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Abu Quba AA, Goebel MO, Karagulyan M, Miltner A, Kästner M, Bachmann J, Schaumann GE, Diehl D. Hypertonic stress induced changes of Pseudomonas fluorescens adhesion towards soil minerals studied by AFM. Sci Rep 2023; 13:17146. [PMID: 37816775 PMCID: PMC10564757 DOI: 10.1038/s41598-023-44256-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 10/05/2023] [Indexed: 10/12/2023] Open
Abstract
Studying bacterial adhesion to mineral surfaces is crucial for understanding soil properties. Recent research suggests that minimal coverage of sand particles with cell fragments significantly reduces soil wettability. Using atomic force microscopy (AFM), we investigated the influence of hypertonic stress on Pseudomonas fluorescens adhesion to four different minerals in water. These findings were compared with theoretical XDLVO predictions. To make adhesion force measurements comparable for irregularly shaped particles, we normalized adhesion forces by the respective cell-mineral contact area. Our study revealed an inverse relationship between wettability and the surface-organic carbon content of the minerals. This relationship was evident in the increased adhesion of cells to minerals with decreasing wettability. This phenomenon was attributed to hydrophobic interactions, which appeared to be predominant in all cell-mineral interaction scenarios alongside with hydrogen bonding. Moreover, while montmorillonite and goethite exhibited stronger adhesion to stressed cells, presumably due to enhanced hydrophobic interactions, kaolinite showed an unexpected trend of weaker adhesion to stressed cells. Surprisingly, the adhesion of quartz remained independent of cell stress level. Discrepancies between measured cell-mineral interactions and those calculated by XDLVO, assuming an idealized sphere-plane geometry, helped us interpret the chemical heterogeneity arising from differently exposed edges and planes of minerals. Our results suggest that bacteria may have a significant impact on soil wettability under changing moisture condition.
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Affiliation(s)
- Abd Alaziz Abu Quba
- Institute for Environmental Sciences, University of Kaiserslautern-Landau (RPTU), Landau, Germany
| | - Marc-Oliver Goebel
- Institute of Soil Science, Leibniz Universität Hannover, Hannover, Germany
| | - Mariam Karagulyan
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Anja Miltner
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Matthias Kästner
- Department of Environmental Biotechnology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Jörg Bachmann
- Institute of Soil Science, Leibniz Universität Hannover, Hannover, Germany
| | - Gabriele E Schaumann
- Institute for Environmental Sciences, University of Kaiserslautern-Landau (RPTU), Landau, Germany
| | - Doerte Diehl
- Institute for Environmental Sciences, University of Kaiserslautern-Landau (RPTU), Landau, Germany.
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2
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Zdarta A, Kaczorek E. Nanomechanical changes in probiotic bacteria under antibiotics exposure: Implications on Lactobacillus biofilm formation. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2023; 1870:119533. [PMID: 37414100 DOI: 10.1016/j.bbamcr.2023.119533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 06/28/2023] [Accepted: 06/29/2023] [Indexed: 07/08/2023]
Abstract
Recognition of the microbial cell's surface constituents' biophysical properties is an important research topic, allowing a better understanding of the cell's behaviour under different conditions. Atomic force microscopy (AFM) was employed in this study to analyse the basis of the nanomechanical changes in probiotic bacteria under nitrofurantoin, furazolidone, and nitrofurazone exposure. Recorded significant changes in the two Lactobacillus strains cells morphology, topography, and adhesion parameters resulted in the increase of the cells' longitude (up to 2.58 μm), profile height (by around 0.50 μm), and decrease in the adhesion force (up to 13.58 nN). Young's modulus and adhesion energy decreased within 96 h, however with no negative effect on the cells' morphology or loss of structural integrity. Observed modifications present the mode of action of the 5-nitrofuran derivative antibiotics on probiotic biofilm formation and suggest activation of the multilevel adaptation mechanisms to counteract unfavorable environments. A visual change in bacterial morphology such as an increased surface-to-volume ratio might be a link between molecular-level events and outcomes in individual cells and biofilms. This paper for the first time shows, that these antibiotics affect the properties of non-target microorganisms as lactobacilli, and might impair biofilm formation. However, the degree of such transformations depends on the delivered active substance.
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Affiliation(s)
- Agata Zdarta
- Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland.
| | - Ewa Kaczorek
- Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
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3
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Volle C, Núñez ME, Spain EM, Hart BC, Wengen MB, Lane S, Criollo A, Mahoney CA, Ferguson MA. AFM Force Mapping Elucidates Pilus Deployment and Key Lifestyle-Dependent Surface Properties in Bdellovibrio bacteriovorus. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:4233-4244. [PMID: 36926913 PMCID: PMC10062353 DOI: 10.1021/acs.langmuir.2c03134] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 03/03/2023] [Indexed: 06/18/2023]
Abstract
Bdellovibrio bacteriovorus is known for predation of a wide variety of Gram-negative bacteria, making it of interest as an alternative or supplement to chemical antibiotics. However, a fraction of B. bacteriovorus follows a nonpredatory, "host-independent" (HI) life cycle. In this study, live predatory and HI B. bacteriovorus were captured on a surface and examined, in buffer, by collecting force maps using atomic force microscopy (AFM). The approach curves obtained on HI cells are similar to those on other Gram-negative cells, with a short nonlinear region followed by a linear region. In contrast, the approach curves obtained on predatory cells have a large nonlinear region, reflecting the unusual flexibility of the predatory cell. As the AFM tip is retracted, it shows virtually no adhesion to predatory B. bacteriovorus but has multiple adhesion events on HI cells and the 200-500+ nm region immediately surrounding them. Measured pull-off forces, pull-off distances, and effective spring constants are consistent with the multiple stretching events of Type IV pili, both on and especially adjacent to the cells. Exposure of the HI B. bacteriovorus to a pH-neutral 10% cranberry juice solution, which contains type A proanthocyanidins that are known to interfere with the adhesion of multiple types of pili, results in a substantial reduction in adhesion. Type IV pili are required for successful predation by B. bacteriovorus, but pili used in the predation process are located at the non-flagellated pole of the cell and can retract when not in use. Such pili are rarely observed under the conditions of this study, where the predator has not encountered a prey cell. In contrast, HI cells appear to have many pili distributed on and around the whole cell, presumably ready to be utilized for a variety of HI cell activities including attachment to surfaces.
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Affiliation(s)
- Catherine
B. Volle
- Departments
of Chemistry and Biology, Cornell College, Mount Vernon, Iowa 52314, United States
| | - Megan E. Núñez
- Department
of Chemistry, Wellesley College, Wellesley, Massachusetts 02481, United States
| | - Eileen M. Spain
- Department
of Chemistry, Occidental College, Los Angeles, California 90041, United States
| | - Bridget C. Hart
- Department
of Chemistry, State University of New York, New Paltz, New York 12561, United States
| | - Michael B. Wengen
- Department
of Chemistry, State University of New York, New Paltz, New York 12561, United States
| | - Sophia Lane
- Department
of Chemistry, State University of New York, New Paltz, New York 12561, United States
| | - Alexa Criollo
- Department
of Chemistry, State University of New York, New Paltz, New York 12561, United States
| | - Catherine A. Mahoney
- Department
of Chemistry, State University of New York, New Paltz, New York 12561, United States
| | - Megan A. Ferguson
- Department
of Chemistry, State University of New York, New Paltz, New York 12561, United States
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4
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Forces Governing the Transport of Pathogenic and Nonpathogenic Escherichia coli in Nitrogen and Magnesium Doped Biochar Amended Sand Columns. MICROBIOLOGY RESEARCH 2023. [DOI: 10.3390/microbiolres14010018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
Background: Access to safe drinking water remains a global issue with fecal indicator bacteria being major pollutants. Biochars offer low-cost adsorbents for bacterial pathogens. A fundamental understanding of how biochars interact with bacterial pathogens is essential to designing effective biofilters. Methods: Water-saturated sand columns amended with Magnesium and Nitrogen-doped biochars produced by pyrolysis at 400, 500, 600, and 700 °C were used to Quantify the transport of pathogenic Escherichia coli O157:H7 and nonpathogenic E. coli k12 strains in porous media. Measured data were modeled using DLVO theory of colloidal stability. were explored. Results: (1) Biochar is hydrophobic while sand and bacteria are hydrophilic; (2) all Gibbs free energy values quantified between E. coli O157:H7 and biochar were negative except for biochar produced at 700 °C; (3) all types of forces investigated (van der Waals, electrostatic, and acid-base interactions) played a role in governing the interactions between bacteria and biochar. Conclusions: (1) Adding doped biochar to sand at a 2% weight ratio enhanced the retention of bacterial cells in the sand/biochar columns; (2) bacterial transport is strain-dependent and mediated by various types of forces resulting from interactions between the various functional groups displayed on bacteria and biochar/sand. Our findings emphasize the importance of monitoring biochar’s functionality to eliminate bacterial pollutants from contaminated water.
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Jing X, Wu Y, Wang D, Qu C, Liu J, Gao C, Mohamed A, Huang Q, Cai P, Ashry NM. Ionic Strength-Dependent Attachment of Pseudomonas aeruginosa PAO1 on Graphene Oxide Surfaces. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:16707-16715. [PMID: 36378621 DOI: 10.1021/acs.est.1c08672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Graphene oxide (GO) is a widely used antimicrobial and antibiofouling material in surface modification. Although the antibacterial mechanisms of GO have been thoroughly elucidated, the dynamics of bacterial attachment on GO surfaces under environmentally relevant conditions remain largely unknown. In this study, quartz crystal microbalance with dissipation monitoring (QCM-D) was used to examine the dynamic attachment processes of a model organism Pseudomonas aeruginosa PAO1 onto GO surface under different ionic strengths (1-600 mM NaCl). Our results show the highest bacterial attachment at moderate ionic strengths (200-400 mM). The quantitative model of QCM-D reveals that the enhanced bacterial attachment is attributed to the higher contact area between bacterial cells and GO surface. The extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory and atomic force microscopy (AFM) analysis were employed to reveal the mechanisms of the bacteria-GO interactions under different ionic strengths. The strong electrostatic and steric repulsion at low ionic strengths (1-100 mM) was found to hinder the bacteria-GO interaction, while the limited polymer bridging caused by the collapse of biopolymer layers reduced cell attachment at a high ionic strength (600 mM). These findings advance our understanding of the ionic strength-dependent bacteria-GO interaction and provide implications to further improve the antibiofouling performance of GO-modified surfaces.
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Affiliation(s)
- Xinxin Jing
- College of Resources and Environment, Huazhong Agricultural University, Wuhan430070, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan430070, China
| | - Yichao Wu
- College of Resources and Environment, Huazhong Agricultural University, Wuhan430070, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan430070, China
| | - Dengjun Wang
- School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, Alabama36849, United States
| | - Chenchen Qu
- College of Resources and Environment, Huazhong Agricultural University, Wuhan430070, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan430070, China
| | - Jun Liu
- College of Resources and Environment, Huazhong Agricultural University, Wuhan430070, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan430070, China
| | - Chunhui Gao
- College of Resources and Environment, Huazhong Agricultural University, Wuhan430070, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan430070, China
| | - Abdelkader Mohamed
- College of Resources and Environment, Huazhong Agricultural University, Wuhan430070, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan430070, China
| | - Qiaoyun Huang
- College of Resources and Environment, Huazhong Agricultural University, Wuhan430070, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan430070, China
| | - Peng Cai
- College of Resources and Environment, Huazhong Agricultural University, Wuhan430070, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan430070, China
| | - Noha Mohamed Ashry
- College of Resources and Environment, Huazhong Agricultural University, Wuhan430070, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan430070, China
- Agriculture Microbiology Department, Faculty of Agriculture, Benha University, Moshtohor, Qalubia13736, Egypt
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6
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Joshi J, Homburg SV, Ehrmann A. Atomic Force Microscopy (AFM) on Biopolymers and Hydrogels for Biotechnological Applications-Possibilities and Limits. Polymers (Basel) 2022; 14:1267. [PMID: 35335597 PMCID: PMC8949482 DOI: 10.3390/polym14061267] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/15/2022] [Accepted: 03/19/2022] [Indexed: 02/01/2023] Open
Abstract
Atomic force microscopy (AFM) is one of the microscopic techniques with the highest lateral resolution. It can usually be applied in air or even in liquids, enabling the investigation of a broader range of samples than scanning electron microscopy (SEM), which is mostly performed in vacuum. Since it works by following the sample surface based on the force between the scanning tip and the sample, interactions have to be taken into account, making the AFM of irregular samples complicated, but on the other hand it allows measurements of more physical parameters than pure topography. This is especially important for biopolymers and hydrogels used in tissue engineering and other biotechnological applications, where elastic properties, surface charges and other parameters influence mammalian cell adhesion and growth as well as many other effects. This review gives an overview of AFM modes relevant for the investigations of biopolymers and hydrogels and shows several examples of recent applications, focusing on the polysaccharides chitosan, alginate, carrageenan and different hydrogels, but depicting also a broader spectrum of materials on which different AFM measurements are reported in the literature.
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Affiliation(s)
- Jnanada Joshi
- Faculty of Engineering and Mathematics, Bielefeld University of Applied Sciences, 33619 Bielefeld, Germany
| | - Sarah Vanessa Homburg
- Faculty of Engineering and Mathematics, Bielefeld University of Applied Sciences, 33619 Bielefeld, Germany
| | - Andrea Ehrmann
- Faculty of Engineering and Mathematics, Bielefeld University of Applied Sciences, 33619 Bielefeld, Germany
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7
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Villalba M, Venturelli L, Arnal L, Masson C, Dietler G, Vela ME, Yantorno O, Kasas S. Effect of antibiotics on mechanical properties of Bordetella pertussis examined by atomic force microscopy. Micron 2022; 155:103229. [DOI: 10.1016/j.micron.2022.103229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 12/12/2021] [Accepted: 01/24/2022] [Indexed: 11/28/2022]
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8
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Jiang W, Yu Z, Cao X, Jiang K, Yuan Y, Anderson DM, Song X. Effects of soluble organics on the settling rate of modified clay and development of improved clay formulations for harmful algal bloom control. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 289:117964. [PMID: 34426199 DOI: 10.1016/j.envpol.2021.117964] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 08/09/2021] [Accepted: 08/11/2021] [Indexed: 06/13/2023]
Abstract
For many years, the dispersal of modified clay (MC) has been used to control harmful algal blooms (HABs) in coastal waters of China. MC flocculation efficiency can be influenced by many factors in variable and complex natural environments, including high concentrations of dissolved organic matter (DOM) in the water to be treated. Since many HABs occur in nearshore waters where DOM concentrations are high, this is a significant problem that requires urgent attention. This study involved the use of humic acid as a representative form of DOM to study the influence of organic matter on the MC flocculation process. At high concentrations, humic acid was adsorbed onto MC particles, resulting in a decrease in surface potential and an increase in electrostatic repulsion between the clay particles; this decreased the MC settling rate and increased the water clarification time. Flocs were characterized by their relatively small particle size, high particle concentration, and low collision efficiency, which together resulted in slow clarification of the water after MC spraying. Based on the mechanism of the DOM-MC interaction and combined with the Derjaguin-Landau-Verwey-Overbeek theory and theoretical considerations of clay surface modification, the "ionic atmosphere compression" method was used to improve MC flocculation efficiency in high-organic water. This method increased the ionic strength of the clay stock solution by adding salt, thereby compressing the ionic atmosphere of MC particles and lowering the potential barrier, allowing the MC particles in the treated water to flocculate rapidly and form large flocs, followed by further floc growth and rapid settling via differential sedimentation. The settling rate of MCs improved by a factor of two and the removal efficiency of the HAB cells increased by 7-28%. This study provides important baseline information that will extend the application of MC to HAB control in water bodies with high organic loadings.
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Affiliation(s)
- Wenbin Jiang
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Functional Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, PR China
| | - Zhiming Yu
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Functional Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, PR China.
| | - Xihua Cao
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Functional Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, PR China
| | - Kaiqin Jiang
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Functional Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, PR China
| | - Yongquan Yuan
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Functional Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, PR China
| | | | - Xiuxian Song
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Functional Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, PR China
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9
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Zhu T, Merroun ML, Arhonditsis G, Dittrich M. Attachment on mortar surfaces by cyanobacterium Gloeocapsa PCC 73106 and sequestration of CO 2 by microbially induced calcium carbonate. Microbiologyopen 2021; 10:e1243. [PMID: 34713603 PMCID: PMC8516036 DOI: 10.1002/mbo3.1243] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 09/25/2021] [Accepted: 09/27/2021] [Indexed: 11/08/2022] Open
Abstract
Cyanobacterial carbonate precipitation induced by cells and extracellular polymeric substances (EPS) enhances mortar durability. The percentage of cell/EPS attachment regulates the effectiveness of the mortar restoration. This study investigates the cell coverage on mortar and microbially induced carbonate precipitation. Statistical analysis of results from scanning electron and fluorescence microscopy shows that the cell coverage was higher in the presence of UV-killed cells than living cells. Cells are preferably attached to cement paste than sand grains, with a difference of one order of magnitude. The energy-dispersive X-ray spectroscopy analyses and Raman mapping suggest cyanobacteria used atmospheric CO2 to precipitate carbonates.
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Affiliation(s)
- Tingting Zhu
- Biogeochemistry LaboratoryDepartment of Physical and Environmental SciencesUniversity of Toronto ScarboroughTorontoONCanada
- Present address:
Department of Geography, Geomatics and EnvironmentDepartment of Mathematical and Computational SciencesUniversity of Toronto Mississauga3359 Mississauga RdMississaugaOntarioL5L 1C6Canada
| | | | - George Arhonditsis
- Ecological Modelling LaboratoryDepartment of Physical and Environmental SciencesUniversity of Toronto ScarboroughTorontoOntarioCanada
| | - Maria Dittrich
- Biogeochemistry LaboratoryDepartment of Physical and Environmental SciencesUniversity of Toronto ScarboroughTorontoONCanada
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10
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Chepkwony NK, Brun YV. A polysaccharide deacetylase enhances bacterial adhesion in high-ionic-strength environments. iScience 2021; 24:103071. [PMID: 34568792 PMCID: PMC8449245 DOI: 10.1016/j.isci.2021.103071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 07/19/2021] [Accepted: 08/27/2021] [Indexed: 11/30/2022] Open
Abstract
Differences in ionic strength, pH, temperature, shear forces, and other environmental factors impact adhesion, and organisms have evolved various strategies to optimize their adhesins for their specific environmental conditions. Many species of Alphaproteobacteria, including members of the order Caulobacterales, use a polar adhesin, called holdfast, for surface attachment and subsequent biofilm formation in both freshwater and marine environments. Hirschia baltica, a marine member of Caulobacterales, produces a holdfast adhesin that tolerates a drastically higher ionic strength than the holdfast produced by its freshwater relative, Caulobacter crescentus. In this work, we show that the holdfast polysaccharide deacetylase HfsH plays an important role in adherence in high-ionic-strength environments. We show that increasing expression of HfsH improves holdfast binding in high-ionic-strength environments. We conclude that HfsH plays a role in modulating holdfast binding at high ionic strength and hypothesize that this modulation occurs through varied deacetylation of holdfast polysaccharides. The polysaccharide deacetylase HfsH is required for H. baltica adhesion Holdfast polysaccharides in H. baltica ΔhfsH lack cohesive and adhesive properties HfsH expression correlates positively with holdfast binding in high ionic strength HfsH is an important factor for adherence in high-ionic-strength environments
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Affiliation(s)
- Nelson K Chepkwony
- Département de microbiologie, infectiologie et immunologie, Université de Montréal, C.P. 6128, succ. Centre-ville, Montréal, QC H3C 3J7, Canada
| | - Yves V Brun
- Département de microbiologie, infectiologie et immunologie, Université de Montréal, C.P. 6128, succ. Centre-ville, Montréal, QC H3C 3J7, Canada
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11
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Shariq AF, Beyenal H, Akin ID. Biofilm addition improves sand strength over a wide range of saturations. Biofilm 2021; 3:100050. [PMID: 34258578 PMCID: PMC8260866 DOI: 10.1016/j.bioflm.2021.100050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 04/12/2021] [Accepted: 05/30/2021] [Indexed: 11/30/2022] Open
Abstract
Bio-mediated ground improvement is an attractive alternative to traditional admixtures for strength improvement of shallow surfaces because it is environmentally friendly. Since biofilms contain extracellular polymeric substances (EPS), they can be considered as an alternative to current technologies to improve soil strength. EPS containing biofilms are porous materials with charged surfaces, and therefore adsorption and capillary condensation can result in water retention. Currently, most of the literature work only tested soil improvement under the dry condition. Therefore, the influence of water retention by biofilms on the strength of improved soil remains unclear. Our goal is to evaluate the strength of a biofilm-enhanced sand over a wide range of saturations and explain the trends through the suction stress characteristic curve (SSCC), which quantifies interparticle adsorptive, capillary, and cementation forces as a function of saturation. We used homogenized anaerobic granule biofilms from an existing upflow anaerobic sludge blanket reactor and mixed it with sand to test the strength of a poorly-graded sand in a wide range of saturations, S (between 0.02 S and 0.74 S). We found that biofilm treatment of sand increases soil strength through cementation over a wide range of saturations and through adsorptive forces among sand, biofilm surfaces, and water molecules at low saturations (S < ~0.3). Our results suggested that homogenized biofilms mixed with sand can be used to improve the strength of sand over a wide range of saturations.
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Affiliation(s)
- Ahmad Faysal Shariq
- Washington State University, Department of Civil and Environmental Engineering, Pullman, WA, 99164, USA
| | - Haluk Beyenal
- Washington State University, Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Pullman, WA, 99164, USA
| | - Idil Deniz Akin
- Colf Distinguished Professor in Geotechnical Engineering, Washington State University, Department of Civil and Environmental Engineering, Pullman, WA, 99164, USA
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12
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Luengo GS, Fameau AL, Léonforte F, Greaves AJ. Surface science of cosmetic substrates, cleansing actives and formulations. Adv Colloid Interface Sci 2021; 290:102383. [PMID: 33690071 DOI: 10.1016/j.cis.2021.102383] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 02/04/2021] [Accepted: 02/06/2021] [Indexed: 12/22/2022]
Abstract
The development of shampoo and cleansing formulations in cosmetics is at a crossroads due to consumer demands for better performing, more natural products and also the strong commitment of cosmetic companies to improve the sustainability of cosmetic products. In order to go beyond traditional formulations, it is of great importance to clearly establish the science behind cleansing technologies and appreciate the specificity of cleansing biological surfaces such as hair and skin. In this review, we present recent advances in our knowledge of the physicochemical properties of the hair surface from both an experimental and a theoretical point of view. We discuss the opportunities and challenges that newer, sustainable formulations bring compared to petroleum-based ingredients. The inevitable evolution towards more bio-based, eco-friendly ingredients and sustainable formulations requires a complete rethink of many well-known physicochemical principles. The pivotal role of digital sciences and modelling in the understanding and conception of new ingredients and formulations is discussed. We describe recent numerical approaches that take into account the specificities of the hair surface in terms of structuration, different methods that study the adsorption of formulation ingredients and finally the success of new data-driven approaches. We conclude with practical examples on current formulation efforts incorporating bio-surfactants, controlling foaming and searching for new rheological properties.
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Eskhan AO, Abu-Lail NI. Force-Averaging DLVO Model Predictions of the Adhesion Strengths Quantified for Pathogenic Listeria monocytogenes EGDe Grown under Variable pH Stresses. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:8947-8964. [PMID: 32633976 DOI: 10.1021/acs.langmuir.0c01500] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The roles of the bacterial surface biopolymers of pathogenic Listeria monocytogenes EGDe grown under variable pH conditions in governing their adhesion to a model surface of silicon nitride were investigated using atomic force microscopy under water. Our results indicated that the adhesion forces were the highest for cells cultured in media adjusted to pH 7 followed by 1.39, 1.49, 1.57, and 2.18-fold reductions at pH 6, 8, 9, and 5, respectively. Adhesion energies followed the same trends with 1.35, 1.67, 2.20, and 2.79-fold reductions in energies at pH 6, 8, 9, and 5, respectively, compared to the energy measured at pH 7. Furthermore, the structural properties of the bacterial surface biopolymer brush represented by the biopolymer brush thickness (Lo) and the molecular density (Γ) were determined by fitting a steric model of repulsion to the approach force-distance data. The Lo values followed the same trends as adhesion forces and energies, with thickness being highest at pH 7 followed by 1.82, 2.99, 3.11, and 4.66-fold reductions at pH 6, 8, 9, and 5, respectively. Γ was the highest at pH 5 and was followed by 1.26, 1.27, 1.70, and 2.82-fold reductions at pH 8, 9, 6, and 7, respectively. Our results indicated that bacterial adhesion forces and energies increased linearly with the product of Lo and Γ representing the number of biopolymers per unit length of the bacterial surface. To predict the adhesion forces and energies measured, a force-averaging model of the soft-particle analysis of the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory was used. In addition to the standard parameters accounted for in the soft-particle analysis of the DLVO theory such as surface potential, hydrophobicity, and size, this averaging model incorporates in it structural bacterial parameters such as Lo and Γ as well as a surface coverage factor (ϕ) that represents the fraction of the bacterial surface covered by biopolymers. When the soft-particle analysis of DLVO was considered, repulsive hydrogen bond strengths were predicted at close distances of approach (<0.3 nm). In comparison, the force-averaging model predicted that attractive hydrogen bonds dominate the bacterial adhesion strengths quantified. The highest adhesion quantified for cells grown at pH 7 was related to longer and more spaced biopolymers, higher contents of cellular carbohydrates, and more hydrophilic biopolymers, each of which contributes to higher possibilities for hydrogen bonding formation. These results are significant in designing new strategies that aim at controlling bacterial adhesion to surfaces.
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Affiliation(s)
- Asma O Eskhan
- The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, Washington 99164, United States
| | - Nehal I Abu-Lail
- Department of Biomedical Engineering and Chemical Engineering, The University of Texas at San Antonio, San Antonio, Texas, 78249, United States
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14
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Gordesli-Duatepe FP, Park BJ, Kawas LH, Abu-Lail NI. Atomic Force Microscopy Investigation of the Contributions of Listeria monocytogenes Cell-Wall Biomacromolecules to Their Adherence and Mechanics. J Phys Chem B 2020; 124:5872-5883. [PMID: 32544332 DOI: 10.1021/acs.jpcb.0c04025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this work, the contributions of the pathogenic Listeria monocytogenes cell-wall biomacromolecules to the bacterial mechanics and adhesion to a model inert surface of silicon nitride in water were investigated by atomic force microscopy. Chemical ethylenediaminetetraacetic acid (EDTA) and biological enzymatic trypsin treatments of cells were performed to partially or totally remove the bacterial cell-wall proteins and carbohydrates. Removal of 48.2% proteins and 29.2% of carbohydrates from the cell-wall of the bacterium by the EDTA treatment resulted in a significant decrease in the length of the bacterial cell-wall biomacromolecules and an increase in the rigidity of the bacterial cells as predicted from fitting a model of steric repulsion to the force-distance approach data and classic Hertz model to the indentation-force data, respectively. In comparison, removal of almost all the cell-wall proteins (99.5% removal) and 8.6% of cell-wall carbohydrates by the trypsin treatment resulted in an increase in the elasticity of the bacterial cells, an increase in the extension of the cell-wall biomacromolecules, and a significant decrease in their apparent grafting densities. In addition, adhesion strength of native-untreated L. monocytogenes to silicon nitride in water decreased by 30% on average after the EDTA treatment and further decreased by 60% on average after the trypsin treatment, showing a positive correlation with the% removal of cell-wall proteins by the EDTA and trypsin treatments, respectively.
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Affiliation(s)
- F Pinar Gordesli-Duatepe
- Department of Genetics and Bioengineering, Faculty of Engineering, Izmir University of Economics, 35330 Izmir, Turkey
| | - Bong J Park
- The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, Washington 99164, United States
| | - Leen H Kawas
- Department of Veterinary and Comparative Anatomy, Pharmacology, and Physiology, Washington State University Pullman, Washington 99164-6520, United States
| | - Nehal I Abu-Lail
- Department of Biomedical Engineering and Chemical Engineering, The University of Texas at San Antonio, San Antonio, Texas 78249, United States
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15
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Variations in the Morphology, Mechanics and Adhesion of Persister and Resister E. coli Cells in Response to Ampicillin: AFM Study. Antibiotics (Basel) 2020; 9:antibiotics9050235. [PMID: 32392749 PMCID: PMC7277365 DOI: 10.3390/antibiotics9050235] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 04/29/2020] [Accepted: 05/04/2020] [Indexed: 12/12/2022] Open
Abstract
Persister bacterial cells are great at surviving antibiotics. The phenotypic means by which they do that are underexplored. As such, atomic force microscope (AFM) was used to quantify the contributions of the surface properties of the outer membrane of multidrug resistance (MDR)-Escherichia coli Strains (A5 and A9) in the presence of ampicillin at minimum inhibitory concentration (MIC) (resistant cells) and at 20× MIC (persistent cells). The properties quantified were morphology, root mean square (RMS) roughness, adhesion, elasticity, and bacterial surface biopolymers' thickness and grafting density. Compared to untreated cells, persister cells of E. coli A5 increased their RMS, adhesion, apparent grafting density, and elasticity by 1.2, 3.4, 2.0, and 3.3 folds, respectively, and decreased their surface area and brush thickness by 1.3 and 1.2 folds, respectively. Similarly, compared to untreated cells, persister cells of E. coli A9 increased their RMS, adhesion and elasticity by 1.6, 4.4, and 4.5 folds, respectively; decreased their surface area and brush thickness by 1.4 and 1.6 folds, respectively; and did not change their grafting densities. Our results indicate that resistant and persistent E. coli A5 cells battled ampicillin by decreasing their size and going through dormancy. The resistant E. coli A9 cells resisted ampicillin through elongation, increased surface area, and adhesion. In contrast, the persistent E. coli A9 cells resisted ampicillin through increased roughness, increased surface biopolymers' grafting densities, increased cellular elasticities, and decreased surface areas. Mechanistic insights into how the resistant and persistent E. coli cells respond to ampicillin's treatment are instrumental to guide design efforts exploring the development of new antibiotics or renovating the existing antibiotics that may kill persistent bacteria by combining more than one mechanism of action.
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16
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Xie W, Li J, Sun F, Dong W. Ultrasonication favors TiO 2 nano-particles dispersion in PVDF ultrafiltration membrane to effectively enhance membrane hydrophilicity and anti-fouling capability. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:9503-9519. [PMID: 31919824 DOI: 10.1007/s11356-019-06862-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 10/22/2019] [Indexed: 06/10/2023]
Abstract
The influence of ultrasonication on membrane performance was investigated by two ultrasonication modes, direct and indirect ultrasonication as pretreatment, and simply improved PVDF-TiO2 membranes' performance was systematically compared. Ultrasound intensity of 100% and ultrasonication time ranged from 1 to 2 h positively affect membrane permeability. Characterization results manifested that membrane structure was eventually optimized with an even nano-TiO2 dispersion by direct ultrasonication. Analysis of surface roughness reflected that PVDF-TiO2 (MS-U2) surface morphological pattern was peak-valley structure that resisted fouling greatly. A good fitting of experimental result and Tansel's simulation illustrated that anti-fouling ability was realized direct ultrasonication modified membrane. PVDF-TiO2 (MS-U2) membrane showing the lowest |τ| reflecting the time required to reach a certain level of the fouling degree was the lowest. Relying upon modified Hermia's model analysis, protein blockage within the membrane pore was one major fouling mechanism; surface blockage degree of PVDF-TiO2 (MS-U2) was relative slight. Fouling mechanism analyzed by two models reflected that PVDF-TiO2 (MS-U2) membrane exhibited a higher anti-protein fouling ability during cross-flow filtration process.
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Affiliation(s)
- Wanying Xie
- Shenzhen Key Laboratory of Water Resource Utilization and Environmental Pollution Control, Harbin Institute of Technology, Shenzhen, 518055, Guangdong Province, China
| | - Ji Li
- Shenzhen Key Laboratory of Water Resource Utilization and Environmental Pollution Control, Harbin Institute of Technology, Shenzhen, 518055, Guangdong Province, China
| | - Feiyun Sun
- Shenzhen Key Laboratory of Water Resource Utilization and Environmental Pollution Control, Harbin Institute of Technology, Shenzhen, 518055, Guangdong Province, China.
| | - Wenyi Dong
- Shenzhen Key Laboratory of Water Resource Utilization and Environmental Pollution Control, Harbin Institute of Technology, Shenzhen, 518055, Guangdong Province, China
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17
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Goss JW, Volle CB. Using Atomic Force Microscopy To Illuminate the Biophysical Properties of Microbes. ACS APPLIED BIO MATERIALS 2019; 3:143-155. [PMID: 32851362 DOI: 10.1021/acsabm.9b00973] [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] [Indexed: 12/15/2022]
Abstract
Since its invention in 1986, atomic force microscopy (AFM) has grown from a system designed for imaging inorganic surfaces to a tool used to probe the biophysical properties of living cells and tissues. AFM is a scanning probe technique and uses a pyramidal tip attached to a flexible cantilever to scan across a surface, producing a highly detailed image. While many research articles include AFM images, fewer include force-distance curves, from which several biophysical properties can be determined. In a single force-distance curve, the cantilever is lowered and raised from the surface, while the forces between the tip and the surface are monitored. Modern AFM has a wide variety of applications, but this review will focus on exploring the mechanobiology of microbes, which we believe is of particular interest to those studying biomaterials. We briefly discuss experimental design as well as different ways of extracting meaningful values related to cell surface elasticity, cell stiffness, and cell adhesion from force-distance curves. We also highlight both classic and recent experiments using AFM to illuminate microbial biophysical properties.
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Affiliation(s)
- John W Goss
- Department of Biological Sciences, Wellesley College, Wellesley, Massachusetts 02481, United States
| | - Catherine B Volle
- Departments of Biology and Chemistry, Cornell College, Mount Vernon, Iowa 52314, United States
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18
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Lebedeva IO, Shavykin OV, Neelov IM, Zhulina EB, Leermakers FAM, Borisov OV. Non-linear elasticity effects and stratification in brushes of branched polyelectrolytes. J Chem Phys 2019; 151:214902. [PMID: 31822102 DOI: 10.1063/1.5130580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Brushes formed by arm-tethered starlike polyelectrolytes may exhibit internal segregation into weakly and strongly extended populations (stratified two-layer structure) when strong ionic intermolecular repulsions induce stretching of the tethers up to the limit of their extensibility. We propose an approximate Poisson-Boltzmann theory for analysis of the structure of the stratified brush and compare it with results of numerical self-consistent field modeling. Both analytical and numerical models point to the formation of a narrow cloud of counterions (internal double electrical layer) localized inside a stratified brush at the boundary between the layers.
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Affiliation(s)
- Inna O Lebedeva
- Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et Les Matériaux, UMR 5254 CNRS UPPA, 64053 Pau, France
| | - Oleg V Shavykin
- St. Petersburg National University of Informational Technologies, Mechanics and Optics, 197101 St. Petersburg, Russia
| | - Igor M Neelov
- St. Petersburg National University of Informational Technologies, Mechanics and Optics, 197101 St. Petersburg, Russia
| | - Ekaterina B Zhulina
- St. Petersburg National University of Informational Technologies, Mechanics and Optics, 197101 St. Petersburg, Russia
| | - Frans A M Leermakers
- Physical Chemistry and Soft Matter, Wageningen University, 6703 HB Wageningen, The Netherlands
| | - Oleg V Borisov
- Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et Les Matériaux, UMR 5254 CNRS UPPA, 64053 Pau, France
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19
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Fecal indicator bacteria and virus removal in stormwater biofilters: Effects of biochar, media saturation, and field conditioning. PLoS One 2019; 14:e0222719. [PMID: 31553761 PMCID: PMC6760807 DOI: 10.1371/journal.pone.0222719] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 09/05/2019] [Indexed: 11/23/2022] Open
Abstract
Stormwater biofilters are used to attenuate the flow and volume of runoff and reduce pollutant loading to aquatic systems. However, the capacity of biofilters to remove microbial contaminants remains inadequate. While biochar has demonstrated promise as an amendment to improve microbial removal in laboratory-scale biofilters, it is uncertain if the results are generalizable to the field. To assess biochar performance in a simulated field setting, sand and biochar-amended sand biofilters were periodically dosed with natural stormwater over a 61-week conditioning phase. Impact of media saturation was assessed by maintaining biofilters with and without a saturated zone. Biochar-amended biofilters demonstrated improved Escherichia coli removal over sand biofilters during the first 31 weeks of conditioning though media type did not impact E. coli removal during the last 30 weeks of conditioning. Presence of a saturated zone was not a significant factor influencing E. coli removal across the entire conditioning phase. Following conditioning, biofilters underwent challenge tests using stormwater spiked with wastewater to assess their capacity to remove wastewater-derived E. coli, enterococci, and male-specific (F+) coliphage. In challenge tests, biochar-amended biofilters demonstrated enhanced removal of all fecal indicators relative to sand biofilters. Additionally, saturated biofilters demonstrated greater removal of fecal indicators than unsaturated biofilters for both media types. Discrepant conclusions from the conditioning phase and challenge tests may be due to variable influent chemistry, dissimilar transport of E. coli indigenous to stormwater and those indigenous to wastewater, and differences in E. coli removal mechanisms between tests. Mobilization tests conducted following challenge tests showed minimal (<2.5%) observable mobilization of fecal indicators, regardless of media type and presence of a saturated zone. While our results emphasize the challenge of translating biochar’s performance from the laboratory to the field, findings of this study inform biofilter design to remove microbial contaminants from urban stormwater.
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20
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Deliorman M, Duatepe FPG, Davenport EK, Fransson BA, Call DR, Beyenal H, Abu-Lail NI. Responses of Acinetobacter baumannii Bound and Loose Extracellular Polymeric Substances to Hyperosmotic Agents Combined with or without Tobramycin: An Atomic Force Microscopy Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:9071-9083. [PMID: 31184900 PMCID: PMC7607972 DOI: 10.1021/acs.langmuir.9b01227] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
In this work, contributions of extracellular polymeric substances (EPS) to the nanoscale mechanisms through which the multidrug-resistant Acinetobacter baumannii responds to antimicrobial and hyperosmotic treatments were investigated by atomic force microscopy. Specifically, the adhesion strengths to a control surface of silicon nitride (Si3N4) and the lengths of bacterial surface biopolymers of bound and loose EPS extracted from A. baumannii biofilms were quantified after individual or synergistic treatments with hyperosmotic agents (NaCl and maltodextrin) and an antibiotic (tobramycin). In the absence of any treatment, the loose EPS were significantly longer in length and higher in adhesion to Si3N4 than the bound EPS. When used individually, the hyperosmotic agents and tobramycin collapsed the A. baumannii bound and loose EPS. The combined treatment of maltodextrin with tobramycin collapsed only the loose EPS and did not alter the adhesion of both bound and loose EPS to Si3N4. In addition, the combined treatment was not as effective in collapsing the EPS molecules as when tobramycin was applied alone. Finally, the effects of treatments were dose-dependent. Altogether, our findings suggest that a sequential treatment could be effective in treating A. baumannii biofilms, in which a hyperosmotic agent is used first to collapse the EPS and limit the diffusion of nutrients into the biofilm, followed by the use of an antibiotic to kill the bacterial cells that escape from the biofilm because of starvation.
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Affiliation(s)
- Muhammedin Deliorman
- Division of Engineering, New York University Abu Dhabi, P.O. Box 129188, Abu Dhabi, UAE
| | | | - Emily K. Davenport
- Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, 99164 Pullman, Washington, United States
| | - Boel A. Fransson
- Department of Veterinary Clinical Sciences, Washington State University, 99164 Pullman, Washington, United States
| | - Douglas R. Call
- Paul G. Allen School for Global Animal Health, Washington State University, 99164 Pullman, Washington, United States
| | - Haluk Beyenal
- Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, 99164 Pullman, Washington, United States
| | - Nehal I. Abu-Lail
- Department of Biomedical Engineering, University of Texas at San Antonio, 78249 San Antonio, Texas, United States
- Corresponding Author:. Phone: +1 210 458 8131
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21
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Alam F, Kumar S, Varadarajan KM. Quantification of Adhesion Force of Bacteria on the Surface of Biomaterials: Techniques and Assays. ACS Biomater Sci Eng 2019; 5:2093-2110. [DOI: 10.1021/acsbiomaterials.9b00213] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fahad Alam
- Biomaterials Processing and Characterization Laboratory, Materials Science and Engineering, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India
- Department of Mechanical and Materials Engineering, Khalifa University of Science and Technology, Masdar Institute, Masdar City, Abu Dhabi United Arab Emirates
| | - Shanmugam Kumar
- Department of Mechanical and Materials Engineering, Khalifa University of Science and Technology, Masdar Institute, Masdar City, Abu Dhabi United Arab Emirates
| | - Kartik M. Varadarajan
- Department of Orthopaedic Surgery, Harvard Medical School, A-111, 25 Shattuck Street, Boston, Massachusetts 02115, United States
- Department of Orthopaedic Surgery, Harris Orthopaedics Laboratory, Massachusetts General Hospital, 55 Fruit Street, Boston, Massachusetts 02114, United States
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22
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Uzoechi SC, Abu-Lail NI. Changes in Cellular Elasticities and Conformational Properties of Bacterial Surface Biopolymers of Multidrug-Resistant Escherichia coli (MDR- E. coli) Strains in Response to Ampicillin. ACTA ACUST UNITED AC 2019; 5. [PMID: 31179402 PMCID: PMC6550352 DOI: 10.1016/j.tcsw.2019.100019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The roles of the thicknesses and grafting densities of the surface biopolymers of four multi-drug resistant (MDR) Escherichia coli bacterial strains that varied in their biofilm formation in controlling cellular elasticities after exposure to ampicillin were investigated using atomic force microscopy. Exposure to ampicillin was carried out at minimum inhibitory concentrations for different duration times. Our results indicated that the four strains resisted ampicillin through variable mechanisms. Strain A5 did not change its cellular properties upon exposure to ampicillin and as such resisted ampicillin through dormancy. Strain H5 increased its biopolymer brush thickness, adhesion and biofilm formation and kept its roughness, surface area and cell elasticity unchanged upon exposure to ampicillin. As such, this strain likely limits the diffusion of ampicillin by forming strong biofilms. At three hours’ exposure to ampicillin, strains D4 and A9 increased their roughness, surface areas, biofilm formation, and brush thicknesses and decreased their elasticities. Therefore, at short exposure times to ampicillin, these strains resisted ampicillin through forming strong biofilms that impede ampicillin diffusion. At eight hours’ exposure to ampicillin, strains D4 and A9 collapsed their biopolymers, increased their apparent grafting densities and increased their cellular elasticities. Therefore, at long exposure times to ampicillin, cells utilized their higher rigidity to reduce the diffusion of ampicillin into the cells. The findings of this study clearly point to the potential of using the nanoscale characterization of MDR bacterial properties as a means to monitor cell modifications that enhance “phenotypic antibiotic resistance”.
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Affiliation(s)
- Samuel C Uzoechi
- Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA 99164.,Department of Biomedical Technology, Federal University of Technology, Owerri, PMB 1526, Owerri, Nigeria
| | - Nehal I Abu-Lail
- Department of Biomedical Engineering, The University of Texas at San Antonio, San Antonio, TX, 78249
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23
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Uzoechi SC, Abu-Lail NI. The Effects of β-Lactam Antibiotics on Surface Modifications of Multidrug-Resistant Escherichia coli: A Multiscale Approach. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2019; 25:135-150. [PMID: 30869575 PMCID: PMC6599534 DOI: 10.1017/s1431927618015696] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Possible multidrug-resistant (MDR) mechanisms of four resistant strains of Escherichia coli to a model β-lactam, ampicillin, were investigated using contact angle measurements of wettability, crystal violet assays of permeability, biofilm formation, fluorescence imaging, and nanoscale analyses of dimensions, adherence, and roughness. Upon exposure to ampicillin, one of the resistant strains, E. coli A5, changed its phenotype from elliptical to spherical, maintained its roughness and biofilm formation abilities, decreased its length and surface area, maintained its cell wall integrity, increased its hydrophobicity, and decreased its nanoscale adhesion to a model surface of silicon nitride. Such modifications are suggested to allow these cells to conserve energy during metabolic dormancy. In comparison, resistant strains E. coli D4, A9, and H5 elongated their cells, increased their roughness, increased their nanoscale adhesion forces, became more hydrophilic, and increased their biofilm formation upon exposure to ampicillin. These results suggest that these strains resisted ampicillin through biofilm formation that possibly introduces diffusion limitations to antibiotics. Investigations of how MDR bacterial cells modify their surfaces in response to antibiotics can guide research efforts aimed at designing more effective antibiotics and new treatment strategies for MDR bacterial infections.
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Affiliation(s)
- Samuel C. Uzoechi
- Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA 99164, USA
| | - Nehal I. Abu-Lail
- Department of Biomedical Engineering, The University of Texas at San Antonio, San Antonio, TX 78249, USA
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24
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Yang Y, Hou J, Wang P, Wang C, Wang X, You G. Influence of extracellular polymeric substances on cell-NPs heteroaggregation process and toxicity of cerium dioxide NPs to Microcystis aeruginosa. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 242:1206-1216. [PMID: 30118909 DOI: 10.1016/j.envpol.2018.08.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 07/15/2018] [Accepted: 08/02/2018] [Indexed: 06/08/2023]
Abstract
The presence of abundant extracellular polymeric substances (EPS) play a vital role in affecting heteroaggregation process and toxicity of nanoparticles (NPs) to Microcystis aeruginosa. Interactions between n-CeO2 and cyanobacteria with/without EPS and the toxicity of n-CeO2 to M. aeruginosa were investigated in this study. Aggregation kinetics of n-CeO2 under both soluble EPS (SEPS) and bound EPS (BEPS) indicated the presence of EPS could induced the formation of EPS-NPs aggregates. Heteroaggregation between cells and n-CeO2 was confirmed through co-settling experiment and SEM-EDS observation. SEPS contributed to the observable heteroaggregation using spectral measurement. Heteroaggregation between cells and n-CeO2 under no BEPS was hardly obtained through spectral measurement, but SEM-EDS observation convinced this process. And the DLVO theory explained this heteroaggregation process under various EPS conditions, where the energy barrier decreased with gradual EPS extraction. In addition, the order for 96 h half growth inhibition concentration (IC50) was Raw M9 > M9-SEPS > M9+BEPS > M9-BEPS. These results revealed that not all heteroaggregation between cell-NPs can lead to the NPs toxicity to cells. BEPS act more important role in buffering against the toxicity of NPs from ambient adverse factors, but SEPS increase the stability of NPs which could aggravate the adverse effects of NPs in the environment.
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Affiliation(s)
- Yangyang Yang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Jun Hou
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China.
| | - Peifang Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Chao Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Xun Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Guoxiang You
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
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25
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Role of ionic strength in the retention and initial attachment ofPseudomonas putidato quartz sand. Biointerphases 2018; 13:041005. [DOI: 10.1116/1.5027735] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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26
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Hall AR, Geoghegan M. Polymers and biopolymers at interfaces. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:036601. [PMID: 29368695 DOI: 10.1088/1361-6633/aa9e9c] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
This review updates recent progress in the understanding of the behaviour of polymers at surfaces and interfaces, highlighting examples in the areas of wetting, dewetting, crystallization, and 'smart' materials. Recent developments in analysis tools have yielded a large increase in the study of biological systems, and some of these will also be discussed, focussing on areas where surfaces are important. These areas include molecular binding events and protein adsorption as well as the mapping of the surfaces of cells. Important techniques commonly used for the analysis of surfaces and interfaces are discussed separately to aid the understanding of their application.
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Affiliation(s)
- A R Hall
- Department of Physics and Astronomy, University of Sheffield, Hounsfield Road, Sheffield S3 7RH, United Kingdom. Fraunhofer Project Centre for Embedded Bioanalytical Systems, Dublin City University, Glasnevin, Dublin 9, Ireland
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27
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Layered Structure and Complex Mechanochemistry Underlie Strength and Versatility in a Bacterial Adhesive. mBio 2018; 9:mBio.02359-17. [PMID: 29437925 PMCID: PMC5801468 DOI: 10.1128/mbio.02359-17] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
While designing synthetic adhesives that perform in aqueous environments has proven challenging, microorganisms commonly produce bioadhesives that efficiently attach to a variety of substrates, including wet surfaces. The aquatic bacterium Caulobacter crescentus uses a discrete polysaccharide complex, the holdfast, to strongly attach to surfaces and resist flow. The holdfast is extremely versatile and has impressive adhesive strength. Here, we used atomic force microscopy in conjunction with superresolution microscopy and enzymatic assays to unravel the complex structure of the holdfast and to characterize its chemical constituents and their role in adhesion. Our data support a model whereby the holdfast is a heterogeneous material organized as two layers: a stiffer nanoscopic core layer wrapped into a sparse, far-reaching, flexible brush layer. Moreover, we found that the elastic response of the holdfast evolves after surface contact from initially heterogeneous to more homogeneous. From a composition point of view, besides N-acetyl-d-glucosamine (NAG), the only component that had been identified to date, our data show that the holdfast contains peptides and DNA. We hypothesize that, while polypeptides are the most important components for adhesive force, the presence of DNA mainly impacts the brush layer and the strength of initial adhesion, with NAG playing a primarily structural role within the core. The unanticipated complexity of both the structure and composition of the holdfast likely underlies its versatility as a wet adhesive and its distinctive strength. Continued improvements in understanding of the mechanochemistry of this bioadhesive could provide new insights into how bacteria attach to surfaces and could inform the development of new adhesives.IMPORTANCE There is an urgent need for strong, biocompatible bioadhesives that perform underwater. To strongly adhere to surfaces and resist flow underwater, the bacterium Caulobacter crescentus produces an adhesive called the holdfast, the mechanochemistry of which remains undefined. We show that the holdfast is a layered structure with a stiff core layer and a polymeric brush layer and consists of polysaccharides, polypeptides, and DNA. The DNA appears to play a role in the structure of the brush layer and initial adhesion, the peptides in adhesive strength, and the polysaccharides in the structure of the core. The complex, multilayer organization and diverse chemistry described here underlie the distinctive adhesive properties of the holdfast and will provide important insights into the mechanisms of bacterial adhesion and bioadhesive applications.
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Archaeal tetraether lipid coatings-A strategy for the development of membrane analog spacer systems for the site-specific functionalization of medical surfaces. Biointerphases 2018; 13:011004. [PMID: 29382205 DOI: 10.1116/1.5008816] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The primary goal of our investigation was the development of a versatile immobilization matrix based on archaeal tetraether lipids that meets the most important prerequisites to render an implant surface bioactive by binding specific functional groups or functional polymers with the necessary flexibility and an optimal spatial arrangement to be bioavailable. From this point of view, it appears obvious that numerous efforts made recently to avoid initial bacterial adhesion on catheter surfaces as an important prerequisite of material associated infection episodes have shown only a limited efficiency since the bioactive entities could not be presented in an optimal conformation and a stable density. A significant improvement of this situation can be achieved by highly specific biomimetic modifications of the catheter surfaces. The term "biomimetic" originates from the fact that specific archaeal tetraether lipids were introduced to form a membrane analog monomolecular spacer system, which (1) can be immobilized on nearly all solid surfaces and (2) chemically modified to present a tailor-made functionality in contact with aqueous media either to avoid or inhibit surface fouling or to equip any implant surface with the necessary chemical functionality to enable cell adhesion and tissue integration. Ultrathin films based on tetraether lipids isolated from archaea Thermoplasma acidophilum were used as a special biomimetic immobilization matrix on the surface of commercial medical silicon elastomers. A complete performance control of the membrane analog coatings was realized in addition to biofunctionality tests, including the proof of cytotoxicity and hemocompatibility according to DIN EN ISO 10993. In order to make sure that the developed immobilization matrix including the grafted functional groups are biocompatible under in vivo-conditions, specific animal tests were carried out to examine the in vivo-performance. It can be concluded that the tetraether lipid based coating systems on silicone have shown no signs of cytotoxicity and a good hemocompatibility. Moreover, no mutagenic effects, no irritation effects, and no sensitization effects could be demonstrated. After an implantation period of 28 days, no irregularities were found.
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Zhang W, Schwab AP, White JC, Ma X. Impact of Nanoparticle Surface Properties on the Attachment of Cerium Oxide Nanoparticles to Sand and Kaolin. JOURNAL OF ENVIRONMENTAL QUALITY 2018; 47:129-138. [PMID: 29415104 DOI: 10.2134/jeq2017.07.0284] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Soil texture has been found to be a critical factor in regulating the fate and transport of cerium oxide nanoparticles (CeONPs) in the terrestrial environment. However, the underlying mechanisms for the interactions between CeONPs and different components of soil are still poorly understood. The attachment of CeONPs onto two typical components of soil (sand and kaolin) in batch experiments were investigated to provide insights into the retention and bioavailability of CeONPs in soil. Surface properties of CeONPs, including surface charge and surface coating condition, had strong impacts on the interactions between CeONPs and soil particles. Positively charged CeONPs [CeONPs(+)] displayed the greatest attachment onto kaolin, whereas the negatively charged CeONPs [CeONPs(-)] showed poorest attachment onto sand. The attachment of CeONPs onto kaolin was significantly greater than onto sand, irrespective of surface charge. Homoaggregation of CeONPs increased the size of CeONPs on the surface of sand and kaolin. Extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) calculations agreed with the experimental observations that surface charge and coating condition of CeONPs played a vital role in the homoaggregation and adsorption of CeONPs. For CeONPs(-) coated with polyvinylpyrrolidone (PVP), the steric repulsion between soil particles and CeONPs increases rapidly with the increase of maximum surface concentration of PVP. Adsorption isothermal fittings indicated that the adsorption of CeONPs onto sand and kaolin can be properly described by the Dubinin-Radushkevich isotherm. The results obtained in this study are crucial for the understanding of the fate and transport of engineered nanomaterials in the environment.
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Zhulina EB, Borisov OV. Dendritic polyelectrolyte brushes. POLYMER SCIENCE SERIES C 2017. [DOI: 10.1134/s1811238217010143] [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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31
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Zhong H, Liu G, Jiang Y, Yang J, Liu Y, Yang X, Liu Z, Zeng G. Transport of bacteria in porous media and its enhancement by surfactants for bioaugmentation: A review. Biotechnol Adv 2017; 35:490-504. [DOI: 10.1016/j.biotechadv.2017.03.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 03/20/2017] [Accepted: 03/22/2017] [Indexed: 12/13/2022]
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32
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Pioneering particle-based strategy for isolating viable bacteria from multipart soil samples compatible with Raman spectroscopy. Anal Bioanal Chem 2017; 409:3779-3788. [PMID: 28364142 DOI: 10.1007/s00216-017-0320-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 03/15/2017] [Indexed: 12/25/2022]
Abstract
The study of edaphic bacteria is of great interest, particularly for evaluating soil remediation and recultivation methods. Therefore, a fast and simple strategy to isolate various bacteria from complex soil samples using poly(ethyleneimine) (PEI)-modified polyethylene particles is introduced. The research focuses on the binding behavior under different conditions, such as the composition, pH value, and ionic strength, of the binding buffer, and is supported by the characterization of the surface properties of particles and bacteria. The results demonstrate that electrostatic forces and hydrophobicity are responsible for the adhesion of target bacteria to the particles. Distinct advantages of the particle-based isolation strategy include simple handling, enrichment efficiency, and the preservation of viable bacteria. The presented isolation method allows a subsequent identification of the bacteria using Raman microspectroscopy in combination with chemometrical methods. This is demonstrated with a dataset of five different bacteria (Escherichia coli, Bacillus subtilis, Pseudomonas fluorescens, Streptomyces tendae, and Streptomyces acidiscabies) which were isolated from spiked soil samples. In total 92% of the Raman spectra could be identified correctly.
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Leermakers F, Zhulina E, Borisov O. Interaction forces and lubrication of dendronized surfaces. Curr Opin Colloid Interface Sci 2017. [DOI: 10.1016/j.cocis.2016.09.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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34
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Chan AJ, Sarkar P, Gaboriaud F, Fontaine-Aupart MP, Marlière C. Control of interface interactions between natural rubber and solid surfaces through charge effects: an AFM study in force spectroscopic mode. RSC Adv 2017. [DOI: 10.1039/c7ra08589c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Adhesion of nanoparticles (natural rubber) is monitored by slight changes in the surface charge state of the contacting solid surfaces.
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Affiliation(s)
- Alan Jenkin Chan
- Institut des Sciences Moléculaires d'Orsay, ISMO
- Université Paris-Sud
- CNRS
- 91405 Orsay Cedex
- France
| | | | - Fabien Gaboriaud
- Manufacture Française des Pneumatiques Michelin
- F-63040 Clermont Ferrand 9
- France
| | | | - Christian Marlière
- Institut des Sciences Moléculaires d'Orsay, ISMO
- Université Paris-Sud
- CNRS
- 91405 Orsay Cedex
- France
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35
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Wang Z, Chen Z, Yang L, Tan F, Wang Y, Li Q, Chang YI, Zhong CJ, He N. Effect of surface physicochemical properties on the flocculation behavior of Bacillus licheniformis. RSC Adv 2017. [DOI: 10.1039/c6ra28057a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Flocculation model ofB. licheniformisCGMCC 2876 deduced by XDLVO and surface thermodynamic characterization.
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Affiliation(s)
- Zhi Wang
- Department of Chemical and Biochemical Engineering
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
- P. R. China
| | - Zhen Chen
- Department of Chemical and Biochemical Engineering
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
- P. R. China
| | - Lijie Yang
- Department of Chemical and Biochemical Engineering
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
- P. R. China
| | - Fen Tan
- Department of Chemical and Biochemical Engineering
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
- P. R. China
| | - Yuanpeng Wang
- Department of Chemical and Biochemical Engineering
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
- P. R. China
| | - Qingbiao Li
- Department of Chemical and Biochemical Engineering
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
- P. R. China
| | - You-Im Chang
- Department of Chemical and Material Engineering
- Tunghai University
- Taichung 40704
- Taiwan
| | - Chuan-Jian Zhong
- Department of Chemistry
- State University of New York at Binghamton
- Binghamton
- USA
| | - Ning He
- Department of Chemical and Biochemical Engineering
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
- P. R. China
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36
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van Hoogmoed CG, Dijkstra RJB, van der Mei HC, Busscher HJ. Influence of Biosurfactant on Interactive Forces between Mutans Streptococci and Enamel Measured by Atomic Force Microscopy. J Dent Res 2016; 85:54-8. [PMID: 16373681 DOI: 10.1177/154405910608500109] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Although interactive forces, influenced by environmental conditions, between oral bacteria and tooth surfaces are important for the development of plaque, they have never been estimated. It is hypothesized that interactive forces, as measured by atomic force microscopy, between enamel with or without a pellicle and two strains of mutans streptococci become less attractive by the application of a Streptococcus mitis BMS biosurfactant coating. Upon approach of each of the strains toward bare and pellicle-coated enamel, adsorbed biosurfactant increased the range of the repulsive forces. Upon retraction of the enamel surface, small adhesion forces (0.8–0.9 nN) were measured for bare enamel that almost disappeared after biosurfactant coating. The prevalence and magnitude of the adhesion forces also decreased upon pellicle-coating of the enamel, with a minor effect of adsorbed biosurfactant. These findings indicate that adsorbed S. mitis BMS biosurfactant changes the interactive forces between the mutans streptococci studied and enamel, explaining the effects of biosurfactant on adhesion.
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Affiliation(s)
- C G van Hoogmoed
- Department of Biomedical Engineering, University Medical Centre Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands.
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37
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Kundukad B, Seviour T, Liang Y, Rice SA, Kjelleberg S, Doyle PS. Mechanical properties of the superficial biofilm layer determine the architecture of biofilms. SOFT MATTER 2016; 12:5718-26. [PMID: 27273453 DOI: 10.1039/c6sm00687f] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Cells in biofilms sense and interact with their environment through the extracellular matrix. The physicochemical properties of the matrix, particularly at the biofilm-environment interface, determine how cells respond to changing conditions. In this study we describe the application of atomic force microscopy and confocal imaging to probe in situ the mechanical properties of these interfacial regions and to elucidate how key matrix components can contribute to the physical sensing by the cells. We describe how the Young's modulus of microcolonies differs according to the size and morphology of microcolonies, as well as the flow rate. The Young's modulus increased as a function of microcolony diameter, which was correlated with the production of the polysaccharide Psl at later stages of maturation for hemispherical or mushroom shaped microcolonies. The Young's modulus of the periphery of the biofilm colony was however independent of the hydrodynamic shear. The morphology of the microcolonies also influenced interfacial or peripheral stiffness. Microcolonies with a diffuse morphology had a lower Young's modulus than isolated, circular ones and this phenomenon was due to a deficiency of Psl. In this way, changes in the specific polysaccharide components imbue the biofilm with distinct physical properties that may modulate the way in which bacteria perceive or respond to their environment. Further, the physical properties of the polysaccharides are closely linked to the specific architectures formed by the developing biofilm.
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Affiliation(s)
- Binu Kundukad
- BioSystems and Micromechanics (BioSym) IRG, Singapore MIT Alliance for Research and Technology (SMART), Singapore
| | - Thomas Seviour
- Singapore Centre on Environmental Life Sciences Engineering, Nanyang Technological University, Singapore
| | - Yang Liang
- Singapore Centre on Environmental Life Sciences Engineering, Nanyang Technological University, Singapore and School of Biological Sciences, Nanyang Technological University, Singapore
| | - Scott A Rice
- Singapore Centre on Environmental Life Sciences Engineering, Nanyang Technological University, Singapore and School of Biological Sciences, Nanyang Technological University, Singapore and Centre for Marine Bio-Innovation and School of Biotechnology and Biomolecular Science, University of New South Wales, Sydney, NSW, Australia
| | - Staffan Kjelleberg
- Singapore Centre on Environmental Life Sciences Engineering, Nanyang Technological University, Singapore and School of Biological Sciences, Nanyang Technological University, Singapore and Centre for Marine Bio-Innovation and School of Biotechnology and Biomolecular Science, University of New South Wales, Sydney, NSW, Australia
| | - Patrick S Doyle
- BioSystems and Micromechanics (BioSym) IRG, Singapore MIT Alliance for Research and Technology (SMART), Singapore and Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
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38
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Mahalik JP, Yang Y, Deodhar C, Ankner JF, Lokitz BS, Kilbey SM, Sumpter BG, Kumar R. Monomer volume fraction profiles in pH responsive planar polyelectrolyte brushes. ACTA ACUST UNITED AC 2016. [DOI: 10.1002/polb.24008] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- J. P. Mahalik
- Computer Science and Mathematics Division; Oak Ridge National Laboratory; Oak Ridge Tennessee 37831
- Center for Nanophase Materials Sciences; Oak Ridge National Laboratory; Oak Ridge Tennessee 37831
| | - Yubo Yang
- Denison University; Granville Ohio 43023
| | - Chaitra Deodhar
- Department of Chemistry; University of Tennessee; Knoxville Tennessee 37996
| | - John F. Ankner
- Spallation Neutron Source; Oak Ridge National Laboratory; Oak Ridge Tennessee 37831
| | - Bradley S. Lokitz
- Center for Nanophase Materials Sciences; Oak Ridge National Laboratory; Oak Ridge Tennessee 37831
| | - S. Michael Kilbey
- Department of Chemistry; University of Tennessee; Knoxville Tennessee 37996
| | - Bobby G. Sumpter
- Computer Science and Mathematics Division; Oak Ridge National Laboratory; Oak Ridge Tennessee 37831
- Center for Nanophase Materials Sciences; Oak Ridge National Laboratory; Oak Ridge Tennessee 37831
| | - Rajeev Kumar
- Computer Science and Mathematics Division; Oak Ridge National Laboratory; Oak Ridge Tennessee 37831
- Center for Nanophase Materials Sciences; Oak Ridge National Laboratory; Oak Ridge Tennessee 37831
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39
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Gupta P, Song B, Neto C, Camesano TA. Atomic force microscopy-guided fractionation reveals the influence of cranberry phytochemicals on adhesion of Escherichia coli. Food Funct 2016; 7:2655-66. [DOI: 10.1039/c6fo00109b] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Characterization of cranberry juice fractions for their role in anti-adhesive properties against pathogenicE. coliusing Atomic Force Microscopy (AFM).
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Affiliation(s)
- Prachi Gupta
- Department of Chemical Engineering
- Worcester Polytechnic Institute
- Worcester
- USA
| | - Biqin Song
- Department of Chemistry and Biochemistry
- University of Massachusetts-Dartmouth
- North Dartmouth
- USA
| | - Catherine Neto
- Department of Chemistry and Biochemistry
- University of Massachusetts-Dartmouth
- North Dartmouth
- USA
| | - Terri A. Camesano
- Department of Chemical Engineering
- Worcester Polytechnic Institute
- Worcester
- USA
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40
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Mechanics of Bacterial Cells and Initial Surface Colonisation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 915:245-60. [DOI: 10.1007/978-3-319-32189-9_15] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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41
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Hernando-Pérez M, Cartagena-Rivera AX, Lošdorfer Božič A, Carrillo PJP, San Martín C, Mateu MG, Raman A, Podgornik R, de Pablo PJ. Quantitative nanoscale electrostatics of viruses. NANOSCALE 2015; 7:17289-98. [PMID: 26228582 DOI: 10.1039/c5nr04274g] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Electrostatics is one of the fundamental driving forces of the interaction between biomolecules in solution. In particular, the recognition events between viruses and host cells are dominated by both specific and non-specific interactions and the electric charge of viral particles determines the electrostatic force component of the latter. Here we probe the charge of individual viruses in liquid milieu by measuring the electrostatic force between a viral particle and the Atomic Force Microscope tip. The force spectroscopy data of co-adsorbed ϕ29 bacteriophage proheads and mature virions, adenovirus and minute virus of mice capsids is utilized for obtaining the corresponding density of charge for each virus. The systematic differences of the density of charge between the viral particles are consistent with the theoretical predictions obtained from X-ray structural data. Our results show that the density of charge is a distinguishing characteristic of each virus, depending crucially on the nature of the viral capsid and the presence/absence of the genetic material.
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Affiliation(s)
- M Hernando-Pérez
- Departamento de Física de la Materia Condensada and Condensed Matter Physics Center - IFIMAC, Universidad Autónoma de Madrid, Spain.
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42
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Zhulina EB, Leermakers FAM, Borisov OV. Ideal Mixing in Multicomponent Brushes of Branched Polymers. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b01722] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Ekaterina B. Zhulina
- Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg 199004, Russia
- St. Petersburg National University of Informational Technologies, Mechanics and Optics, St. Petersburg 197101, Russia
| | - Frans A. M. Leermakers
- Laboratory of Physical Chemistry and Colloid Science, Dreijenplein 6, 6703 HB Wageningen, The Netherlands
| | - Oleg V. Borisov
- Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg 199004, Russia
- St. Petersburg National University of Informational Technologies, Mechanics and Optics, St. Petersburg 197101, Russia
- Institut des Sciences Analytiques et de Physico-Chimie pour l’Environnement
et les Matériaux, CNRS, Université de Pau et des Pays de l’Adour UMR 5254, 64053 Pau, France
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43
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Diao M, Nguyen TA, Taran E, Mahler SM, Nguyen AV. Effect of energy source, salt concentration and loading force on colloidal interactions between Acidithiobacillus ferrooxidans cells and mineral surfaces. Colloids Surf B Biointerfaces 2015; 132:271-80. [DOI: 10.1016/j.colsurfb.2015.05.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2015] [Revised: 05/11/2015] [Accepted: 05/14/2015] [Indexed: 11/28/2022]
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Xu W, Ledin PA, Shevchenko VV, Tsukruk VV. Architecture, Assembly, and Emerging Applications of Branched Functional Polyelectrolytes and Poly(ionic liquid)s. ACS APPLIED MATERIALS & INTERFACES 2015; 7:12570-12596. [PMID: 26010902 DOI: 10.1021/acsami.5b01833] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Branched polyelectrolytes with cylindrical brush, dendritic, hyperbranched, grafted, and star architectures bearing ionizable functional groups possess complex and unique assembly behavior in solution at surfaces and interfaces as compared to their linear counterparts. This review summarizes the recent developments in the introduction of various architectures and understanding of the assembly behavior of branched polyelectrolytes with a focus on functional polyelectrolytes and poly(ionic liquid)s with responsive properties. The branched polyelectrolytes and poly(ionic liquid)s interact electrostatically with small molecules, linear polyelectrolytes, or other branched polyelectrolytes to form assemblies of hybrid nanoparticles, multilayer thin films, responsive microcapsules, and ion-conductive membranes. The branched structures lead to unconventional assemblies and complex hierarchical structures with responsive properties as summarized in this review. Finally, we discuss prospectives for emerging applications of branched polyelectrolytes and poly(ionic liquid)s for energy harvesting and storage, controlled delivery, chemical microreactors, adaptive surfaces, and ion-exchange membranes.
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Affiliation(s)
- Weinan Xu
- †School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Petr A Ledin
- †School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Valery V Shevchenko
- ‡Institute of Macromolecular Chemistry, National Academy of Sciences of Ukraine, Kharkovskoe shosse 48, Kiev 02160, Ukraine
| | - Vladimir V Tsukruk
- †School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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Zhulina EB, Leermakers FAM, Borisov OV. Theory of Brushes Formed by Ψ-Shaped Macromolecules at Solid-Liquid Interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:6514-6522. [PMID: 26029884 DOI: 10.1021/acs.langmuir.5b00947] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We present a theoretical analysis targeted to describe the structural properties of brushes formed by Ψ-shaped macromolecules tethered by terminal segment of stem to planar surface while exposing multiple free branches to the surrounding solution. We use an analytical self-consistent field approach based on the strong stretching approximation, and the assumption of Gaussian elasticity for linear chain fragments of the tethered macromolecules. The effect of weak and strong polydispersity of branches is analyzed. In the case of weakly polydisperse macromolecules, variations in length of branches lead to a more uniform polymer density distribution with slight increase in the brush thickness compared to the case of monodisperse chains with the same degree of polymerization. We demonstrate that in contrast to linear chains, strong polydispersity of Ψ-shaped macromolecules does not necessarily lead to strong perturbations in polymer density distribution. In particular, mixed brushes of the so-called "mirror" dendrons (in which number of stem monomers in one component coincides with number of monomers in a branch of the other component, and vice versa) give rise to a unified polymer density distribution with shape independent of the brush composition. The predictions of analytical theory are systematically compared to the results of numerical self-consistent field modeling based on the Scheutjens-Fleer approach.
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Affiliation(s)
- Ekaterina B Zhulina
- †Institute of Macromolecular Compounds of the Russian Academy of Sciences, St. Petersburg, 199004, Russia
- ‡St. Petersburg National University of Informational Technologies, Mechanics and Optics, St. Petersburg, 197101, Russia
| | - Frans A M Leermakers
- §Laboratory of Physical Chemistry and Colloid Science, Dreijenplein 6, 6703 HB Wageningen, The Netherlands
| | - Oleg V Borisov
- †Institute of Macromolecular Compounds of the Russian Academy of Sciences, St. Petersburg, 199004, Russia
- ‡St. Petersburg National University of Informational Technologies, Mechanics and Optics, St. Petersburg, 197101, Russia
- ∥CNRS, Université de Pau et des Pays de l'Adour UMR 5254, Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux, 64053 Pau, France
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46
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Singh G, Bremmell KE, Griesser HJ, Kingshott P. Colloid-probe AFM studies of the interaction forces of proteins adsorbed on colloidal crystals. SOFT MATTER 2015; 11:3188-3197. [PMID: 25758979 DOI: 10.1039/c4sm02669a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In recent years, colloid-probe AFM has been used to measure the direct interaction forces between colloidal particles of different size or surface functionality in aqueous media, as one can study different forces in symmerical systems (i.e., sphere-sphere geometry). The present study investigates the interaction between protein coatings on colloid probes and hydrophilic surfaces decorated with hexagonally close packed single particle layers that are either uncoated or coated with proteins. Controlled solvent evaporation from aqueous suspensions of colloidal particles (coated with or without lysozyme and albumin) produces single layers of close-packed colloidal crystals over large areas on a solid support. The measurements have been carried out in an aqueous medium at different salt concentrations and pH values. The results show changes in the interaction forces as the surface charge of the unmodified or modified particles, and ionic strength or pH of the solution is altered. At high ionic strength or pH, electrostatic interactions are screened, and a strong repulsive force at short separation below 5 nm dominates, suggesting structural changes in the absorbed protein layer on the particles. We also study the force of adhesion, which decreases with an increment in the salt concentration, and the interaction between two different proteins indicating a repulsive interaction on approach and adhesion on retraction.
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Affiliation(s)
- Gurvinder Singh
- Interdisciplinary Nanoscience Centre, Faculty of Science, Aarhus University, Ny Munkegade, Aarhus C 8000, Denmark
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47
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Affiliation(s)
- SeongMin Jeong
- Asia Pacific Center for Theoretical Physics/Department of Physics; POSTECH Pohang Korea
| | - Xin Zhou
- School of Physics; University of Chinese Academy of Sciences; Beijing China)
| | - Ekaterina B. Zhulina
- Institute of Macromolecular Compounds of the Russian Academy of Sciences and ITMO-University; St. Petersburg Russia)
| | - YongSeok Jho
- Asia Pacific Center for Theoretical Physics/Department of Physics; POSTECH Pohang Korea
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Burgain J, Scher J, Francius G, Borges F, Corgneau M, Revol-Junelles A, Cailliez-Grimal C, Gaiani C. Lactic acid bacteria in dairy food: surface characterization and interactions with food matrix components. Adv Colloid Interface Sci 2014; 213:21-35. [PMID: 25277266 DOI: 10.1016/j.cis.2014.09.005] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 08/30/2014] [Accepted: 09/01/2014] [Indexed: 02/07/2023]
Abstract
This review gives an overview of the importance of interactions occurring in dairy matrices between Lactic Acid Bacteria and milk components. Dairy products are important sources of biological active compounds of particular relevance to human health. These compounds include immunoglobulins, whey proteins and peptides, polar lipids, and lactic acid bacteria including probiotics. A better understanding of interactions between bioactive components and their delivery matrix may successfully improve their transport to their target site of action. Pioneering research on probiotic lactic acid bacteria has mainly focused on their host effects. However, very little is known about their interaction with dairy ingredients. Such knowledge could contribute to designing new and more efficient dairy food, and to better understand relationships between milk constituents. The purpose of this review is first to provide an overview of the current knowledge about the biomolecules produced on bacterial surface and the composition of the dairy matter. In order to understand how bacteria interact with dairy molecules, adhesion mechanisms are subsequently reviewed with a special focus on the environmental conditions affecting bacterial adhesion. Methods dedicated to investigate the bacterial surface and to decipher interactions between bacteria and abiotic dairy components are also detailed. Finally, relevant industrial implications of these interactions are presented and discussed.
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Diao M, Taran E, Mahler S, Nguyen AV. A concise review of nanoscopic aspects of bioleaching bacteria-mineral interactions. Adv Colloid Interface Sci 2014; 212:45-63. [PMID: 25245273 DOI: 10.1016/j.cis.2014.08.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 08/01/2014] [Accepted: 08/28/2014] [Indexed: 01/17/2023]
Abstract
Bioleaching is a technology for the recovery of metals from minerals by means of microorganisms, which accelerate the oxidative dissolution of the mineral by regenerating ferric ions. Bioleaching processes take place at the interface of bacteria, sulfide mineral and leaching solution. The fundamental forces between a bioleaching bacterium and mineral surface are central to understanding the intricacies of interfacial phenomena, such as bacterial adhesion or detachment from minerals and the mineral dissolution. This review focuses on the current state of knowledge in the colloidal aspect of bacteria-mineral interactions, particularly for bioleaching bacteria. Special consideration is given to the microscopic structure of bacterial cells and the atomic force microscopy technique used in the quantification of fundamental interaction forces at nanoscale.
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Affiliation(s)
- Mengxue Diao
- School of Chemical Engineering, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Elena Taran
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Stephen Mahler
- School of Chemical Engineering, The University of Queensland, Brisbane, Queensland 4072, Australia; Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Anh V Nguyen
- School of Chemical Engineering, The University of Queensland, Brisbane, Queensland 4072, Australia.
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50
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Sircar S, Younger JG, Bortz DM. Sticky surface: sphere-sphere adhesion dynamics. JOURNAL OF BIOLOGICAL DYNAMICS 2014; 9 Suppl 1:79-89. [PMID: 25159830 PMCID: PMC4344442 DOI: 10.1080/17513758.2014.942394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We present a multi-scale model to study the attachment of spherical particles with a rigid core, coated with binding ligands and suspended in the surrounding, quiescent fluid medium. This class of fluid-immersed adhesion is widespread in many natural and engineering settings, particularly in microbial surface adhesion. Our theory highlights how the micro-scale binding kinetics of these ligands, as well as the attractive/repulsive surface potential in an ionic medium affects the eventual macro-scale size distribution of the particle aggregates (flocs). The bridge between the micro-macro model is made via an aggregation kernel. Results suggest that the presence of elastic ligands on the particle surface lead to the formation of larger floc aggregates via efficient inter-floc collisions (i.e. non-zero sticking probability, g). Strong electrolytic composition of the surrounding fluid favours large floc formation as well. The kernel for the Brownian diffusion for hard spheres is recovered in the limit of perfect binding effectiveness (g→1) and in a neutral solution with no dissolved salts.
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Affiliation(s)
- Sarthok Sircar
- a School of Mathematical Sciences , University of Adelaide , Adelaide , SA 5000 , Australia
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