowledge, Clostridium sensu stricto cluster 1 and Lysinibacillus in fufu, and Brevundimonas, Cupriavidus, Sphingomonas and Strenotrophomomas in garri are reported for the first time. Although some potential pathogenic genera were recorded, the foods contained potentially functional species that could be explored to improve artisanal food production, food security and safeguard consumer health.
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Affiliation(s)
- K S Dike
- Department of Microbiology, Imo State University, Owerri, Nigeria
| | - C P Okafor
- Department of Microbiology, Imo State University, Owerri, Nigeria
| | - B N Ohabughiro
- Department of Microbiology, Imo State University, Owerri, Nigeria
| | - M C Maduwuba
- Department of Microbiology, Imo State University, Owerri, Nigeria
| | - O T Ezeokoli
- Department of Microbiology and Biochemistry, University of the Free State, Bloemfontein, South Africa
| | - K I Ayeni
- Department of Microbiology, Babcock University, Ilishan Remo, Nigeria
| | - C M Okafor
- Department of Applied Microbiology and Brewing, Nnamdi Azikiwe University, Awka, Nigeria
| | - C N Ezekiel
- Department of Microbiology, Babcock University, Ilishan Remo, Nigeria
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Geng X, Khalil CA, Prince RC, Lee K, An C, Boufadel MC. Hypersaline Pore Water in Gulf of Mexico Beaches Prevented Efficient Biodegradation of Deepwater Horizon Beached Oil. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:13792-13801. [PMID: 34617733 DOI: 10.1021/acs.est.1c02760] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The 2010 Deepwater Horizon (DWH) blowout released 3.19 million barrels (435 000 tons) of crude oil into the Gulf of Mexico. Driven by currents and wind, an estimated 22 000 tons of spilled oil were deposited onto the northeastern Gulf shorelines, adversely impacting the ecosystems and economies of the Gulf coast regions. In this work we present field work conducted at the Gulf beaches in three U.S. States during 2010-2011: Louisiana, Alabama, and Florida, to explore endogenous mechanisms that control persistence and biodegradation of the MC252-oil deposited within beach sediments as deep as 50 cm. The work involved over 1500 measurements incorporating oil chemistry, hydrocarbon-degrading microbial populations, nutrient and DO concentrations, and intrinsic beach properties. We found that intrinsic beach capillarity along with groundwater depth provides primary controls on aeration and infiltration of near-surface sediments, thereby modulating moisture and redox conditions within the oil-contaminated zone. In addition, atmosphere-ocean-groundwater interactions created hypersaline sediment environments near the beach surface at all the studied sites. The fact that the oil-contaminated sediments retained near or above 20% moisture content and were also eutrophic and aerobic suggests that the limiting factor for oil biodegradation is the hypersaline environment due to evaporation, a fact not reported in prior studies. These results highlight the importance of beach porewater hydrodynamics in generating unique hypersaline sediment environments that inhibited oil decomposition along the Gulf shorelines following DWH.
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Affiliation(s)
- Xiaolong Geng
- Department of Civil and Environmental Engineering, New Jersey Institute of Technology, University Heights, Newark, New Jersey 07102, United States
| | - Charbel Abou Khalil
- Department of Civil and Environmental Engineering, New Jersey Institute of Technology, University Heights, Newark, New Jersey 07102, United States
| | - Roger C Prince
- Stonybrook Apiary, Pittstown, New Jersey, 08867, United States
| | - Kenneth Lee
- Department of Fisheries and Oceans, Dartmouth, Nova Scotia B2Y 4A2, Canada
| | - Chunjiang An
- Department of Building, Civil and Environmental Engineering, Concordia University, Montreal, Quebec H3G 2W1, Canada
| | - Michel C Boufadel
- Department of Civil and Environmental Engineering, New Jersey Institute of Technology, University Heights, Newark, New Jersey 07102, United States
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Marconi M, Wabnik K. Shaping the Organ: A Biologist Guide to Quantitative Models of Plant Morphogenesis. FRONTIERS IN PLANT SCIENCE 2021; 12:746183. [PMID: 34675952 PMCID: PMC8523991 DOI: 10.3389/fpls.2021.746183] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 09/09/2021] [Indexed: 06/13/2023]
Abstract
Organ morphogenesis is the process of shape acquisition initiated with a small reservoir of undifferentiated cells. In plants, morphogenesis is a complex endeavor that comprises a large number of interacting elements, including mechanical stimuli, biochemical signaling, and genetic prerequisites. Because of the large body of data being produced by modern laboratories, solving this complexity requires the application of computational techniques and analyses. In the last two decades, computational models combined with wet-lab experiments have advanced our understanding of plant organ morphogenesis. Here, we provide a comprehensive review of the most important achievements in the field of computational plant morphodynamics. We present a brief history from the earliest attempts to describe plant forms using algorithmic pattern generation to the evolution of quantitative cell-based models fueled by increasing computational power. We then provide an overview of the most common types of "digital plant" paradigms, and demonstrate how models benefit from diverse techniques used to describe cell growth mechanics. Finally, we highlight the development of computational frameworks designed to resolve organ shape complexity through integration of mechanical, biochemical, and genetic cues into a quantitative standardized and user-friendly environment.
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Affiliation(s)
| | - Krzysztof Wabnik
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Pozuelo de Alarcón (Madrid), Spain
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45
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46
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Sun J, Shi H, Huang KC. Hyperosmotic Shock Transiently Accelerates Constriction Rate in Escherichia coli. Front Microbiol 2021; 12:718600. [PMID: 34489908 PMCID: PMC8418109 DOI: 10.3389/fmicb.2021.718600] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 07/26/2021] [Indexed: 11/13/2022] Open
Abstract
Bacterial cells in their natural environments encounter rapid and large changes in external osmolality. For instance, enteric bacteria such as Escherichia coli experience a rapid decrease when they exit from host intestines. Changes in osmolality alter the mechanical load on the cell envelope, and previous studies have shown that large osmotic shocks can slow down bacterial growth and impact cytoplasmic diffusion. However, it remains unclear how cells maintain envelope integrity and regulate envelope synthesis in response to osmotic shocks. In this study, we developed an agarose pad-based protocol to assay envelope stiffness by measuring population-averaged cell length before and after a hyperosmotic shock. Pad-based measurements exhibited an apparently larger length change compared with single-cell dynamics in a microfluidic device, which we found was quantitatively explained by a transient increase in division rate after the shock. Inhibiting cell division led to consistent measurements between agarose pad-based and microfluidic measurements. Directly after hyperosmotic shock, FtsZ concentration and Z-ring intensity increased, and the rate of septum constriction increased. These findings establish an agarose pad-based protocol for quantifying cell envelope stiffness, and demonstrate that mechanical perturbations can have profound effects on bacterial physiology.
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Affiliation(s)
- Jiawei Sun
- Department of Bioengineering, Stanford University, Stanford, CA, United States
| | - Handuo Shi
- Department of Bioengineering, Stanford University, Stanford, CA, United States.,Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, United States
| | - Kerwyn Casey Huang
- Department of Bioengineering, Stanford University, Stanford, CA, United States.,Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, United States.,Chan Zuckerberg Biohub, San Francisco, CA, United States
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47
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Sommer A, Fuchs S, Layer F, Schaudinn C, Weber RE, Richard H, Erdmann MB, Laue M, Schuster CF, Werner G, Strommenger B. Mutations in the gdpP gene are a clinically relevant mechanism for β-lactam resistance in meticillin-resistant Staphylococcus aureus lacking mec determinants. Microb Genom 2021; 7. [PMID: 34486969 PMCID: PMC8715439 DOI: 10.1099/mgen.0.000623] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In Staphylococcus aureus, resistance to β-lactamase stable β-lactam antibiotics is mediated by the penicillinbinding protein 2a, encoded by mecA or by its homologues mecB or mecC. However, a substantial number of meticillin-resistant isolates lack known mec genes and, thus, are called meticillin resistant lacking mec (MRLM). This study aims to identify the genetic mechanisms underlying the MRLM phenotype. A total of 141 MRLM isolates and 142 meticillin-susceptible controls were included in this study. Oxacillin and cefoxitin minimum inhibitory concentrations were determined by broth microdilution and the presence of mec genes was excluded by PCR. Comparative genomics and a genome-wide association study (GWAS) approach were applied to identify genetic polymorphisms associated with the MRLM phenotype. The potential impact of such mutations on the expression of PBP4, as well as on cell morphology and biofilm formation, was investigated. GWAS revealed that mutations in gdpP were significantly associated with the MRLM phenotype. GdpP is a phosphodiesterase enzyme involved in the degradation of the second messenger cyclic-di-AMP in S. aureus. A total of 131 MRLM isolates carried truncations, insertions or deletions as well as amino acid substitutions, mainly located in the functional DHH-domain of GdpP. We experimentally verified the contribution of these gdpP mutations to the MRLM phenotype by heterologous complementation experiments. The mutations in gdpP had no effect on transcription levels of pbp4; however, cell sizes of MRLM strains were reduced. The impact on biofilm formation was highly strain dependent. We report mutations in gdpP as a clinically relevant mechanism for β-lactam resistance in MRLM isolates. This observation is of particular clinical relevance, since MRLM are easily misclassified as MSSA (meticillin-susceptible S. aureus), which may lead to unnoticed spread of β-lactam-resistant isolates and subsequent treatment failure.
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Affiliation(s)
- Anna Sommer
- Department of Infectious Diseases, Nosocomial Pathogens and Antibiotic Resistances, Robert Koch Institute, Wernigerode, Germany
| | - Stephan Fuchs
- Methodology and Research Infrastructure, Bioinformatics, Robert Koch Institute, Berlin, Germany
| | - Franziska Layer
- Department of Infectious Diseases, Nosocomial Pathogens and Antibiotic Resistances, Robert Koch Institute, Wernigerode, Germany
| | - Christoph Schaudinn
- Centre for Biological Threats and Special Pathogens, Advanced Light and Electron Microscopy, Robert Koch Institute, Berlin, Germany
| | - Robert E Weber
- Department of Infectious Diseases, Nosocomial Pathogens and Antibiotic Resistances, Robert Koch Institute, Wernigerode, Germany
| | - Hugues Richard
- Methodology and Research Infrastructure, Bioinformatics, Robert Koch Institute, Berlin, Germany
| | - Mareike B Erdmann
- Department of Infectious Diseases, Nosocomial Pathogens and Antibiotic Resistances, Robert Koch Institute, Wernigerode, Germany
| | - Michael Laue
- Centre for Biological Threats and Special Pathogens, Advanced Light and Electron Microscopy, Robert Koch Institute, Berlin, Germany
| | - Christopher F Schuster
- Department of Infectious Diseases, Nosocomial Pathogens and Antibiotic Resistances, Robert Koch Institute, Wernigerode, Germany
| | - Guido Werner
- Department of Infectious Diseases, Nosocomial Pathogens and Antibiotic Resistances, Robert Koch Institute, Wernigerode, Germany
| | - Birgit Strommenger
- Department of Infectious Diseases, Nosocomial Pathogens and Antibiotic Resistances, Robert Koch Institute, Wernigerode, Germany
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Robust surface-to-mass coupling and turgor-dependent cell width determine bacterial dry-mass density. Proc Natl Acad Sci U S A 2021; 118:2021416118. [PMID: 34341116 PMCID: PMC8364103 DOI: 10.1073/pnas.2021416118] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Intracellular biomass density is an important variable for cellular physiology. It defines the crowded state of the cytoplasm and thus influences macromolecular interactions and transport. To control density during growth, bacteria must expand their cell volumes in synchrony with biomass. The regulation of volume growth and biomass density remain fundamentally not understood—in bacteria or any other organism. Using advanced microscopy, we demonstrate that cells control dry-mass density indirectly through two independent processes. First, cells expand surface area, rather than volume, in proportion with biomass growth. Second, cell width is controlled independently, with an important influence of turgor pressure. Our findings overturn a long-standing paradigm of mass-density constancy in bacteria and reveal fundamental determinants of dry-mass density and shape. During growth, cells must expand their cell volumes in coordination with biomass to control the level of cytoplasmic macromolecular crowding. Dry-mass density, the average ratio of dry mass to volume, is roughly constant between different nutrient conditions in bacteria, but it remains unknown whether cells maintain dry-mass density constant at the single-cell level and during nonsteady conditions. Furthermore, the regulation of dry-mass density is fundamentally not understood in any organism. Using quantitative phase microscopy and an advanced image-analysis pipeline, we measured absolute single-cell mass and shape of the model organisms Escherichia coli and Caulobacter crescentus with improved precision and accuracy. We found that cells control dry-mass density indirectly by expanding their surface, rather than volume, in direct proportion to biomass growth—according to an empirical surface growth law. At the same time, cell width is controlled independently. Therefore, cellular dry-mass density varies systematically with cell shape, both during the cell cycle or after nutrient shifts, while the surface-to-mass ratio remains nearly constant on the generation time scale. Transient deviations from constancy during nutrient shifts can be reconciled with turgor-pressure variations and the resulting elastic changes in surface area. Finally, we find that plastic changes of cell width after nutrient shifts are likely driven by turgor variations, demonstrating an important regulatory role of mechanical forces for width regulation. In conclusion, turgor-dependent cell width and a slowly varying surface-to-mass coupling constant are the independent variables that determine dry-mass density.
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Guyot S, Pottier L, Bertheau L, Dumont J, Dorelle Hondjuila Miokono E, Dupont S, Ragon M, Denimal E, Marin A, Hallsworth JE, Beney L, Gervais P. Increased xerotolerance of Saccharomyces cerevisiae during an osmotic pressure ramp over several generations. Microb Biotechnol 2021; 14:1445-1461. [PMID: 33739621 PMCID: PMC8313259 DOI: 10.1111/1751-7915.13789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 02/12/2021] [Accepted: 02/17/2021] [Indexed: 12/01/2022] Open
Abstract
Although mechanisms involved in response of Saccharomyces cerevisiae to osmotic challenge are well described for low and sudden stresses, little is known about how cells respond to a gradual increase of the osmotic pressure (reduced water activity; aw ) over several generations as it could encounter during drying in nature or in food processes. Using glycerol as a stressor, we propagated S. cerevisiae through a ramp of the osmotic pressure (up to high molar concentrations to achieve testing-to-destruction) at the rate of 1.5 MPa day-1 from 1.38 to 58.5 MPa (0.990-0.635 aw ). Cultivability (measured at 1.38 MPa and at the harvest osmotic pressure) and glucose consumption compared with the corresponding sudden stress showed that yeasts were able to grow until about 10.5 MPa (0.926 aw ) and to survive until about 58.5 MPa, whereas glucose consumption occurred until 13.5 MPa (about 0.915 aw ). Nevertheless, the ramp conferred an advantage since yeasts harvested at 10.5 and 34.5 MPa (0.778 aw ) showed a greater cultivability than glycerol-shocked cells after a subsequent shock at 200 MPa (0.234 aw ) for 2 days. FTIR analysis revealed structural changes in wall and proteins in the range 1.38-10.5 MPa, which would be likely to be involved in the resistance at extreme osmotic pressure.
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Affiliation(s)
- Stéphane Guyot
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, F-21000, France
| | - Laurence Pottier
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, F-21000, France
| | - Lucie Bertheau
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, F-21000, France
| | - Jennifer Dumont
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, F-21000, France
| | | | - Sébastien Dupont
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, F-21000, France
| | - Mélanie Ragon
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, F-21000, France
| | - Emmanuel Denimal
- Direction des Systèmes d'Information, AgroSup Dijon, 26 Boulevard Docteur Petitjean, Dijon, 21000, France
| | - Ambroise Marin
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, F-21000, France
| | - John E Hallsworth
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL, UK
| | - Laurent Beney
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, F-21000, France
| | - Patrick Gervais
- Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Dijon, F-21000, France
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Cui Q, Liu T, Li X, Zhao L, Wu Q, Wang X, Song K, Ge D. Validation of the mechano-bactericidal mechanism of nanostructured surfaces with finite element simulation. Colloids Surf B Biointerfaces 2021; 206:111929. [PMID: 34147928 DOI: 10.1016/j.colsurfb.2021.111929] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 06/02/2021] [Accepted: 06/14/2021] [Indexed: 10/21/2022]
Abstract
The mechano-bactericidal property of nanostructured surfaces has become the focus of intensive research toward the development of a new generation of antibacterial surfaces, especially in the current era of spreading antibiotic resistance. However, the mechanisms underlying nanostructured surfaces mechanically damaging bacteria remain unclear, which ultimately limits translational potential toward real-world applications. Using finite element simulation technique, we developed the three-dimensional thin wall with turgor pressure finite element model (3D-TWTP-FEM) of bacterial cell and verified the reliability of this model by the AFM indentation experiment simulation of the cell, and the cell model is able to simulate suspended bacterial cell and the process of cell adhering to the flat and nanopillar surfaces. Since bacterial cells suffer greater stress and deformation on the nanopillar surfaces, a two-stage model of the elastic and creep deformation stage of the cells on the nanostructured surfaces was developed. The calculations show that the location of the maximum stress/strain on the cells adhered to the nanopillar surfaces is at the liquid-cell-nanopillar three phase contact line. The computational results confirmed the ability of nanostructured surfaces to mechanically lyse bacteria and gave the effect of nanopillar geometry on the efficiency and speed of bacterial cell rupture. This study provides fundamental physical insights into how nanopillar surfaces can serve as effective and fast mechanical antimicrobial materials.
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Affiliation(s)
- Qianqian Cui
- School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, Liaoning Province, PR China
| | - Tianqing Liu
- School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, Liaoning Province, PR China.
| | - Xiangqin Li
- School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, Liaoning Province, PR China
| | - Lidan Zhao
- School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, Liaoning Province, PR China
| | - Qiqi Wu
- School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, Liaoning Province, PR China
| | - Xin Wang
- School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, Liaoning Province, PR China
| | - Kedong Song
- School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, Liaoning Province, PR China
| | - Dan Ge
- School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, Liaoning Province, PR China
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