1
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Akkiraju AG, Atcha KR, Sagurthi SR. Cloning, Purification, and Biophysical Characterization of FemB Protein from Methicillin-Resistant Staphylococcus aureus and Inhibitors Screening. Appl Biochem Biotechnol 2023:10.1007/s12010-023-04780-8. [PMID: 37991634 DOI: 10.1007/s12010-023-04780-8] [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] [Accepted: 10/31/2023] [Indexed: 11/23/2023]
Abstract
Methicillin-resistant Staphylococcus aureus has emerged as a leading cause of nosocomial, community acquired infections worldwide. Earlier investigations revealed that mecA-encoded FEM proteins play a role in antimicrobial resistance by developing unique peptidoglycan cross-linking which helps in the formation of protective cell membrane. In view to this, present study focused on expression, purification FEM proteins, and FemB biophysical characterization with the aid of in silico and in vitro approaches. Furthermore, we carried out biological screening assays and identified the novel potent 1,2,3-triazole conjugated 1,3,4-oxadiazole hybrid molecule which could inhibit the MRSA than the proven oxacillin.
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Affiliation(s)
- Anjini Gayatri Akkiraju
- Molecular Medicine Lab, Dept. of Genetics & Biotechnology, Osmania University, Hyderabad, Telangana, 500007, India
| | - Krishnam Raju Atcha
- Department of Chemistry, Nizam College, Osmania University, Hyderabad, Telangana, 500001, India
| | - Someswar Rao Sagurthi
- Molecular Medicine Lab, Dept. of Genetics & Biotechnology, Osmania University, Hyderabad, Telangana, 500007, India.
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2
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Kim U, Lee SY, Oh SW. A review of mechanism analysis methods in multi-species biofilm of foodborne pathogens. Food Sci Biotechnol 2023; 32:1665-1677. [PMID: 37780597 PMCID: PMC10533759 DOI: 10.1007/s10068-023-01317-x] [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: 01/17/2023] [Revised: 04/13/2023] [Accepted: 04/17/2023] [Indexed: 10/03/2023] Open
Abstract
Biofilms are an aggregation of microorganisms that have high resistance to antimicrobial agents. In the food industry, it has been widely studied that foodborne pathogens on both food surfaces and food-contact surfaces can form biofilms thereby threatening the safety of the food. In the natural environment, multi-species biofilms formed by more than two different microorganisms are abundant. In addition, the resistance of multi-species biofilms to antimicrobial agents is higher than that of mono-species biofilms. Therefore, studies to elucidate the mechanisms of multi-species biofilms formed by foodborne pathogens are still required in the food industry. In this review paper, we summarized the novel analytical methods studied to evaluate the mechanisms of multi-species biofilms formed by foodborne pathogens by dividing them into four categories: spatial distribution, bacterial interaction, extracellular polymeric substance production and quorum sensing analytical methods.
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Affiliation(s)
- Unji Kim
- Department of Food and Nutrition, Kookmin University, Seoul, 02727 Republic of Korea
| | - So-Young Lee
- Department of Food and Nutrition, Kookmin University, Seoul, 02727 Republic of Korea
| | - Se-Wook Oh
- Department of Food and Nutrition, Kookmin University, Seoul, 02727 Republic of Korea
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3
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Wójtowicz D, Stodolak-Zych E. Strategies to Mitigate Biofouling of Nanocomposite Polymer-Based Membranes in Contact with Blood. MEMBRANES 2023; 13:762. [PMID: 37755184 PMCID: PMC10536434 DOI: 10.3390/membranes13090762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/21/2023] [Accepted: 08/25/2023] [Indexed: 09/28/2023]
Abstract
An extracorporeal blood purification method called continuous renal replacement therapy uses a porous hollow-fiber polymeric membrane that is exposed to prolonged contact with blood. In that condition, like with any other submerged filtration membrane, the hemofilter loses its properties over time and use resulting in a rapid decline in flux. The most significant reason for this loss is the formation of a biofilm. Protein, blood cells and bacterial cells attach to the membrane surface in complex and fluctuating processes. Anticoagulation allows for longer patency of vascular access and a longer lifespan of the membrane. Other preventive measures include the modification of the membrane itself. In this article, we focused on the role of nanoadditives in the mitigation of biofouling. Nanoparticles such as graphene, carbon nanotubes, and silica effectively change surface properties towards more hydrophilic, affect pore size and distribution, decrease protein adsorption and damage bacteria cells. As a result, membranes modified with nanoparticles show better flow parameters, longer lifespan and increased hemocompatibility.
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Affiliation(s)
- Dominika Wójtowicz
- Department of Biomaterials and Composites, Faculty of Materials Science and Ceramics, AGH University of Krakow, Al. Mickiewicza 30, 30-059 Krakow, Poland;
- Clinical Department of Anaesthesiology and Intensive Care, University Hospital in Krakow, ul. Jakubowskiego 2, 30-688 Krakow, Poland
| | - Ewa Stodolak-Zych
- Department of Biomaterials and Composites, Faculty of Materials Science and Ceramics, AGH University of Krakow, Al. Mickiewicza 30, 30-059 Krakow, Poland;
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4
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Yuan L, Straub H, Shishaeva L, Ren Q. Microfluidics for Biofilm Studies. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2023; 16:139-159. [PMID: 37314876 DOI: 10.1146/annurev-anchem-091522-103827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Biofilms are multicellular communities held together by a self-produced extracellular matrix and exhibit a set of properties that distinguish them from free-living bacteria. Biofilms are exposed to a variety of mechanical and chemical cues resulting from fluid motion and mass transport. Microfluidics provides the precise control of hydrodynamic and physicochemical microenvironments to study biofilms in general. In this review, we summarize the recent progress made in microfluidics-based biofilm research, including understanding the mechanism of bacterial adhesion and biofilm development, assessment of antifouling and antimicrobial properties, development of advanced in vitro infection models, and advancement in methods to characterize biofilms. Finally, we provide a perspective on the future direction of microfluidics-assisted biofilm research.
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Affiliation(s)
- Lu Yuan
- Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, China;
| | - Hervé Straub
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland;
| | - Liubov Shishaeva
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland;
| | - Qun Ren
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland;
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5
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Burmeister N, Vollstedt C, Kröger C, Friedrich T, Scharnagl N, Rohnke M, Zorn E, Wicha SG, Streit WR, Maison W. Zwitterionic surface modification of polyethylene via atmospheric plasma-induced polymerization of (vinylbenzyl-)sulfobetaine and evaluation of antifouling properties. Colloids Surf B Biointerfaces 2023; 224:113195. [PMID: 36758459 DOI: 10.1016/j.colsurfb.2023.113195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/31/2023] [Accepted: 02/02/2023] [Indexed: 02/05/2023]
Abstract
Zwitterionic polymer brushes were grafted from bulk polyethylene (PE) by air plasma activation of the PE surface followed by radical polymerization of the zwitterionic styrene derivative (vinylbenzyl)sulfobetaine (VBSB). Successful formation of dense poly-(VBSB)-brush layers was confirmed by goniometry, IR spectroscopy, XPS and ToF-SIMS analysis. The resulting zwitterionic layers are about 50-100 nm thick and cause extremely low contact angles of 10° (water) on the material. Correspondingly we determined a high density of > 1.0 × 1016 solvent accessible zwitterions/cm2 (corresponding to 2,0 *10-8 mol/cm2) by a UV-based ion-exchange assay with crystal violet. The elemental composition as determined by XPS and characteristic absorption bands in the IR spectra confirmed the presence of zwitterionic sulfobetaine polymer brushes. The antifouling properties of the resulting materials were evaluated in a bacterial adhesion test against gram-positive bacteria (S. aureus). We observed significantly reduced cellular adhesion of the zwitterionic material compared to pristine PE. These microbiological tests were complemented by tests in natural seawater. During a test period of 21 days, confocal microscopy revealed excellent antifouling properties and confirmed the operating antifouling mechanism. The procedure reported herein allows the efficient surface modification of bulk PE with zwitterionic sulfobetaine polymer brushes via a scalable approach. The resulting modified PE retains important properties of the bulk material and has excellent and durable antifouling properties.
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Affiliation(s)
- Nils Burmeister
- Universität Hamburg, Department of Chemistry, Bundesstrasse 45, 20146 Hamburg, Germany
| | - Christel Vollstedt
- Universität Hamburg, Department of Microbiology and Biotechnology, Ohnhorststrasse 18, 22609 Hamburg, Germany
| | - Cathrin Kröger
- Universität Hamburg, Department of Microbiology and Biotechnology, Ohnhorststrasse 18, 22609 Hamburg, Germany
| | - Timo Friedrich
- Universität Hamburg, Department of Chemistry, Bundesstrasse 45, 20146 Hamburg, Germany
| | - Nico Scharnagl
- Helmholtz-Zentrum Hereon GmbH, Institute of Surface Science, Max-Planck-Strasse 1, 21502 Geesthacht, Germany
| | - Marcus Rohnke
- Justus-Liebig-Universität Gießen, Institute of Physical Chemistry, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
| | - Eilika Zorn
- Universität Hamburg, Department of Chemistry, Bundesstrasse 45, 20146 Hamburg, Germany
| | - Sebastian G Wicha
- Universität Hamburg, Department of Chemistry, Bundesstrasse 45, 20146 Hamburg, Germany
| | - Wolfgang R Streit
- Universität Hamburg, Department of Microbiology and Biotechnology, Ohnhorststrasse 18, 22609 Hamburg, Germany
| | - Wolfgang Maison
- Universität Hamburg, Department of Chemistry, Bundesstrasse 45, 20146 Hamburg, Germany.
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6
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Kher L, Kelley K, Santoro D. Ultrastructural Analysis of Differences in the Growth and Maturation of Staphylococcus pseudintermedius Biofilm on Biotic and Abiotic Surfaces. Microbiol Spectr 2023; 11:e0357722. [PMID: 36779719 PMCID: PMC10100830 DOI: 10.1128/spectrum.03577-22] [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: 09/05/2022] [Accepted: 01/16/2023] [Indexed: 02/14/2023] Open
Abstract
Biofilms are extremely complex yet systematic microbial structures. Studies comparing the differences in their growth on living and nonliving surfaces by electron microscopy are limited. Therefore, the purpose of this study was to ultrastructurally investigate the differences in the growth and development of Staphylococcal biofilm on polycarbonate filters and canine skin explants. Using scanning and transmission electron microscopy (SEM and TEM), Staphylococcus pseudintermedius was incubated for 6, 12, 24, 48, and 72 h. It was observed that similar amounts of exopolymeric substance (EPS) were deposited on the biofilm on both surfaces, but the biofilm on the skin explants was primarily flat, whereas the biofilm on the membrane developed a multilayered plateaued look. Microcolony formation was only observed on the membrane filter during the early stages of biofilm development. On the membrane biofilms, EPS was observed to be deposited in a distinctive pattern. EPS deposition on the membrane surface was observed to peak before it declined, but on the explant, a constant increase was observed at all time points. Cell exposure to the environment on both the membrane filters and explants differed depending on the stage of biofilm formation. On both the membranes and the skin explants, there was a perceptible difference between the biofilm growth patterns and speeds. The results of this study suggest that data extrapolated from studies on biofilm bactericidal compounds performed on abiotic surfaces (such as polycarbonate filters) may not be entirely applicable to biofilm growing on biotic surfaces (e.g., skin) due to ultrastructural variations revealed in this study. IMPORTANCE Biofilm has been recognized as an important source of antimicrobial resistance. These sessile microbial colonies tend to attach and grow on every surface, biotic and abiotic, and they account for approximately 80% of chronic and recurrent infections. Biofilms are not all alike; they have different structures and microbial compositions. This high variability allows for differences in the production of exopolymer substances, affecting antimicrobial penetration. No studies have been published that simultaneously compare the structure of biofilms grown on abiotic (in vitro) and biotic (ex vivo) surfaces. To identify treatment alternatives, it is essential to understand the differences between biofilms. The results of the study show how biofilm structures and compositions are dependent on the substrate on which they grow.
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Affiliation(s)
- Lopamudra Kher
- Department of Small Animal Clinical Sciences, University of Florida, Gainesville, Florida, USA
| | - Karen Kelley
- Interdisciplinary Center for Biotechnology Research (ICBR), Electron Microscopy Core Facility, University of Florida, Gainesville, Florida, USA
| | - Domenico Santoro
- Department of Small Animal Clinical Sciences, University of Florida, Gainesville, Florida, USA
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Fleeman RM, Mikesh M, Davies BW. Investigating Klebsiella pneumoniae biofilm preservation for scanning electron microscopy. Access Microbiol 2023; 5:000470.v3. [PMID: 36910511 PMCID: PMC9996182 DOI: 10.1099/acmi.0.000470.v3] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 01/02/2023] [Indexed: 02/05/2023] Open
Abstract
Klebsiella pneumoniae biofilm formation is associated with chronic and relapsing infections. Scanning electron microscopy (SEM) is a powerful tool for characterizing biofilm structure and studying their formation. Reliable visualization of biofilm structure requires careful sample preservation, otherwise there may be loss of non-covalent interactions that are susceptible to damage during the dehydration and washing preparation steps. However, no standard procedure has been adopted in the literature to fix K. pneumoniae biofilm for scanning electron microscopy studies. This lack of standardization makes it challenging to compare results between studies and determine the degree to which native structures have been preserved. To advance this critical area of study, we investigated different scanning electron microscopy fixation methods for K. pneumoniae biofilm preservation. Our study reveals the impact preparation steps can have on retaining in biofilm architecture observed using scanning electron microscopy. Using fixation methods developed through our studies, we show that although species that overproduce capsular extracellular polysaccharides produced more robust biofilms, K. pneumoniae can form a developed biofilm in the absence of capsular polysaccharides.
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Affiliation(s)
- Renee M. Fleeman
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
- Present address: Division of Immunity and Pathogenesis, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL 32837, USA
| | - Michelle Mikesh
- Center for Biomedical Research Support, The University of Texas at Austin, Austin, TX 78712, USA
| | - Bryan W. Davies
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
- Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX 78712, USA
- John Ring LaMontagne Center for Infectious Diseases, The University of Texas at Austin, Austin, TX 78712, USA
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8
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Fessia A, Sartori M, García D, Fernández L, Ponzio R, Barros G, Nesci A. In vitro studies of biofilm-forming Bacillus strains, biocontrol agents isolated from the maize phyllosphere. Biofilm 2022; 4:100097. [PMID: 36504526 PMCID: PMC9731887 DOI: 10.1016/j.bioflm.2022.100097] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 11/08/2022] [Accepted: 11/18/2022] [Indexed: 12/12/2022] Open
Abstract
We aimed to assess how biofilm formation by three Bacillus isolates was affected by changes in temperature, water potential, growth media, time, and the combinations between these factors. The strains had been selected as potential biological control agents (BCAs) in earlier studies, and they were identified as B. subtilis and B. velezensis spp. through 16 rRNA sequencing and MALDI-TOF MS. Maize leaves (ML) were used as one of the growth media, since they made it possible to simulate the nutrient content in the maize phyllosphere, from which the bacteria were originally isolated. The strains were able to form biofilm both in ML and biofilm-inducing MSgg after 24, 48, and 72 h. Biofilm development in the form of pellicles and architecturally complex colonies varied morphologically from one strain to another and depended on the conditions mentioned above. In all cases, colonies and pellicles were less complex when both temperature and water potential were lower. Scanning electron microscopy (SEM) revealed that changing levels of complexity in pellicles were correlated with those in colonies. Statistical analyses found that the quantification of biofilm produced by the isolates was influenced by all the conditions tested. In terms of motility (which may contribute to biofilm formation), swimming and swarming were possible for all strains in 0.3 and 0.7% agar, respectively. A more in-depth understanding of how abiotic factors influence biofilm formation can contribute to a more effective use of these biocontrol strains against pathogens in the maize phyllosphere.
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Affiliation(s)
- Aluminé Fessia
- Laboratorio de Ecología Microbiana, Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina,Corresponding author. Laboratorio de Ecología Microbiana, Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina.
| | - Melina Sartori
- Laboratorio de Ecología Microbiana, Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Daiana García
- Laboratorio de Ecología Microbiana, Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Luciana Fernández
- Departamento de Física, Departamento de Química, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, CONICET, X5804BYA, Río Cuarto, Argentina,Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados (IITEMA), Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Rodrigo Ponzio
- Departamento de Física, Departamento de Química, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, CONICET, X5804BYA, Río Cuarto, Argentina,Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados (IITEMA), Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Germán Barros
- Laboratorio de Ecología Microbiana, Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| | - Andrea Nesci
- Laboratorio de Ecología Microbiana, Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional 36, Km 601, X5804ZAB, Río Cuarto, Córdoba, Argentina,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
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9
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Shaffique S, Imran M, Wani SH, Khan MA, Kang SM, Adhikari A, Lee IJ. Evaluating the adhesive potential of the newly isolated bacterial strains in research exploitation of plant microbial interaction. FRONTIERS IN PLANT SCIENCE 2022; 13:1004331. [PMID: 36340407 PMCID: PMC9634002 DOI: 10.3389/fpls.2022.1004331] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 10/06/2022] [Indexed: 05/26/2023]
Abstract
Bacterial adhesion potential constitutes the transition of bacteria from the planktonic to the static phase by promoting biofilm formation, which plays a significant role in plant-microbial interaction in the agriculture industry. In present study, the adhesion potential of five soil-borne bacterial strains belonging to different genera was studied. All bacterial strains were capable of forming colonies and biofilms of different levels of firmness on polystyrene. Significant variation was observed in hydrophobicity and motility assays. Among the five bacterial strains (SH-6, SH-8, SH-9, SH-10, and SH-19), SH-19 had a strong hydrophobic force, while SH-10 showed the most hydrophilic property. SH-6 showed great variability in motility; SH-8 had a swimming diffusion diameter of 70 mm, which was three times higher than that of SH-19. In the motility assay, SH-9 and SH-10 showed diffusion diameters of approximately 22 mm and 55 mm, respectively. Furthermore, among the five strains, four are predominately electron donors and one is electron acceptors. Overall, positive correlation was observed among Lewis acid base properties, hydrophobicity, and biofilm forming ability. However, no correlation of motility with bacterial adhesion could be found in present experimental work. Scanning electron microscopy images confirmed the adhesion potential and biofilm ability within extra polymeric substances. Research on the role of adhesion in biofilm formation of bacteria isolated from plants is potentially conducive for developing strategies such as plant-microbial interaction to mitigate the abiotic stress.
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Affiliation(s)
- Shifa Shaffique
- Department of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - Muhammad Imran
- Department of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - Shabir Hussain Wani
- Mountain Research for Field Crops Khudwani, Sher-e Kashmir University of Agricultural Sciences and Technology of Kashmir, Srinagar, Jamu and Kashmir, India
| | - Muhamad Aqil Khan
- Department of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - Sang-Mo Kang
- Department of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - Arjun Adhikari
- Department of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - In-Jung Lee
- Department of Applied Biosciences, Kyungpook National University, Daegu, South Korea
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10
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Kamimura R, Kanematsu H, Ogawa A, Kogo T, Miura H, Kawai R, Hirai N, Kato T, Yoshitake M, Barry DM. Quantitative Analyses of Biofilm by Using Crystal Violet Staining and Optical Reflection. MATERIALS (BASEL, SWITZERLAND) 2022; 15:6727. [PMID: 36234069 PMCID: PMC9571847 DOI: 10.3390/ma15196727] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 07/26/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
Biofilms have caused many problems, not only in the industrial fields, but also in our daily lives. Therefore, it is important for us to control them by evaluating them properly. There are many instrumental analytical methods available for evaluating formed biofilm qualitatively. These methods include the use of Raman spectroscopy and various microscopes (optical microscopes, confocal laser microscopes, scanning electron microscopes, transmission electron microscopes, atomic force microscopes, etc.). On the other hand, there are some biological methods, such as staining, gene analyses, etc. From the practical viewpoint, staining methods seem to be the best due to various reasons. Therefore, we focused on the staining method that used a crystal violet solution. In the previous study, we devised an evaluation process for biofilms using a color meter to analyze the various staining situations. However, this method was complicated and expensive for practical engineers. For this experiment, we investigated the process of using regular photos that were quantified without any instruments except for digitized cameras. Digitized cameras were used to compare the results. As a result, we confirmed that the absolute values were different for both cases, respectively. However, the tendency of changes was the same. Therefore, we plan to utilize the changes before and after biofilm formation as indicators for the future.
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Affiliation(s)
- Ryuto Kamimura
- National Institute of Technology (KOSEN), Suzuka College, Suzuka 510-0294, Mie, Japan
| | - Hideyuki Kanematsu
- National Institute of Technology (KOSEN), Suzuka College, Suzuka 510-0294, Mie, Japan
| | - Akiko Ogawa
- National Institute of Technology (KOSEN), Suzuka College, Suzuka 510-0294, Mie, Japan
| | - Takeshi Kogo
- National Institute of Technology (KOSEN), Suzuka College, Suzuka 510-0294, Mie, Japan
| | - Hidekazu Miura
- Faculty of Medical Engineering, Suzuka University of Medical Science, Suzuka 510-0293, Mie, Japan
| | - Risa Kawai
- National Institute of Technology (KOSEN), Suzuka College, Suzuka 510-0294, Mie, Japan
| | - Nobumitsu Hirai
- National Institute of Technology (KOSEN), Suzuka College, Suzuka 510-0294, Mie, Japan
| | - Takehito Kato
- National Institute of Technology (KOSEN), Oyama College, Oyama 323-0806, Tochigi, Japan
| | - Michiko Yoshitake
- National Institute for Materials Science (NIMS), Tsukuba 305-0044, Ibaraki, Japan
| | - Dana M. Barry
- Department of Electrical & Computer Engineering, Clarkson University, Potsdam, NY 13699, USA
- STEM Laboratory, State University of New York, Canton, NY 13617, USA
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11
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Bazin D, Bouderlique E, Daudon M, Frochot V, Haymann JP, Letavernier E, Tielens F, Weil R. Scanning electron microscopy—a powerful imaging technique for the clinician. CR CHIM 2022. [DOI: 10.5802/crchim.101] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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12
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van den Berg L, Toja Ortega S, van Loosdrecht MC, de Kreuk MK. Diffusion of soluble organic substrates in aerobic granular sludge: Effect of molecular weight. WATER RESEARCH X 2022; 16:100148. [PMID: 35814501 PMCID: PMC9263526 DOI: 10.1016/j.wroa.2022.100148] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 05/17/2022] [Accepted: 06/30/2022] [Indexed: 06/15/2023]
Abstract
Aerobic granular sludge (AGS) is an advanced biofilm-based technology for wastewater treatment. Diffusion of substrates into the granules is a key aspect of this technology. Domestic wastewater contains soluble organic substrates of different sizes that could potentially diffuse into the granules. In this study, the relation between the molecular weight of a substrate and its diffusion coefficient within the granule was studied with model substrates (polyethylene glycols (PEGs) with a molecular weight between 62 and 10 000 Da). The diffusion coefficients of the model substrates within granules from a full-scale installation were measured with the 'transient uptake of a non-reactive solute' method. The diffusion coefficients in the granules were not significantly different from the diffusion coefficients in water, at least up to 4000 Da molecular weight. This indicates that these PEGs were not obstructed by the granule matrix. The 10 kDa PEG behaved differently from the lighter PEGs, as it could not penetrate the entire granule. Furthermore, the granule structure was characterized with Environmental Scanning Electron Microscopy (ESEM). The granules displayed an open structure with large macropores and semi-solid regions, which contained microbial cells. The diffusion results suggest that most diffusing molecules were unobstructed in the macropores and barely obstructed in the semi-solid regions. Only the diffusion of the 10 kDa PEG seemed to be hindered by the semi-solid regions, but not by the macropores. Lastly, the apparent molecular weight distribution of domestic wastewater soluble COD was determined with ultrafiltration membranes of 100, 10, and 1 kDa molecular weight cut-off. The influent fractionation revealed that a large part (61-69%) of the influent soluble COD was lighter than 1 kDa. As molecules lighter than 1 kDa diffuse easily, the majority of the influent soluble COD can be considered as diffusible COD. These findings provide new insight into the availability of influent COD for granular sludge.
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Affiliation(s)
- Lenno van den Berg
- Department of Water Management, Delft University of Technology, the Netherlands
| | - Sara Toja Ortega
- Department of Water Management, Delft University of Technology, the Netherlands
| | | | - Merle K. de Kreuk
- Department of Water Management, Delft University of Technology, the Netherlands
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13
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Kudara H, Kanematsu H, Barry DM, Ogawa A, Kogo T, Miura H, Kawai R, Hirai N, Kato T, Yoshitake M. Proposal for Some Affordable Laboratory Biofilm Reactors and Their Critical Evaluations from Practical Viewpoints. MATERIALS 2022; 15:ma15134691. [PMID: 35806818 PMCID: PMC9267959 DOI: 10.3390/ma15134691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 06/15/2022] [Accepted: 06/16/2022] [Indexed: 11/16/2022]
Abstract
Biofilms are a result of bacterial activities and are found everywhere. They often form on metal surfaces and on the surfaces of polymeric compounds. Biofilms are sticky and mostly consist of water. They have a strong resistance to antimicrobial agents and can cause serious problems for modern medicine and industry. Biofilms are composed of extracellular polymeric substances (EPS) such as polysaccharides produced from bacterial cells and are dominated by water at the initial stage. In a series of experiments, using Escherichia coli, we developed three types of laboratory biofilm reactors (LBR) to simulate biofilm formation. For the first trial, we used a rotary type of biofilm reactor for stirring. For the next trial, we tried another rotary type of reactor where the circular plate holding specimens was rotated. Finally, a circular laboratory biofilm reactor was used. Biofilms were evaluated by using a crystal violet staining method and by using Raman spectroscopy. Additionally, they were compared to each other from the practical (industrial) viewpoints. The third type was the best to form biofilms in a short period. However, the first and second were better from the viewpoint of “ease of use”. All of these have their own advantages and disadvantages, respectively. Therefore, they should be properly selected and used for specific and appropriate purposes in the future.
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Affiliation(s)
- Hikonaru Kudara
- National Institute of Technology (KOSEN), Suzuka College, Suzuka 510-0294, Japan; (H.K.); (A.O.); (T.K.); (R.K.); (N.H.)
| | - Hideyuki Kanematsu
- National Institute of Technology (KOSEN), Suzuka College, Suzuka 510-0294, Japan; (H.K.); (A.O.); (T.K.); (R.K.); (N.H.)
- Correspondence: ; Tel.: +81-59-368-1848
| | - Dana M. Barry
- Department of Electrical & Computer Engineering, Clarkson University, Potsdam, NY 13699, USA;
- STEM Laboratory, State University of New York, Canton, NY 13617, USA
| | - Akiko Ogawa
- National Institute of Technology (KOSEN), Suzuka College, Suzuka 510-0294, Japan; (H.K.); (A.O.); (T.K.); (R.K.); (N.H.)
| | - Takeshi Kogo
- National Institute of Technology (KOSEN), Suzuka College, Suzuka 510-0294, Japan; (H.K.); (A.O.); (T.K.); (R.K.); (N.H.)
| | - Hidekazu Miura
- Faculty of Medical Engineering, Suzuka University of Medical Science, Suzuka 510-0293, Japan;
| | - Risa Kawai
- National Institute of Technology (KOSEN), Suzuka College, Suzuka 510-0294, Japan; (H.K.); (A.O.); (T.K.); (R.K.); (N.H.)
| | - Nobumitsu Hirai
- National Institute of Technology (KOSEN), Suzuka College, Suzuka 510-0294, Japan; (H.K.); (A.O.); (T.K.); (R.K.); (N.H.)
| | - Takehito Kato
- National Institute of Technology (KOSEN), Oyama College, Oyama 323-0806, Japan;
| | - Michiko Yoshitake
- National Institute for Materials Science (NIMS), Tsukuba 305-0044, Japan;
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Impedance Characteristics of Monolayer and Bilayer Graphene Films with Biofilm Formation and Growth. SENSORS 2022; 22:s22093548. [PMID: 35591238 PMCID: PMC9101136 DOI: 10.3390/s22093548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 04/09/2022] [Accepted: 04/11/2022] [Indexed: 11/17/2022]
Abstract
Biofilms are the result of bacterial activity. When the number of bacteria (attached to materials’ surfaces) reaches a certain threshold value, then the bacteria simultaneously excrete organic polymers (EPS: extracellular polymeric substances). These sticky polymers encase and protect the bacteria. They are called biofilms and contain about 80% water. Other components of biofilm include polymeric carbon compounds such as polysaccharides and bacteria. It is well-known that biofilms cause various medical and hygiene problems. Therefore, it is important to have a sensor that can detect biofilms to solve such problems. Graphene is a single-atom-thick sheet in which carbon atoms are connected in a hexagonal shape like a honeycomb. Carbon compounds generally bond easily to graphene. Therefore, it is highly possible that graphene could serve as a sensor to monitor biofilm formation and growth. In our previous study, monolayer graphene was prepared on a glass substrate by the chemical vapor deposition (CVD) method. Its biofilm forming ability was compared with that of graphite. As a result, the CVD graphene film had the higher sensitivity for biofilm formation. However, the monolayer graphene has a mechanical disadvantage when used as a biofilm sensor. Therefore, for this new research project, we prepared bilayer graphene with high mechanical strength by using the CVD process on copper substrates. For these specimens, we measured the capacitance component of the specimens’ impedance. In addition, we have included a discussion about the possibility of applying them as future sensors for monitoring biofilm formation and growth.
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15
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Boutsioukis C, Arias-Moliz MT, Chávez de Paz LE. A critical analysis of research methods and experimental models to study irrigants and irrigation systems. Int Endod J 2022; 55 Suppl 2:295-329. [PMID: 35171506 PMCID: PMC9314845 DOI: 10.1111/iej.13710] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 02/07/2022] [Accepted: 02/08/2022] [Indexed: 11/28/2022]
Abstract
Irrigation plays an essential role in root canal treatment. The purpose of this narrative review was to critically appraise the experimental methods and models used to study irrigants and irrigation systems and to provide directions for future research. Studies on the antimicrobial effect of irrigants should use mature multispecies biofilms grown on dentine or inside root canals and should combine at least two complementary evaluation methods. Dissolution of pulp tissue remnants should be examined in the presence of dentine and, preferably, inside human root canals. Micro-omputed tomography is currently the method of choice for the assessment of accumulated dentine debris and their removal. A combination of experiments in transparent root canals and numerical modeling is needed to address irrigant penetration. Finally, models to evaluate irrigant extrusion through the apical foramen should simulate the periapical tissues and provide quantitative data on the amount of extruded irrigant. Mimicking the in vivo conditions as close as possible and standardization of the specimens and experimental protocols are universal requirements irrespective of the surrogate endpoint studied. Obsolete and unrealistic models must be abandoned in favour of more appropriate and valid ones that have more direct application and translation to clinical Endodontics.
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Affiliation(s)
- C Boutsioukis
- Department of Endodontology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - M T Arias-Moliz
- Department of Microbiology, Faculty of Dentistry, University of Granada, Granada, Spain
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16
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Shi X, Sharma V, Cantu-Crouch D, Yao G, Fukazawa K, Ishihara K, Wu JY. Nanoscaled Morphology and Mechanical Properties of a Biomimetic Polymer Surface on a Silicone Hydrogel Contact Lens. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:13961-13967. [PMID: 34788044 DOI: 10.1021/acs.langmuir.1c02678] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Materials taking advantage of the characteristics of biological tissues are strongly sought after in medical science and bioscience. On the natural corneal tissue surface, the highly soft and lubricated surface is maintained by composite structures composed of hydrophilic biomolecules and substrates. To mimic this structure, the surface of a silicone hydrogel contact lens was modified with a biomimetic phospholipid polymer, poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), and the nanoscaled morphology and mechanical properties of the surface were confirmed with advanced surface characterization and imaging techniques under an aqueous medium. Concavities and convexities on the nanometer order were recognized on the surface. The surface was completely covered with a PMPC layer and remained intact even after 30 days of clinical use in a human ocular environment. The mechanical properties of the natural corneal tissue and the PMPC-modified surface were similar in the living environment, that is, low modulus and frictional properties comparable to natural tissues. These results show the validity of material preparation by biomimetic methods. The methodologies developed in this study may contribute to future development of human-friendly medical devices.
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Affiliation(s)
- Xinfeng Shi
- Alcon Research, Limited Liability Company, Fort Worth, Texas 76134, United States
| | - Vinay Sharma
- Alcon Research, Limited Liability Company, Fort Worth, Texas 76134, United States
| | - David Cantu-Crouch
- Alcon Research, Limited Liability Company, Fort Worth, Texas 76134, United States
| | - George Yao
- Alcon Research, Limited Liability Company, Duluth, Georgia 30097, United States
| | - Kyoko Fukazawa
- Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Kazuhiko Ishihara
- Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - James Yuliang Wu
- Alcon Research, Limited Liability Company, Fort Worth, Texas 76134, United States
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Garg A, Mala K, Kamath PM. Biofilm models in endodontics-A narrative review. J Conserv Dent 2021; 24:2-9. [PMID: 34475672 PMCID: PMC8378488 DOI: 10.4103/jcd.jcd_621_20] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/12/2021] [Accepted: 02/19/2021] [Indexed: 11/22/2022] Open
Abstract
The knowledge of biofilm and its eradication from the root canal system are of utmost importance in the clinical practice of an endodontist. Various treatment strategies and protocols have been demonstrated and discussed by numerous clinicians and researchers, on these models, that play an important role in the treatment outcome . Once a biofilm model is developed by considering various factors, several methods can be used to assess the biofilms formed on these models. This review discusses the importance of biofilm models in endodontics, types of biofilm models and factors associated with developing and the methods to evaluate these models.
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Affiliation(s)
- Anirudh Garg
- Department of Conservative Dentistry and Endodontics, Manipal College of Dental Sciences,Mangalore, Affiliated to Manipal Academy of Higher Education, Mangalore, Karnataka, India
| | - Kundabala Mala
- Department of Conservative Dentistry and Endodontics, Manipal College of Dental Sciences,Mangalore, Affiliated to Manipal Academy of Higher Education, Mangalore, Karnataka, India
| | - Priyanka Madhav Kamath
- Department of Conservative Dentistry and Endodontics, Manipal College of Dental Sciences,Mangalore, Affiliated to Manipal Academy of Higher Education, Mangalore, Karnataka, India
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18
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Perry TW. Cutaneous microbial biofilm formation as an underlying cause of red scrotum syndrome. Eur J Med Res 2021; 26:95. [PMID: 34412706 PMCID: PMC8375042 DOI: 10.1186/s40001-021-00569-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 08/09/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Red scrotum syndrome is typically described as well-demarcated erythema of the anterior scrotum accompanied by persistent itching and burning. It is chronic and difficult to treat and contributes to significant psychological distress and reduction in quality of life. The medical literature surrounding the condition is sparse, with the prevalence likely under-recognized and the pathophysiology remaining poorly understood. Formation of a cutaneous microbial biofilm has not been proposed as an underlying etiology. Microbial biofilms can form whenever microorganisms are suspended in fluid on a surface for a prolonged time and are becoming increasingly recognized as important contributors to medical disease (e.g., chronic wounds). CASE PRESENTATION A 26-year-old man abruptly developed well-demarcated erythema of the bilateral scrotum after vaginal secretions were left covering the scrotum overnight. For 14 months, the patient experienced daily scrotal itching and burning while seeking care from multiple physicians and attempting numerous failed therapies. He eventually obtained complete symptomatic relief with the twice daily application of 0.8% menthol powder. Findings in support of a cutaneous microbial biofilm as the underlying etiology include: (1) the condition began following a typical scenario that would facilitate biofilm formation; (2) the demarcation of erythema precisely follows the scrotal hairline, suggesting that hair follicles acted as scaffolding during biofilm formation; (3) despite resolution of symptoms, the scrotal erythema has persisted, unchanged in boundary 15 years after the condition began; and (4) the erythematous skin demonstrates prolonged retention of gentian violet dye in comparison with adjacent unaffected skin, suggesting the presence of dye-avid material on the skin surface. CONCLUSION The probability that microorganisms, under proper conditions, can form biofilm on intact skin is poorly recognized. This case presents a compelling argument for a cutaneous microbial biofilm as the underlying cause of red scrotum syndrome in one patient, and a review of similarities with other reported cases suggests the same etiology is likely responsible for a significant portion of the total disease burden. This etiology may also be a significant contributor to the disease burden of vulvodynia, a condition with many similarities to red scrotum syndrome.
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Affiliation(s)
- Theodore W Perry
- Fee-Basis Hospitalist, North Texas VA Medical Center, 4500 South Lancaster Road, TX, 75216, Dallas, USA.
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19
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Colboc H, Fontaine J, Bazin D, Frochot V, Letavernier E, Daudon M, Laporte N, Rouzière S, Reby M, Galezowski A, Forasassi C, Meaume S. Calcified leg Ulcers in older patients: clinical description, morphology and chemical characterization. J Gerontol A Biol Sci Med Sci 2021; 77:27-32. [PMID: 34331540 DOI: 10.1093/gerona/glab223] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Indexed: 11/14/2022] Open
Abstract
Chronic wounds, including leg ulcers, constitute an important medical problem among older patients. Dystrophic calcifications (DC) are associated with a variety of disorders, including leg ulcers. The aim of this study was to report the clinical and biological characteristics of older patients with DC in leg ulcers and to determine the morphology and chemical composition of these calcifications. We conducted a prospective monocentric study in our Geriatric-Wound and Healing ward, Rothschild Hospital, Paris, from January 2018 to December 2019. Patients with leg ulcers were screened for DC by palpation. Patients' clinical, biological and radiological findings were collected. DC morphology was analyzed using field-emission scanning electron microscopy and chemical composition was analyzed using µFourier transform infra-red spectroscopy and X-ray Fluorescence. Ten (7%) of the 143 patients hospitalized for leg ulcers presented DC. Older patients with DC were more likely to have leg ulcers with venous insufficiency (P=0.015), colonized by Pseudomonas aeruginosa (P=0.026), with a longer healing evolution (P=0.0072) and hypercalcemia (P=0.041). Five DC were extracted from ulcers: two presented 500 nm lacunar spheres and intermingled fibrils of about 10 nm in diameter, consistent with bacterial and biofilm imprints. DC were always composed of Calcium-phosphate apatite and associated to the presence of Zinc. Our analyses were consistent with the involvement of microorganisms and inflammatory process in DC formation. Early management of venous insufficiency, treatment of chronic bacterial colonization and use of calcium-solubilizing drugs seem to be rational strategies for calcified leg ulcer management in older patients.
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Affiliation(s)
- Hester Colboc
- Sorbonne Université, Hôpital Rothschild, Service Plaies et Cicatrisation, Paris, France
| | - Juliette Fontaine
- Sorbonne Université, Hôpital Rothschild, Service Plaies et Cicatrisation, Paris, France
| | | | - Vincent Frochot
- Sorbonne Université, Hôpital Tenon, Service des Explorations Fonctionnelles Multidisciplinaires, Paris, France.,UMR_S 1155, Sorbonne Université-UPMC Paris 06, F-75020 Paris, France
| | - Emmanuel Letavernier
- Sorbonne Université, Hôpital Tenon, Service des Explorations Fonctionnelles Multidisciplinaires, Paris, France.,UMR_S 1155, Sorbonne Université-UPMC Paris 06, F-75020 Paris, France
| | - Michel Daudon
- Sorbonne Université, Hôpital Tenon, Service des Explorations Fonctionnelles Multidisciplinaires, Paris, France.,UMR_S 1155, Sorbonne Université-UPMC Paris 06, F-75020 Paris, France
| | - Naomi Laporte
- Sorbonne Université, Hôpital Rothschild, Service Plaies et Cicatrisation, Paris, France
| | - Stéphan Rouzière
- Laboratoire de Physique des Solides, CNRS, Université Paris-Saclay, Orsay, France
| | - Michael Reby
- Sorbonne Université, Hôpital Rothschild, Service Plaies et Cicatrisation, Paris, France
| | - Agnes Galezowski
- Sorbonne Université, Hôpital Rothschild, Service Plaies et Cicatrisation, Paris, France
| | - Christine Forasassi
- Sorbonne Université, Hôpital Rothschild, Service Plaies et Cicatrisation, Paris, France
| | - Sylvie Meaume
- Sorbonne Université, Hôpital Rothschild, Service Plaies et Cicatrisation, Paris, France
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20
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Awadh AA, Kelly AF, Forster-Wilkins G, Wertheim D, Giddens R, Gould SW, Fielder MD. Visualisation and biovolume quantification in the characterisation of biofilm formation in Mycoplasma fermentans. Sci Rep 2021; 11:11259. [PMID: 34045521 PMCID: PMC8160185 DOI: 10.1038/s41598-021-90455-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 04/28/2021] [Indexed: 11/09/2022] Open
Abstract
The ability of mycoplasmas to persist on surfaces has been widely acknowledged, despite their fastidious nature. However, the organism's capability to form a recognisable biofilm structure has been identified more recently. In the current study Mycoplasma fermentans was found to adhere to the glass surface forming highly differentiated biofilm structures. The volumes of biofilm microcolonies were quantified and observed to be greater at late growth stage than those at early growth stage. The channel diameters within biofilms were measured with Scanning Electron Microscopy images and found to be consistent with the size observed in Confocal Laser Scanning Microscope images. The combination of imaging methods with 3D visualisation provides key findings that aid understanding of the mycoplasma biofilm formation and true biofilm architecture. The observations reported here provide better understanding of the persistence of these minimalist pathogens in nature and clinical settings.
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Affiliation(s)
- Ammar A Awadh
- School of Life Science Pharmacy, Chemistry Faculty of Science, Engineering and Computing, Kingston University London, Kingston, UK
| | - Alison F Kelly
- School of Life Science Pharmacy, Chemistry Faculty of Science, Engineering and Computing, Kingston University London, Kingston, UK
| | - Gary Forster-Wilkins
- School of Life Science Pharmacy, Chemistry Faculty of Science, Engineering and Computing, Kingston University London, Kingston, UK
| | - David Wertheim
- School of Computer Science and Mathematics, Chemistry Faculty of Science, Engineering and Computing, Kingston University London, Kingston, UK
| | - Richard Giddens
- School of Life Science Pharmacy, Chemistry Faculty of Science, Engineering and Computing, Kingston University London, Kingston, UK
| | - Simon W Gould
- School of Life Science Pharmacy, Chemistry Faculty of Science, Engineering and Computing, Kingston University London, Kingston, UK
| | - Mark D Fielder
- School of Life Science Pharmacy, Chemistry Faculty of Science, Engineering and Computing, Kingston University London, Kingston, UK.
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21
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Asghari E, Kiel A, Kaltschmidt BP, Wortmann M, Schmidt N, Hüsgen B, Hütten A, Knabbe C, Kaltschmidt C, Kaltschmidt B. Identification of Microorganisms from Several Surfaces by MALDI-TOF MS: P. aeruginosa Is Leading in Biofilm Formation. Microorganisms 2021; 9:microorganisms9050992. [PMID: 34064414 PMCID: PMC8147854 DOI: 10.3390/microorganisms9050992] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 04/29/2021] [Accepted: 05/02/2021] [Indexed: 01/10/2023] Open
Abstract
New ecological trends and changes in consumer behavior are known to favor biofilm formation in household appliances, increasing the need for new antimicrobial materials and surfaces. Their development requires laboratory-cultivated biofilms, or biofilm model systems (BMS), which allow for accelerated growth and offer better understanding of the underlying formation mechanisms. Here, we identified bacterial strains in wildtype biofilms from a variety of materials from domestic appliances using matrix-assisted laser desorption/ionization-time of flight mass spectroscopy (MALDI-TOF-MS). Staphylococci and pseudomonads were identified by MALDI-TOF-MS as the main genera in the habitats and were analyzed for biofilm formation using various in vitro methods. Standard quantitative biofilm assays were combined with scanning electron microscopy (SEM) to characterize biofilm formation. While Pseudomonas putida, a published lead germ, was not identified in any of the collected samples, Pseudomonas aeruginosa was found to be the most dominant biofilm producer. Water-born Pseudomonads were dominantly found in compartments with water contact only, such as in detergent compartment and detergent enemata. Furthermore, materials in contact with the washing load are predominantly colonized with bacteria from the human.
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Affiliation(s)
- Ehsan Asghari
- Department of Cell Biology, Faculty of Biology, University of Bielefeld, 33615 Bielefeld, Germany; (E.A.); (A.K.); (C.K.)
| | - Annika Kiel
- Department of Cell Biology, Faculty of Biology, University of Bielefeld, 33615 Bielefeld, Germany; (E.A.); (A.K.); (C.K.)
| | - Bernhard Peter Kaltschmidt
- Department of Thin Films & Physics of Nanostructures, Center of Spinelectronic Materials and Devices, Faculty of Physics, University of Bielefeld, 33615 Bielefeld, Germany; (B.P.K.); (A.H.)
| | - Martin Wortmann
- Department of Plastics Technology, University of Applied Sciences, 33619 Bielefeld, Germany; (M.W.); (B.H.)
| | - Nadine Schmidt
- Institute for Laboratory- and Transfusion Medicine, Heart- and Diabetes Centre NRW, Ruhr-University Bochum, 32545 Bad Oeynhausen, Germany; (N.S.); (C.K.)
| | - Bruno Hüsgen
- Department of Plastics Technology, University of Applied Sciences, 33619 Bielefeld, Germany; (M.W.); (B.H.)
| | - Andreas Hütten
- Department of Thin Films & Physics of Nanostructures, Center of Spinelectronic Materials and Devices, Faculty of Physics, University of Bielefeld, 33615 Bielefeld, Germany; (B.P.K.); (A.H.)
| | - Cornelius Knabbe
- Institute for Laboratory- and Transfusion Medicine, Heart- and Diabetes Centre NRW, Ruhr-University Bochum, 32545 Bad Oeynhausen, Germany; (N.S.); (C.K.)
| | - Christian Kaltschmidt
- Department of Cell Biology, Faculty of Biology, University of Bielefeld, 33615 Bielefeld, Germany; (E.A.); (A.K.); (C.K.)
| | - Barbara Kaltschmidt
- Department of Cell Biology, Faculty of Biology, University of Bielefeld, 33615 Bielefeld, Germany; (E.A.); (A.K.); (C.K.)
- Correspondence:
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22
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Athmika, Ghate SD, Arun AB, Rao SS, Kumar STA, Kandiyil MK, Saptami K, Rekha PD. Genome analysis of a halophilic bacterium Halomonas malpeensis YU-PRIM-29 T reveals its exopolysaccharide and pigment producing capabilities. Sci Rep 2021; 11:1749. [PMID: 33462335 PMCID: PMC7814019 DOI: 10.1038/s41598-021-81395-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 01/04/2021] [Indexed: 11/08/2022] Open
Abstract
Halomonas malpeensis strain YU-PRIM-29T is a yellow pigmented, exopolysaccharide (EPS) producing halophilic bacterium isolated from the coastal region. To understand the biosynthesis pathways involved in the EPS and pigment production, whole genome analysis was performed. The complete genome sequencing and the de novo assembly were carried out using Illumina sequencing and SPAdes genome assembler (ver 3.11.1) respectively followed by detailed genome annotation. The genome consists of 3,607,821 bp distributed in 18 contigs with 3337 protein coding genes and 53% of the annotated CDS are having putative functions. Gene annotation disclosed the presence of genes involved in ABC transporter-dependent pathway of EPS biosynthesis. As the ABC transporter-dependent pathway is also implicated in the capsular polysaccharide (CPS) biosynthesis, we employed extraction protocols for both EPS (from the culture supernatants) and CPS (from the cells) and found that the secreted polysaccharide i.e., EPS was predominant. The EPS showed good emulsifying activities against the petroleum hydrocarbons and its production was dependent on the carbon source supplied. The genome analysis also revealed genes involved in industrially important metabolites such as zeaxanthin pigment, ectoine and polyhydroxyalkanoate (PHA) biosynthesis. To confirm the genome data, we extracted these metabolites from the cultures and successfully identified them. The pigment extracted from the cells showed the distinct UV-Vis spectra having characteristic absorption peak of zeaxanthin (λmax 448 nm) with potent antioxidant activities. The ability of H. malpeensis strain YU-PRIM-29T to produce important biomolecules makes it an industrially important bacterium.
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Affiliation(s)
- Athmika
- Yenepoya Research Centre, Yenepoya (Deemed to be University), University Road, Deralakatte, Mangalore, 575018, India
| | - Sudeep D Ghate
- Yenepoya Research Centre, Yenepoya (Deemed to be University), University Road, Deralakatte, Mangalore, 575018, India
| | - A B Arun
- Yenepoya Research Centre, Yenepoya (Deemed to be University), University Road, Deralakatte, Mangalore, 575018, India
| | - Sneha S Rao
- Yenepoya Research Centre, Yenepoya (Deemed to be University), University Road, Deralakatte, Mangalore, 575018, India
| | - S T Arun Kumar
- Yenepoya Research Centre, Yenepoya (Deemed to be University), University Road, Deralakatte, Mangalore, 575018, India
| | - Mrudula Kinarulla Kandiyil
- Yenepoya Research Centre, Yenepoya (Deemed to be University), University Road, Deralakatte, Mangalore, 575018, India
| | - Kanekar Saptami
- Yenepoya Research Centre, Yenepoya (Deemed to be University), University Road, Deralakatte, Mangalore, 575018, India
| | - P D Rekha
- Yenepoya Research Centre, Yenepoya (Deemed to be University), University Road, Deralakatte, Mangalore, 575018, India.
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Relucenti M, Familiari G, Donfrancesco O, Taurino M, Li X, Chen R, Artini M, Papa R, Selan L. Microscopy Methods for Biofilm Imaging: Focus on SEM and VP-SEM Pros and Cons. BIOLOGY 2021; 10:biology10010051. [PMID: 33445707 PMCID: PMC7828176 DOI: 10.3390/biology10010051] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 12/30/2020] [Accepted: 01/07/2021] [Indexed: 12/11/2022]
Abstract
Simple Summary Bacterial biofilms cause infections that are often resistant to antibiotic treatments. Research about the formation and elimination of biofilms cannot be undertaken without detailed imaging techniques. In this review, traditional and cutting-edge microscopy methods to study biofilm structure, ultrastructure, and 3-D architecture, with particular emphasis on conventional scanning electron microscopy and variable pressure scanning electron microscopy, are addressed, with the respective advantages and disadvantages. When ultrastructural characterization of biofilm matrix and its embedded bacterial cells is needed, as in studies on the effects of drug treatments on biofilm, scanning electron microscopy with customized protocols such as the osmium tetroxide (OsO4), ruthenium red (RR), tannic acid (TA), and ionic liquid (IL) must be preferred over other methods for the following: unparalleled image quality, magnification and resolution, minimal sample loss, and actual sample structure preservation. The first step to make a morphological assessment of the effect of the various pharmacological treatments on clinical biofilms is the production of images that faithfully reflect the structure of the sample. The extraction of quantitative parameters from images, possible using specific software, will allow for the scanning electron microscopy morphological evaluation to no longer be considered as an accessory technique, but a quantitative method to all effects. Abstract Several imaging methodologies have been used in biofilm studies, contributing to deepening the knowledge on their structure. This review illustrates the most widely used microscopy techniques in biofilm investigations, focusing on traditional and innovative scanning electron microscopy techniques such as scanning electron microscopy (SEM), variable pressure SEM (VP-SEM), environmental SEM (ESEM), and the more recent ambiental SEM (ASEM), ending with the cutting edge Cryo-SEM and focused ion beam SEM (FIB SEM), highlighting the pros and cons of several methods with particular emphasis on conventional SEM and VP-SEM. As each technique has its own advantages and disadvantages, the choice of the most appropriate method must be done carefully, based on the specific aim of the study. The evaluation of the drug effects on biofilm requires imaging methods that show the most detailed ultrastructural features of the biofilm. In this kind of research, the use of scanning electron microscopy with customized protocols such as osmium tetroxide (OsO4), ruthenium red (RR), tannic acid (TA) staining, and ionic liquid (IL) treatment is unrivalled for its image quality, magnification, resolution, minimal sample loss, and actual sample structure preservation. The combined use of innovative SEM protocols and 3-D image analysis software will allow for quantitative data from SEM images to be extracted; in this way, data from images of samples that have undergone different antibiofilm treatments can be compared.
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Affiliation(s)
- Michela Relucenti
- Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Sapienza University of Rome, Via Alfonso Borelli 50, 00161 Rome, Italy; (G.F.); (O.D.)
- Correspondence: ; Tel.: +39-0649918061
| | - Giuseppe Familiari
- Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Sapienza University of Rome, Via Alfonso Borelli 50, 00161 Rome, Italy; (G.F.); (O.D.)
| | - Orlando Donfrancesco
- Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Sapienza University of Rome, Via Alfonso Borelli 50, 00161 Rome, Italy; (G.F.); (O.D.)
| | - Maurizio Taurino
- Department of Clinical and Molecular Medicine, Unit of Vascular Surgery, Sant’Andrea Hospital, Sapienza University of Rome, Via di Grottarossa 1039, 00189 Rome, Italy;
| | - Xiaobo Li
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210096, China; (X.L.); (R.C.)
| | - Rui Chen
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210096, China; (X.L.); (R.C.)
| | - Marco Artini
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy; (M.A.); (R.P.); (L.S.)
| | - Rosanna Papa
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy; (M.A.); (R.P.); (L.S.)
| | - Laura Selan
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy; (M.A.); (R.P.); (L.S.)
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24
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Shi X, Cantu-Crouch D, Sharma V, Pruitt J, Yao G, Fukazawa K, Wu JY, Ishihara K. Surface characterization of a silicone hydrogel contact lens having bioinspired 2-methacryloyloxyethyl phosphorylcholine polymer layer in hydrated state. Colloids Surf B Biointerfaces 2021; 199:111539. [PMID: 33387797 DOI: 10.1016/j.colsurfb.2020.111539] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/14/2020] [Accepted: 12/15/2020] [Indexed: 01/08/2023]
Abstract
A silicone hydrogel contact lens material, with a unique chemical and physical structure has been designed for long-term ocular performance. Enhancement of this silicone hydrogel contact lens material was achieved through surface modification using a cross-linkable bioinspired 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer, which creates a soft surface gel layer on the silicone hydrogel base material. The surface properties of this MPC polymer-modified lens were characterized under hydrated condition revealing, inter alia, its unique polymer structure, excellent hydrophilicity, lubricity, and flexibility. Analysis of the MPC polymer layer in a hydrated state was performed using a combination of a high-resolution environmental scanning electron microscopy and atomic force microscopy. Compared to the silicone hydrogel base material, this surface had a higher captive bubble contact angle, which corresponds to higher hydrophilicity of the surface. In addition, the hydrated MPC polymer layer exhibited an extremely soft surface and reduced the coefficient of friction by more than 80 %. These characteristics were attributed to the hydration state of the MPC polymer layer on the surface of the silicone hydrogel base material. Also, interaction force of protein deposition was lowered on the surface. Such superior surface properties are anticipated to contribute to excellent ocular performance.
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Affiliation(s)
- Xinfeng Shi
- Alcon Vision, LLC, Fort Worth, TX, 76134, USA
| | | | | | | | - George Yao
- Alcon Vision, LLC, Duluth, GA, 30097, USA
| | - Kyoko Fukazawa
- Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | | | - Kazuhiko Ishihara
- Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
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25
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Ahamed T, Brown SP, Salehi M. Investigate the role of biofilm and water chemistry on lead deposition onto and release from polyethylene: An implication for potable water pipes. JOURNAL OF HAZARDOUS MATERIALS 2020; 400:123253. [PMID: 32947746 DOI: 10.1016/j.jhazmat.2020.123253] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 06/16/2020] [Accepted: 06/17/2020] [Indexed: 06/11/2023]
Abstract
In this study, the influence of biofilm presence and water chemistry conditions on lead (Pb) deposition onto low density polyethylene (LDPE) surface was examined. The results demonstrated that biofilm presence on LDPE surfaces strongly and significantly enhanced Pb uptake, with the 13-fold greater equilibrium Pb surface loading when biofilm was present (1602 μg/m2) compared to the condition when it was absent (124 μg/m2). The kinetics of Pb adsorption onto LDPE surface when biofilm was present is best described by Pseudo 2nd order kinetic model. Pb adsorption onto new LDPE surfaces was significantly reduced from 1101 μg/m2 to 134 μg/m2 with increased aqueous solution's ionic strength from 3 × 10-6 M to 0.0072 M. The presence of chlorine residual (2 mg/L) significantly reduced Pb adsorption onto LDPE surfaces by possible oxidation of Pb2+ to Pb4+ species. The kinetics of Pb release from LDPE surfaces was investigated under static and dynamic conditions through immediate exposure of Pb accumulated LDPE pellets to the synthetic water at pH 5.0 and 7.8. The results demonstrated a greater Pb release (86 %) at pH 5.0 compared to the pH 7.8 (58 %). An enhanced Pb release into the contact water was found under dynamic conditions compared to static conditions.
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Affiliation(s)
- Tanvir Ahamed
- Department of Civil Engineering, The University of Memphis, Memphis, TN, USA
| | - Shawn P Brown
- Department of Biological Sciences, The University of Memphis, Memphis, TN, USA
| | - Maryam Salehi
- Department of Civil Engineering, The University of Memphis, Memphis, TN, USA.
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26
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Majumdar M, Dubey A, Goswami R, Misra TK, Roy DN. In vitro and in silico studies on the structural and biochemical insight of anti-biofilm activity of andrograpanin from Andrographis paniculata against Pseudomonas aeruginosa. World J Microbiol Biotechnol 2020; 36:143. [DOI: 10.1007/s11274-020-02919-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 08/18/2020] [Indexed: 01/10/2023]
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27
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Achinas S, Yska SK, Charalampogiannis N, Krooneman J, Euverink GJW. A Technological Understanding of Biofilm Detection Techniques: A Review. MATERIALS (BASEL, SWITZERLAND) 2020; 13:E3147. [PMID: 32679710 PMCID: PMC7412299 DOI: 10.3390/ma13143147] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/08/2020] [Accepted: 07/13/2020] [Indexed: 12/12/2022]
Abstract
Biofouling is a persistent problem in almost any water-based application in several industries. To eradicate biofouling-related problems in bioreactors, the detection of biofilms is necessary. The current literature does not provide clear supportive information on selecting biofilm detection techniques that can be applied to detect biofouling within bioreactors. Therefore, this research aims to review all available biofilm detection techniques and analyze their characteristic properties to provide a comparative assessment that researchers can use to find a suitable biofilm detection technique to investigate their biofilms. In addition, it discusses the confluence of common bioreactor fabrication materials in biofilm formation.
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Affiliation(s)
- Spyridon Achinas
- Faculty of Science and Engineering, University of Groningen, 9747 AG Groningen, The Netherlands; (S.K.Y.); (J.K.); (G.J.W.E.)
| | - Stijn Keimpe Yska
- Faculty of Science and Engineering, University of Groningen, 9747 AG Groningen, The Netherlands; (S.K.Y.); (J.K.); (G.J.W.E.)
| | | | - Janneke Krooneman
- Faculty of Science and Engineering, University of Groningen, 9747 AG Groningen, The Netherlands; (S.K.Y.); (J.K.); (G.J.W.E.)
| | - Gerrit Jan Willem Euverink
- Faculty of Science and Engineering, University of Groningen, 9747 AG Groningen, The Netherlands; (S.K.Y.); (J.K.); (G.J.W.E.)
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Characterization of Scardovia wiggsiae Biofilm by Original Scanning Electron Microscopy Protocol. Microorganisms 2020; 8:microorganisms8060807. [PMID: 32471210 PMCID: PMC7355790 DOI: 10.3390/microorganisms8060807] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 05/22/2020] [Accepted: 05/26/2020] [Indexed: 01/11/2023] Open
Abstract
Early childhood caries (ECC) is a severe manifestation of carious pathology with rapid and disruptive progression. The ECC microbiota includes a wide variety of bacterial species, among which is an anaerobic newly named species, Scardovia wiggsiae, a previously unidentified Bifidobacterium. Our aim was to provide the first ultrastructural characterization of S. wiggsiae and its biofilm by scanning electron microscopy (SEM) using a protocol that faithfully preserved the biofilm architecture and allowed an investigation at very high magnifications (order of nanometers) and with the appropriate resolution. To accomplish this task, we analyzed Streptococcus mutans’ biofilm by conventional SEM and VP-SEM protocols, in addition, we developed an original procedure, named OsO4-RR-TA-IL, which avoids dehydration, drying and sputter coating. This innovative protocol allowed high-resolution and high-magnification imaging (from 10000× to 35000×) in high-vacuum and high-voltage conditions. After comparing three methods, we chose OsO4-RR-TA-IL to investigate S. wiggsiae. It appeared as a fusiform elongated bacterium, without surface specialization, arranged in clusters and submerged in a rich biofilm matrix, which showed a well-developed micro-canalicular system. Our results provide the basis for the development of innovative strategies to quantify the effects of different treatments, in order to establish the best option to counteract ECC in pediatric patients.
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29
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Whitfield GB, Marmont LS, Bundalovic-Torma C, Razvi E, Roach EJ, Khursigara CM, Parkinson J, Howell PL. Discovery and characterization of a Gram-positive Pel polysaccharide biosynthetic gene cluster. PLoS Pathog 2020; 16:e1008281. [PMID: 32236137 PMCID: PMC7112168 DOI: 10.1371/journal.ppat.1008281] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 12/11/2019] [Indexed: 12/14/2022] Open
Abstract
Our understanding of the biofilm matrix components utilized by Gram-positive bacteria, and the signalling pathways that regulate their production are largely unknown. In a companion study, we developed a computational pipeline for the unbiased identification of homologous bacterial operons and applied this algorithm to the analysis of synthase-dependent exopolysaccharide biosynthetic systems. Here, we explore the finding that many species of Gram-positive bacteria have operons with similarity to the Pseudomonas aeruginosa pel locus. Our characterization of the pelDEADAFG operon from Bacillus cereus ATCC 10987, presented herein, demonstrates that this locus is required for biofilm formation and produces a polysaccharide structurally similar to Pel. We show that the degenerate GGDEF domain of the B. cereus PelD ortholog binds cyclic-3',5'-dimeric guanosine monophosphate (c-di-GMP), and that this binding is required for biofilm formation. Finally, we identify a diguanylate cyclase, CdgF, and a c-di-GMP phosphodiesterase, CdgE, that reciprocally regulate the production of Pel. The discovery of this novel c-di-GMP regulatory circuit significantly contributes to our limited understanding of c-di-GMP signalling in Gram-positive organisms. Furthermore, conservation of the core pelDEADAFG locus amongst many species of bacilli, clostridia, streptococci, and actinobacteria suggests that Pel may be a common biofilm matrix component in many Gram-positive bacteria.
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Affiliation(s)
- Gregory B Whitfield
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Lindsey S Marmont
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Cedoljub Bundalovic-Torma
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Erum Razvi
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Elyse J Roach
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Cezar M Khursigara
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - John Parkinson
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - P Lynne Howell
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
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30
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Mohammed M, Mekala LP, Chintalapati S, Chintalapati VR. New insights into aniline toxicity: Aniline exposure triggers envelope stress and extracellular polymeric substance formation in Rubrivivax benzoatilyticus JA2. JOURNAL OF HAZARDOUS MATERIALS 2020; 385:121571. [PMID: 31753663 DOI: 10.1016/j.jhazmat.2019.121571] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 09/12/2019] [Accepted: 10/29/2019] [Indexed: 05/16/2023]
Abstract
Aniline is a major environmental pollutant of serious concern due to its toxicity. Although microbial metabolism of aniline is well-studied, its toxic effects and physiological responses of microorganisms to aniline are largely unexplored. Rubrivivax benzoatilyticus JA2, an aniline non-degrading bacterium, tolerates high concentrations of aniline and produces extracellular polymeric substance(EPS). Surprisingly, strain JA2 forms EPS only when exposed to aniline and other toxic compounds like organic solvents and heavy metals indicating that EPS formation is coupled to cell toxicity. Further, extensive reanalysis of the previous proteomic data of aniline exposed cells revealed up-regulation of envelope stress response(ESR) proteins such as periplasmic protein folding, envelope integrity, transmembrane complex, and cell-wall remodelling proteins. In silico analysis and molecular modeling of three highly up-regulated proteins revealed that these proteins were homologous to CpxARP proteins of ESR signalling pathway. Furthermore, EPS formation to known ESR activators(Triton-X-100, EDTA) suggests that envelope stress possibly regulating the EPS production. The present study suggests that aniline triggers envelope stress; to counter this strain JA2 activates ESR pathway and EPS production. Our study revealed the hitherto unknown toxic effects of aniline as an acute envelope stressor thus toxicity of aniline may be more profound to life-forms than previously thought.
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Affiliation(s)
- Mujahid Mohammed
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, P.O. Central University, Hyderabad 500 046, India
| | - Lakshmi Prasuna Mekala
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, P.O. Central University, Hyderabad 500 046, India
| | - Sasikala Chintalapati
- Bacterial Discovery Laboratory, Center for Environment, IST, JNT University Hyderabad, Kukatpally, Hyderabad 500 085, India
| | - Venkata Ramana Chintalapati
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, P.O. Central University, Hyderabad 500 046, India.
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Kıvanç SA, Arık G, Akova-Budak B, Kıvanç M. Biofilm forming capacity and antibiotic susceptibility of Staphylococcus spp. with the icaA/icaD/bap genotype isolated from ocular surface of patients with diabetes. Malawi Med J 2019; 30:243-249. [PMID: 31798802 PMCID: PMC6863420 DOI: 10.4314/mmj.v30i4.6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Introduction Bacterial biofilm is an exopolysaccharide matrix that is produced by bacteria while they adhere on abiotic or biotic surfaces. The bacteria living in this matrix are more resistant to antibiotics than planctonic bacteria. The biofilm formation property of the bacteria is determined by genes; and this is related to virulence of the microorganism. In ophthalmology, biofilms form especially on abiotic surfaces such as silicon tubes, contact lenses, intraocular lenses etc. Aim Our aim was to investigate genotypic and phenotypic structures of biofilms that are produced by Staphylococcus spp., which was obtained from the eyes of diabetic patients and determine the effect on antibiotic susceptibility. Methods The study group was comprised with 83 isolates from diabetic patients and 21 isolates from non-diabetic patients. Presumptive isolates were detected and confirmed by a microbial identification system VITEK II. Automated EcoRI Ribotyping was performed. Biofilm production was detected by Congo Red Agar Plate and Microtiter Plate Assay. Disc diffusion method was used for determination of antibiotic susceptibility of isolates. Results Out of the 83 isolates from diabetic patients, 25 were weakly (30%), 20 were moderately (24%), and 25 were strongly (30%) biofilm positive. Seven isolates of S. aureus, 11 isolates of S.epidermidis, 2 isolates of S. warneri, 3 isolates of S.hominis, and 2 isolates of S.lugdunensis were identified as strong biofilm producers. Out of the 83 Staphylococcus isolates, 37 were cefuroxime, 18 ciprofloxacin, 11 vancomycin, 12 gatifloxacin, and 18 moxifloxacin resistant. In total, 37 strains were resistant to three or more antibiotics. There was a statistically significant relation between biofilm formation and multidrug resistance (against three or more antibiotics, p<0.001). In nondiabetic patients, 15(71%) isolates were non adherent or weakly adherent, and 2(10%) were strongly adherent biofilm positive. Conclusion In conclusion, bacterial conjunctival flora of patients with diabetes is likely to produce biofilm. Biofilm formation is associated with multidrug rsistance in patients with diabetes.
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Affiliation(s)
- Sertaç Argun Kıvanç
- Uludag University, School of Medicine, Department of Ophthalmology, Görükle, Bursa/Turkey
| | - Gizem Arık
- Anadolu University, Faculty of Science, Department of Microbiology, Eskişehir/Turkey
| | - Berna Akova-Budak
- Uludag University, School of Medicine, Department of Ophthalmology, Görükle, Bursa/Turkey
| | - Merih Kıvanç
- Anadolu University, Faculty of Science, Department of Microbiology, Eskişehir/Turkey
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32
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Bisht K, Wakeman CA. Discovery and Therapeutic Targeting of Differentiated Biofilm Subpopulations. Front Microbiol 2019; 10:1908. [PMID: 31507548 PMCID: PMC6718512 DOI: 10.3389/fmicb.2019.01908] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Accepted: 08/05/2019] [Indexed: 12/21/2022] Open
Abstract
The association of microorganisms into biofilms produces functionally organized microbial structures that promote community survival in a wide range of environments. Much like when individual cells within a multicellular organism express different genes from the same DNA blueprint, individual microbial cells located within different regions of a biofilm structure can exhibit distinct genetic programs. These spatially defined regions of physiologically differentiated cells are reminiscent of the role of tissues in multicellular organisms, with specific subpopulations in the microbial community serving defined roles to promote the overall health of the biofilm. The functions of these subpopulations are quite diverse and can range from dormant cells that can withstand antibiotic onslaughts to cells actively producing extracellular polymeric substances providing integrity to the entire community. The purpose of this review is to discuss the diverse roles of subpopulations in the stability and function of clonal biofilms, the methods for studying these subpopulations, and the ways these subpopulations can potentially be exploited for therapeutic intervention.
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Affiliation(s)
- Karishma Bisht
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, United States
| | - Catherine Ann Wakeman
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, United States
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Caldwell D, Iyer-Pascuzzi AS. A Scanning Electron Microscopy Technique for Viewing Plant-Microbe Interactions at Tissue and Cell-Type Resolution. PHYTOPATHOLOGY 2019; 109:1302-1311. [PMID: 30694115 DOI: 10.1094/phyto-07-18-0216-r] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Observing pathogen colonization and localization within specific plant tissues is a critical component of plant pathology research. High-resolution imaging, in which the researcher can clearly view the plant pathogen interacting with a specific plant cell, is needed to enhance our understanding of pathogen lifestyle and virulence mechanisms. However, it can be challenging to find the pathogen along the plant surface or in a specific cell type. Because of the time-consuming and expensive nature of high-resolution microscopy, techniques that allow a researcher to find a region of pathogen colonization more quickly at low resolution and subsequently move to a high-resolution microscope for detailed observation are needed. Here we present paraffin scanning electron microscopy (PSEM), a technique in which paraffin-embedded samples are first sectioned to identify a region of interest. Subsequently the same block is recut, deparaffinized, and used in scanning electron microscopy (SEM) to generate high-resolution images of plant-pathogen interactions in specific plant cell types. This method has several additional advantages over traditional SEM techniques, including reduced noise and better image quality. Here we use this technique to show that Fusarium oxysporum f. sp. lycopersici colonization is restricted in resistant Solanum pimpinellifolium and that PSEM works well in additional pathosystems, including maize leaves and Clavibacter michiganensis subsp. nebraskensis and Arabidopsis leaves and Pseudomonas syringae.
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Affiliation(s)
- Denise Caldwell
- Department of Botany and Plant Pathology, Center for Plant Biology, Purdue University, West Lafayette, IN 47907
| | - Anjali S Iyer-Pascuzzi
- Department of Botany and Plant Pathology, Center for Plant Biology, Purdue University, West Lafayette, IN 47907
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34
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Novikov I, Subbot A, Turenok A, Mayanskiy N, Chebotar I. A rapid method of whole cell sample preparation for scanning electron microscopy using neodymium chloride. Micron 2019; 124:102687. [PMID: 31302532 DOI: 10.1016/j.micron.2019.102687] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 05/26/2019] [Accepted: 05/26/2019] [Indexed: 10/26/2022]
Abstract
The quality of electron microscopy (EM) visualization of biological objects is constantly improving, primarily with the usage of more complex technologies, such as serial block-face scanning electron microscopy (SEM), focused ion beam scanning electron microscopy, and array tomography. Here we suggest a new rapid method of whole cell sample preparation for scanning EM using neodymium chloride treatment followed by staining with lead acetate. This variant of sample preparation does not require separate fixation, complete dehydration, and metal sputtering. By means of SEM in the back-scattered electron mode, in the neodymium-treated preparations, we visualized various morphological structures in human cells (nuclei with nucleoli, cytoskeleton, mitochondria) and microbial cells (Staphylococcus epidermidis, Streptococcus pneumoniae, Escherichia coli, and Candida albicans) preserving their species-specific shape and size. Thus, the suggested method provides additional information combining capabilities of SEM in visualizing cellular surface and transmission EM in detecting intracellular structures. Moreover, biological sample preparation with neodymium and lead is fast, informative, and cost-saving indicating a potential for its practical use for environmental SEM, and can be effectively combined with optical microscopy.
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Affiliation(s)
- Ivan Novikov
- Research Institute of Eye Diseases, 11 Rossolimo Street, 119021, Moscow, Russia
| | - Anastasia Subbot
- Research Institute of Eye Diseases, 11 Rossolimo Street, 119021, Moscow, Russia
| | - Andrey Turenok
- National Scientific and Practical Center of Children's Health, 2 Lomonosovsky Avenue, 119991, Moscow, Russia
| | - Nikolay Mayanskiy
- National Scientific and Practical Center of Children's Health, 2 Lomonosovsky Avenue, 119991, Moscow, Russia; Pirogov Russian National Research Medical University, 1 Ostrovityanova Street, 117997, Moscow, Russia
| | - Igor Chebotar
- Central Research Institute of Epidemiology, 3A Novogireevskay Street, 111123, Moscow, Russia.
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35
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In-Situ High Resolution Dynamic X-ray Microtomographic Imaging of Olive Oil Removal in Kitchen Sponges by Squeezing and Rinsing. MATERIALS 2018; 11:ma11081482. [PMID: 30127273 PMCID: PMC6119885 DOI: 10.3390/ma11081482] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 08/17/2018] [Accepted: 08/17/2018] [Indexed: 01/24/2023]
Abstract
Recent advances in high resolution X-ray tomography (μCT) technology have enabled in-situ dynamic μCT imaging (4D-μCT) of time-dependent processes inside 3D structures, non-destructively and non-invasively. This paper illustrates the application of 4D-μCT for visualizing the removal of fatty liquids from kitchen sponges made of polyurethane after rinsing (absorption), squeezing (desorption) and cleaning (adding detergents). For the first time, time-dependent imaging of this type of system was established with sufficiently large contrast gradient between water (with/without detergent) and olive oil (model fat) by the application of suitable fat-sensitive X-ray contrast agents. Thus, contrasted olive oil filled sponges were rinsed and squeezed in a unique laboratory loading device with a fluid flow channel designed to fit inside a rotating gantry-based X-ray μCT system. Results suggest the use of brominated vegetable oil as a preferred contrast agent over magnetite powder for enhancing the attenuation coefficient of olive oil in a multi fluid filled kitchen sponge. The contrast agent (brominated vegetable oil) and olive oil were mixed and subsequently added on to the sponge. There was no disintegration seen in the mixture of contrast agent and olive oil during the cleaning process by detergents. The application of contrast agents also helped in accurately tracking the movement and volume changes of soils in compressed open cell structures. With the in house-built cleaning device, it was quantified that almost 99% of cleaning was possible for contrasted olive oil (brominated vegetable oil with olive oil) dispersed in the sponge. This novel approach allowed for realistic mimicking of the cleaning process and provided closer evaluation of the effectiveness of cleaning by detergents to minimize bacterial growth.
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Clinical Significance of Biofilm on Silicone Tubes Removed From Patients With Nasolacrimal Duct Stenosis. J Craniofac Surg 2018; 29:462-465. [PMID: 29194257 DOI: 10.1097/scs.0000000000004191] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
PURPOSE To determine the relationship between the optical density of biofilms on silicone tubes and surgical outcomes. METHODS A total of 43 silicone tubes from 33 patients with nasolacrimal duct stenosis were enrolled at 6 months after bicanalicular silicone tube intubation. The removed silicone tubes were divided into 2 segments. One segment of silicone tube was cultured while the other segment was used to measure optical density of biofilm. Each segment was divided into 3 pieces according to average normal human nasolacrimal anatomy. The first piece was located from puncta to lacrimal sac. The second piece was inside the nasolacrimal duct. The third piece was in the nasal cavity. Surgical outcome was evaluated at postoperative 12 months based on Munk score and fluorescein dye disappearance test. RESULTS A total of 31 (72.1%) patients were surgically successful while 12 (27.9%) patients had surgical failure with persistent epiphora. In the second piece of silicone tube, the mean optical density of biofilm was 0.2654 nm in the surgical success group and 0.4472 nm in the surgical failure group. These results showed statistically significant (P < 0.01) difference. The most frequently isolated organism was Staphylococcus aureus in the surgical success group (7 of 31 patients, 22.6%). It was Pseudomonas aeruginosa in the surgical failure group (6 of 12 patients, 50%). CONCLUSION This is the first study that determines the relationship between biofilm on silicone tube and surgical outcome. Biofilm formed on silicone tubes in nasolacrimal duct might cause surgical failure.
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Magana M, Sereti C, Ioannidis A, Mitchell CA, Ball AR, Magiorkinis E, Chatzipanagiotou S, Hamblin MR, Hadjifrangiskou M, Tegos GP. Options and Limitations in Clinical Investigation of Bacterial Biofilms. Clin Microbiol Rev 2018; 31:e00084-16. [PMID: 29618576 PMCID: PMC6056845 DOI: 10.1128/cmr.00084-16] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Bacteria can form single- and multispecies biofilms exhibiting diverse features based upon the microbial composition of their community and microenvironment. The study of bacterial biofilm development has received great interest in the past 20 years and is motivated by the elegant complexity characteristic of these multicellular communities and their role in infectious diseases. Biofilms can thrive on virtually any surface and can be beneficial or detrimental based upon the community's interplay and the surface. Advances in the understanding of structural and functional variations and the roles that biofilms play in disease and host-pathogen interactions have been addressed through comprehensive literature searches. In this review article, a synopsis of the methodological landscape of biofilm analysis is provided, including an evaluation of the current trends in methodological research. We deem this worthwhile because a keyword-oriented bibliographical search reveals that less than 5% of the biofilm literature is devoted to methodology. In this report, we (i) summarize current methodologies for biofilm characterization, monitoring, and quantification; (ii) discuss advances in the discovery of effective imaging and sensing tools and modalities; (iii) provide an overview of tailored animal models that assess features of biofilm infections; and (iv) make recommendations defining the most appropriate methodological tools for clinical settings.
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Affiliation(s)
- Maria Magana
- Department of Clinical Microbiology, Athens Medical School, Aeginition Hospital, Athens, Greece
| | - Christina Sereti
- Department of Clinical Microbiology, Athens Medical School, Aeginition Hospital, Athens, Greece
- Department of Microbiology, Thriassio General Hospital, Attiki, Greece
| | - Anastasios Ioannidis
- Department of Clinical Microbiology, Athens Medical School, Aeginition Hospital, Athens, Greece
- Department of Nursing, Faculty of Human Movement and Quality of Life Sciences, University of Peloponnese, Sparta, Greece
| | - Courtney A Mitchell
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee, USA
| | - Anthony R Ball
- Gliese 623b, Mendon, Massachusetts, USA
- GAMA Therapeutics LLC, Pepperell, Massachusetts, USA
| | - Emmanouil Magiorkinis
- Department of Hygiene, Epidemiology and Medical Statistics, Medical School, University of Athens, Athens-Goudi, Greece
| | | | - Michael R Hamblin
- Harvard-MIT Division of Health Science and Technology, Cambridge, Massachusetts, USA
- Department of Dermatology, Harvard Medical School, Boston, Massachusetts, USA
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Maria Hadjifrangiskou
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - George P Tegos
- Gliese 623b, Mendon, Massachusetts, USA
- GAMA Therapeutics LLC, Pepperell, Massachusetts, USA
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Immobilization of Planococcus sp. S5 Strain on the Loofah Sponge and Its Application in Naproxen Removal. Catalysts 2018. [DOI: 10.3390/catal8050176] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Planococcus sp. S5, a Gram-positive bacterium isolated from the activated sludge is known to degrade naproxen in the presence of an additional carbon source. Due to the possible toxicity of naproxen and intermediates of its degradation, the whole cells of S5 strain were immobilized onto loofah sponge. The immobilized cells degraded 6, 9, 12 or 15 mg/L of naproxen faster than the free cells. Planococcus sp. cells immobilized onto the loofah sponge were able to degrade naproxen efficiently for 55 days without significant damage and disintegration of the carrier. Analysis of the activity of enzymes involved in naproxen degradation showed that stabilization of S5 cells in exopolysaccharide (EPS) resulted in a significant increase of their activity. Changes in the structure of biofilm formed on the loofah sponge cubes during degradation of naproxen were observed. Developed biocatalyst system showed high resistance to naproxen and its intermediates and degraded higher concentrations of the drug in comparison to the free cells.
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Cornell WC, Morgan CJ, Koyama L, Sakhtah H, Mansfield JH, Dietrich LEP. Paraffin Embedding and Thin Sectioning of Microbial Colony Biofilms for Microscopic Analysis. J Vis Exp 2018:57196. [PMID: 29630036 PMCID: PMC5933251 DOI: 10.3791/57196] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Sectioning via paraffin embedding is a broadly established technique in eukaryotic systems. Here we provide a method for the fixation, embedding, and sectioning of intact microbial colony biofilms using perfused paraffin wax. To adapt this method for use on colony biofilms, we developed techniques for maintaining each sample on its growth substrate and laminating it with an agar overlayer, and added lysine to the fixative solution. These optimizations improve sample retention and preservation of micromorphological features. Samples prepared in this manner are amenable to thin sectioning and imaging by light, fluorescence, and transmission electron microscopy. We have applied this technique to colony biofilms of Pseudomonas aeruginosa, Pseudomonas synxantha, Bacillus subtilis, and Vibrio cholerae. The high level of detail visible in samples generated by this method, combined with reporter strain engineering or the use of specific dyes, can provide exciting insights into the physiology and development of microbial communities.
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Affiliation(s)
| | | | - Leslie Koyama
- Department of Biological Sciences, Columbia University; Department of Biology, Barnard College, Columbia University
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Morrow CP, McGaughey AL, Hiibel SR, Childress AE. Submerged or sidestream? The influence of module configuration on fouling and salinity in osmotic membrane bioreactors. J Memb Sci 2018. [DOI: 10.1016/j.memsci.2017.11.030] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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El Haj C, Murillo O, Ribera A, Lloberas N, Gómez-Junyent J, Tubau F, Fontova P, Cabellos C, Ariza J. Evaluation of linezolid or trimethoprim/sulfamethoxazole in combination with rifampicin as alternative oral treatments based on an in vitro pharmacodynamic model of staphylococcal biofilm. Int J Antimicrob Agents 2018; 51:854-861. [PMID: 29374577 DOI: 10.1016/j.ijantimicag.2018.01.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 01/18/2018] [Indexed: 11/30/2022]
Abstract
Combinations of linezolid (LZD) or trimethoprim/sulfamethoxazole (SXT) plus rifampicin (RIF) are alternative oral treatments for staphylococcal prosthetic joint infections (PJIs) when fluoroquinolones are not possible to use, but there is limited evidence regarding their activity. This study evaluated the efficacy of LZD and SXT, alone and in combination with RIF, against Staphylococcus aureus in an in vitro pharmacokinetic/pharmacodynamic biofilm model. Using the CDC Biofilm Reactor® system, simulated regimens of LZD (600 mg every 12 h), SXT (160/800 mg every 8 h) and levofloxacin (LVX) (750 mg/day), alone and in combination with RIF (600 mg/day), were evaluated against one methicillin-susceptible S. aureus (MSSA) and one methicillin-resistant S. aureus (MRSA) strain. Antibiotic efficacy was evaluated by the decrease in planktonic bacterial counts from medium and biofilm-embedded bacteria from coupons over 56 h. Resistant strains were screened. In both strains, SXT alone was ineffective and LZD presented low activity, but no resistance emerged. Combinations with RIF significantly increased the antibiofilm efficacy against MSSA (Δlog CFU/mL 56h-0h: SXT + RIF, -2.9 and LZD + RIF, -3.1), but RIF-resistant strains appeared with SXT + RIF. Against MRSA, LZD + RIF (-3.1) protected against the emergence of resistance and was more effective than SXT + RIF (-0.6; P <0.05), in which RIF-resistant strains were again detected. LVX + RIF confirmed its high efficacy against biofilm-embedded bacteria, this being the most effective therapy (-5.1 against MSSA). The emergence of RIF-resistant strains with SXT + RIF poses serious concerns for its use in clinical practice. Interestingly, LZD + RIF appears to be an appropriate alternative for PJI caused by LVX-resistant S. aureus.
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Affiliation(s)
- Cristina El Haj
- Laboratory of Experimental Infection, Infectious Diseases Service, IDIBELL-Hospital Universitari Bellvitge, University of Barcelona, Feixa Llarga, s/n, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Oscar Murillo
- Laboratory of Experimental Infection, Infectious Diseases Service, IDIBELL-Hospital Universitari Bellvitge, University of Barcelona, Feixa Llarga, s/n, 08907, L'Hospitalet de Llobregat, Barcelona, Spain; Spanish Network for the Research in Infectious Diseases (REIPIRD12/0015), Instituto de Salud Carlos III, Madrid, Spain.
| | - Alba Ribera
- Laboratory of Experimental Infection, Infectious Diseases Service, IDIBELL-Hospital Universitari Bellvitge, University of Barcelona, Feixa Llarga, s/n, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Nuria Lloberas
- Nephrology Service and Laboratory of Experimental Nephrology, University of Barcelona, Campus Bellvitge, Pavelló de Govern, Feixa Llarga, s/n, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Joan Gómez-Junyent
- Laboratory of Experimental Infection, Infectious Diseases Service, IDIBELL-Hospital Universitari Bellvitge, University of Barcelona, Feixa Llarga, s/n, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Fe Tubau
- Department of Microbiology, IDIBELL-Hospital Universitari Bellvitge, Barcelona, Spain; Department of Microbiology, CIBERES ISCIII, Madrid, Spain
| | - Pere Fontova
- Nephrology Service and Laboratory of Experimental Nephrology, University of Barcelona, Campus Bellvitge, Pavelló de Govern, Feixa Llarga, s/n, 08907, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Carme Cabellos
- Laboratory of Experimental Infection, Infectious Diseases Service, IDIBELL-Hospital Universitari Bellvitge, University of Barcelona, Feixa Llarga, s/n, 08907, L'Hospitalet de Llobregat, Barcelona, Spain; Spanish Network for the Research in Infectious Diseases (REIPIRD12/0015), Instituto de Salud Carlos III, Madrid, Spain
| | - Javier Ariza
- Laboratory of Experimental Infection, Infectious Diseases Service, IDIBELL-Hospital Universitari Bellvitge, University of Barcelona, Feixa Llarga, s/n, 08907, L'Hospitalet de Llobregat, Barcelona, Spain; Spanish Network for the Research in Infectious Diseases (REIPIRD12/0015), Instituto de Salud Carlos III, Madrid, Spain
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Methods for Collection and Characterization of Samples From Icy Environments. METHODS IN MICROBIOLOGY 2018. [DOI: 10.1016/bs.mim.2018.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Wille G, Hellal J, Ollivier P, Richard A, Burel A, Jolly L, Crampon M, Michel C. Cryo-Scanning Electron Microscopy (SEM) and Scanning Transmission Electron Microscopy (STEM)-in-SEM for Bio- and Organo-Mineral Interface Characterization in the Environment. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2017; 23:1159-1172. [PMID: 29143694 DOI: 10.1017/s143192761701265x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Understanding biofilm interactions with surrounding substratum and pollutants/particles can benefit from the application of existing microscopy tools. Using the example of biofilm interactions with zero-valent iron nanoparticles (nZVI), this study aims to apply various approaches in biofilm preparation and labeling for fluorescent or electron microscopy and energy dispersive X-ray spectrometry (EDS) microanalysis for accurate observations. According to the targeted microscopy method, biofilms were sampled as flocs or attached biofilm, submitted to labeling using 4',6-diamidino-2-phenylindol, lectins PNA and ConA coupled to fluorescent dye or gold nanoparticles, and prepared for observation (fixation, cross-section, freezing, ultramicrotomy). Fluorescent microscopy revealed that nZVI were embedded in the biofilm structure as aggregates but the resolution was insufficient to observe individual nZVI. Cryo-scanning electron microscopy (SEM) observations showed nZVI aggregates close to bacteria, but it was not possible to confirm direct interactions between nZVI and cell membranes. Scanning transmission electron microscopy in the SEM (STEM-in-SEM) showed that nZVI aggregates could enter the biofilm to a depth of 7-11 µm. Bacteria were surrounded by a ring of extracellular polymeric substances (EPS) preventing direct nZVI/membrane interactions. STEM/EDS mapping revealed a co-localization of nZVI aggregates with lectins suggesting a potential role of EPS in nZVI embedding. Thus, the combination of divergent microscopy approaches is a good approach to better understand and characterize biofilm/metal interactions.
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Affiliation(s)
- Guillaume Wille
- 1BRGM,3 avenue Claude Guillemin,BP 36009,45060 Orleans Cedex 2,France
| | - Jennifer Hellal
- 1BRGM,3 avenue Claude Guillemin,BP 36009,45060 Orleans Cedex 2,France
| | - Patrick Ollivier
- 1BRGM,3 avenue Claude Guillemin,BP 36009,45060 Orleans Cedex 2,France
| | - Annie Richard
- 2CME,University of Orleans,1 Rue de Chartres,BP 6759,45067 Orleans Cedex 2,France
| | - Agnes Burel
- 3MRIC TEM BIOSIT,University of Rennes,1-2 avenue du Pr Léon Bernard,CS 34317,35043 Rennes Cedex,France
| | - Louis Jolly
- 1BRGM,3 avenue Claude Guillemin,BP 36009,45060 Orleans Cedex 2,France
| | - Marc Crampon
- 1BRGM,3 avenue Claude Guillemin,BP 36009,45060 Orleans Cedex 2,France
| | - Caroline Michel
- 1BRGM,3 avenue Claude Guillemin,BP 36009,45060 Orleans Cedex 2,France
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Dutta Sinha S, Das S, Tarafdar S, Dutta T. Monitoring of Wild Pseudomonas Biofilm Strain Conditions Using Statistical Characterization of Scanning Electron Microscopy Images. Ind Eng Chem Res 2017. [DOI: 10.1021/acs.iecr.7b01106] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Suparna Dutta Sinha
- Condensed Matter Physics Research Centre, Department of Physics, Jadavpur University, Kolkata−700032, India
| | - Saptarshi Das
- Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, U.K
- Department of Power
Engineering, Jadavpur University, Salt Lake Campus, LB-8, Sector 3, Kolkata−700098, India
| | - Sujata Tarafdar
- Condensed Matter Physics Research Centre, Department of Physics, Jadavpur University, Kolkata−700032, India
| | - Tapati Dutta
- Physics Department, St. Xavier’s College, Kolkata−700016, India
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de Almeida FP, Freire DMG, Lins U, Gutarra MLE. Surface imaging of the filamentous fungus Penicillium simplicissimum growing in a solid-state fermentation system. Micron 2017; 99:19-25. [DOI: 10.1016/j.micron.2017.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 02/21/2017] [Accepted: 04/03/2017] [Indexed: 11/24/2022]
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Dickerson MB, Dennis PB, Tondiglia VP, Nadeau LJ, Singh KM, Drummy LF, Partlow BP, Brown DP, Omenetto FG, Kaplan DL, Naik RR. 3D Printing of Regenerated Silk Fibroin and Antibody-Containing Microstructures via Multiphoton Lithography. ACS Biomater Sci Eng 2017; 3:2064-2075. [DOI: 10.1021/acsbiomaterials.7b00338] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Matthew B. Dickerson
- Materials
and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson
AFB, Ohio 45433, United States
| | - Patrick B. Dennis
- Materials
and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson
AFB, Ohio 45433, United States
| | - Vincent P. Tondiglia
- Materials
and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson
AFB, Ohio 45433, United States
| | - Lloyd J. Nadeau
- Materials
and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson
AFB, Ohio 45433, United States
| | - Kristi M. Singh
- Materials
and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson
AFB, Ohio 45433, United States
| | - Lawrence F. Drummy
- Materials
and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson
AFB, Ohio 45433, United States
| | - Benjamin P. Partlow
- Biomedical
Engineering Department, Tufts University, Medford, Massachusetts 02155, United States
| | - Dean P. Brown
- Materials
and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson
AFB, Ohio 45433, United States
| | - Fiorenzo G. Omenetto
- Biomedical
Engineering Department, Tufts University, Medford, Massachusetts 02155, United States
| | - David L. Kaplan
- Biomedical
Engineering Department, Tufts University, Medford, Massachusetts 02155, United States
| | - Rajesh R. Naik
- 711th Human Performance Wing, Air Force Research Laboratory, Wright-Patterson
AFB, Ohio 45433, United States
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Risk of Fungal Infection to Dental Patients. ScientificWorldJournal 2017; 2017:2982478. [PMID: 28695189 PMCID: PMC5488164 DOI: 10.1155/2017/2982478] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 05/09/2017] [Accepted: 05/21/2017] [Indexed: 01/12/2023] Open
Abstract
Fungi can cause various diseases, and some pathogenic fungi have been detected in the water of dental equipment. This environment offers suitable conditions for fungal biofilms to emerge, which can facilitate mycological contamination. This study verified whether the water employed in the dental units of two dental clinics at the University of Franca was contaminated with fungi. This study also evaluated the ability of the detected fungi to form biofilms. The high-revving engine contained the largest average amount of fungi, 14.93 ± 18.18 CFU/mL. The main fungal species verified in this equipment belonged to the genera Aspergillus spp., Fusarium spp., Candida spp., and Rhodotorula spp. Among the isolated filamentous fungi, only one fungus of the genus Fusarium spp. did not form biofilms. As for yeasts, all the Candida spp. isolates grew as biofilm, but none of the Rhodotorula spp. isolates demonstrated this ability. Given that professionals and patients are often exposed to water and aerosols generated by the dental procedure, the several fungal species detected herein represent a potential risk especially to immunocompromised patients undergoing dental treatment. Therefore, frequent microbiological monitoring of the water employed in dental equipment is crucial to reduce the presence of contaminants.
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Logroño W, Pérez M, Urquizo G, Kadier A, Echeverría M, Recalde C, Rákhely G. Single chamber microbial fuel cell (SCMFC) with a cathodic microalgal biofilm: A preliminary assessment of the generation of bioelectricity and biodegradation of real dye textile wastewater. CHEMOSPHERE 2017; 176:378-388. [PMID: 28278426 DOI: 10.1016/j.chemosphere.2017.02.099] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Revised: 02/15/2017] [Accepted: 02/19/2017] [Indexed: 06/06/2023]
Abstract
An air exposed single-chamber microbial fuel cell (SCMFC) using microalgal biocathodes was designed. The reactors were tested for the simultaneous biodegradation of real dye textile wastewater (RTW) and the generation of bioelectricity. The results of digital image processing revealed a maximum coverage area on the biocathodes by microalgal cells of 42%. The atmospheric and diffused CO2 could enable good algal growth and its immobilized operation on the cathode electrode. The biocathode-SCMFCs outperformed an open circuit voltage (OCV), which was 18%-43% higher than the control. Furthermore, the maximum volumetric power density achieved was 123.2 ± 27.5 mW m-3. The system was suitable for the treatment of RTW and the removal/decrease of COD, colour and heavy metals. High removal efficiencies were observed in the SCMFCs for Zn (98%) and COD (92-98%), but the removal efficiencies were considerably lower for Cr (54-80%). We observed that this single chamber MFC simplifies a double chamber system. The bioelectrochemical performance was relatively low, but the treatment capacity of the system seems encouraging in contrast to previous studies. A proof-of-concept experiment demonstrated that the microalgal biocathode could operate in air exposed conditions, seems to be a promising alternative to a Pt cathode and is an efficient and cost-effective approach to improve the performance of single chamber MFCs.
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Affiliation(s)
- Washington Logroño
- Centro de Investigación de Energías Alternativas y Ambiente, Escuela Superior Politécnica de Chimborazo, Chimborazo, EC060155, Ecuador; Department of Biotechnology, University of Szeged, H-6726, Szeged, Hungary.
| | - Mario Pérez
- Centro de Investigación de Energías Alternativas y Ambiente, Escuela Superior Politécnica de Chimborazo, Chimborazo, EC060155, Ecuador
| | - Gladys Urquizo
- Centro de Investigación de Energías Alternativas y Ambiente, Escuela Superior Politécnica de Chimborazo, Chimborazo, EC060155, Ecuador
| | - Abudukeremu Kadier
- Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, National University of Malaysia (UKM), 43600, UKM Bangi, Selangor, Malaysia
| | - Magdy Echeverría
- Centro de Investigación de Energías Alternativas y Ambiente, Escuela Superior Politécnica de Chimborazo, Chimborazo, EC060155, Ecuador
| | - Celso Recalde
- Centro de Investigación de Energías Alternativas y Ambiente, Escuela Superior Politécnica de Chimborazo, Chimborazo, EC060155, Ecuador; Instituto de Ciencia, Innovación, Tecnología y Saberes, Universidad Nacional de Chimborazo, Riobamba, Ecuador
| | - Gábor Rákhely
- Department of Biotechnology, University of Szeged, H-6726, Szeged, Hungary; Institute of Biophysics, Biological Research Centre Hungarian Academy of Sciences, Szeged, Hungary
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Costa-Orlandi CB, Sardi JCO, Pitangui NS, de Oliveira HC, Scorzoni L, Galeane MC, Medina-Alarcón KP, Melo WCMA, Marcelino MY, Braz JD, Fusco-Almeida AM, Mendes-Giannini MJS. Fungal Biofilms and Polymicrobial Diseases. J Fungi (Basel) 2017; 3:jof3020022. [PMID: 29371540 PMCID: PMC5715925 DOI: 10.3390/jof3020022] [Citation(s) in RCA: 119] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 04/19/2017] [Accepted: 05/04/2017] [Indexed: 12/29/2022] Open
Abstract
Biofilm formation is an important virulence factor for pathogenic fungi. Both yeasts and filamentous fungi can adhere to biotic and abiotic surfaces, developing into highly organized communities that are resistant to antimicrobials and environmental conditions. In recent years, new genera of fungi have been correlated with biofilm formation. However, Candida biofilms remain the most widely studied from the morphological and molecular perspectives. Biofilms formed by yeast and filamentous fungi present differences, and studies of polymicrobial communities have become increasingly important. A key feature of resistance is the extracellular matrix, which covers and protects biofilm cells from the surrounding environment. Furthermore, to achieve cell–cell communication, microorganisms secrete quorum-sensing molecules that control their biological activities and behaviors and play a role in fungal resistance and pathogenicity. Several in vitro techniques have been developed to study fungal biofilms, from colorimetric methods to omics approaches that aim to identify new therapeutic strategies by developing new compounds to combat these microbial communities as well as new diagnostic tools to identify these complex formations in vivo. In this review, recent advances related to pathogenic fungal biofilms are addressed.
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Affiliation(s)
- Caroline B Costa-Orlandi
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Janaina C O Sardi
- Department of Physiological Sciences, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba SP 13414-018, Brazil.
| | - Nayla S Pitangui
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Haroldo C de Oliveira
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Liliana Scorzoni
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Mariana C Galeane
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Kaila P Medina-Alarcón
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Wanessa C M A Melo
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Mônica Y Marcelino
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Jaqueline D Braz
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Ana Marisa Fusco-Almeida
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
| | - Maria José S Mendes-Giannini
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara SP 14800-903, Brazil.
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Raab N, Bachelet I. Resolving biofilm topography by native scanning electron microscopy. J Biol Methods 2017; 4:e70. [PMID: 31453228 PMCID: PMC6706123 DOI: 10.14440/jbm.2017.173] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 02/06/2017] [Accepted: 02/27/2017] [Indexed: 01/01/2023] Open
Abstract
Scanning electron microscopy (SEM) is a powerful tool for structural analysis, but it requires biological samples to undergo lengthy, chemically-complex multi-step preparation procedures, arguably altering some features in the sample. Here we report an ultra-rapid and chemical-free technique for visualizing bacterial biofilms at their native state. Our technique minimizes the time interval from culture to imaging to approximately 20 min, while producing high-resolution images that enable the detection of a variety of topographic features such as bacterial chains, and resolving cells from matrix. We analyzed images obtained from Bacillus subtilis biofilms, demonstrate the usefulness of this technique for multiple types of image analysis, and discuss its potential to be improved and adapted to other types of biological samples.
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Affiliation(s)
- Neta Raab
- Augmanity, Rehovot, Israel.,Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
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