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Dixit S, Varshney S, Gupta D, Sharma S. Factors affecting biofilm formation by bacteria on fabrics. Int Microbiol 2024; 27:1111-1123. [PMID: 38057457 DOI: 10.1007/s10123-023-00460-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 11/13/2023] [Accepted: 11/17/2023] [Indexed: 12/08/2023]
Abstract
Fabrics act as fomites for microorganisms, thereby playing a significant role in infection transmission, especially in the healthcare and hospitality sectors. This study aimed to examine the biofilm formation ability of four nosocomial infection-causing bacteria (Acinetobacter calcoaceticus, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus) on cotton, polyester, polyester-cotton blend, silk, wool, viscose, and nylon, used frequently in the healthcare sector, by qualitative and quantitative methods. The impact of temperature, pH, and relative humidity (RH) on biofilm formation was also assessed. P. aeruginosa and S. aureus were strong biofilm producers, while E. coli produced weak biofilm. Wool (maximum roughness) showed the highest bacterial load, while silk (lowest roughness) showed the least. P. aeruginosa exhibited a higher load on all fabrics, than other test bacteria. Extracellular polymeric substances were characterized by infrared spectroscopy. Roughness of biofilms was assessed by atomic force microscopy. For biofilm formation, optimum temperature, pH, and RH were 30 °C, 7.0, and 62%, respectively. MgCl2 and CaCl2 were the most effective in removing bacterial biofilm. In conclusion, biofilm formation was observed to be influenced by the type of fabric, bacteria, and environmental conditions. Implementing recommended guidelines for the effective disinfection of fabrics is crucial to curb the risk of nosocomial infections. In addition, designing modified healthcare fabrics that inhibit pathogen load could be an effective method to mitigate the transmission of infections.
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Affiliation(s)
- Shweta Dixit
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi, 110016, India
| | - Swati Varshney
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi, 110016, India
- Present address: Department of Biochemistry, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Deepti Gupta
- Department of Textile and Fibre Engineering, Indian Institute of Technology Delhi, New Delhi, 110016, India
| | - Shilpi Sharma
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi, 110016, India.
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2
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Mu M, Liu S, DeFlorio W, Hao L, Wang X, Salazar KS, Taylor M, Castillo A, Cisneros-Zevallos L, Oh JK, Min Y, Akbulut M. Influence of Surface Roughness, Nanostructure, and Wetting on Bacterial Adhesion. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:5426-5439. [PMID: 37014907 PMCID: PMC10848269 DOI: 10.1021/acs.langmuir.3c00091] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 03/22/2023] [Indexed: 05/11/2023]
Abstract
Bacterial fouling is a persistent problem causing the deterioration and failure of functional surfaces for industrial equipment/components; numerous human, animal, and plant infections/diseases; and energy waste due to the inefficiencies at internal and external geometries of transport systems. This work gains new insights into the effect of surface roughness on bacterial fouling by systematically studying bacterial adhesion on model hydrophobic (methyl-terminated) surfaces with roughness scales spanning from ∼2 nm to ∼390 nm. Additionally, a surface energy integration framework is developed to elucidate the role of surface roughness on the energetics of bacteria and substrate interactions. For a given bacteria type and surface chemistry; the extent of bacterial fouling was found to demonstrate up to a 75-fold variation with surface roughness. For the cases showing hydrophobic wetting behavior, both increased effective surface area with increasing roughness and decreased activation energy with increased surface roughness was concluded to enhance the extent of bacterial adhesion. For the cases of superhydrophobic surfaces, the combination of factors including (i) the surpassing of Laplace pressure force of interstitial air over bacterial adhesive force, (ii) the reduced effective substrate area for bacteria wall due to air gaps to have direct/solid contact, and (iii) the reduction of attractive van der Waals force that holds adhering bacteria on the substrate were summarized to weaken the bacterial adhesion. Overall, this study is significant in the context of designing antifouling coatings and systems as well as explaining variations in bacterial contamination and biofilm formation processes on functional surfaces.
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Affiliation(s)
- Minchen Mu
- Artie
McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843, United States
| | - Shuhao Liu
- Artie
McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843, United States
| | - William DeFlorio
- Artie
McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843, United States
| | - Li Hao
- School
of Chemistry and Chemical Engineering, Zhongkai
University of Agriculture and Engineering, Guangzhou, Guangdong 510225, P. R. China
| | - Xunhao Wang
- Department
of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
| | - Karla Solis Salazar
- Department
of Food Science and Technology, Texas A&M
University, College Station, Texas 77843, United States
| | - Matthew Taylor
- Department
of Food Science and Technology, Texas A&M
University, College Station, Texas 77843, United States
| | - Alejandro Castillo
- Department
of Food Science and Technology, Texas A&M
University, College Station, Texas 77843, United States
| | - Luis Cisneros-Zevallos
- Department
of Horticultural Sciences, Texas A&M
University, College Station, Texas 77843, United States
| | - Jun Kyun Oh
- Department
of Polymer Science and Engineering, Dankook
University, 152 Jukjeon-ro, Suji-gu, Yongin-si, Gyeonggi-do 16890, Republic of Korea
| | - Younjin Min
- Department
of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
| | - Mustafa Akbulut
- Artie
McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843, United States
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3
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Yu T, Fu Y, He J, Zhang J, Xianyu Y. Identification of Antibiotic Resistance in ESKAPE Pathogens through Plasmonic Nanosensors and Machine Learning. ACS NANO 2023; 17:4551-4563. [PMID: 36867448 DOI: 10.1021/acsnano.2c10584] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Antibiotic-resistant ESKAPE pathogens cause nosocomial infections that lead to huge morbidity and mortality worldwide. Rapid identification of antibiotic resistance is vital for the prevention and control of nosocomial infections. However, current techniques like genotype identification and antibiotic susceptibility testing are generally time-consuming and require large-scale equipment. Herein, we develop a rapid, facile, and sensitive technique to determine the antibiotic resistance phenotype among ESKAPE pathogens through plasmonic nanosensors and machine learning. Key to this technique is the plasmonic sensor array that contains gold nanoparticles functionalized with peptides differing in hydrophobicity and surface charge. The plasmonic nanosensors can interact with pathogens to generate bacterial fingerprints that alter the surface plasmon resonance (SPR) spectra of nanoparticles. In combination with machine learning, it enables the identification of antibiotic resistance among 12 ESKAPE pathogens in less than 20 min with an overall accuracy of 89.74%. This machine-learning-based approach allows for the identification of antibiotic-resistant pathogens from patients and holds great promise as a clinical tool for biomedical diagnosis.
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Affiliation(s)
- Ting Yu
- State Key Laboratory of Fluid Power and Mechatronic Systems, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, People's Republic of China
| | - Ying Fu
- Key Laboratory of Precision Medicine in Diagnosis and Monitoring Research of Zhejiang Province, Sir Run Run Shaw Hospital, Zhejiang University, Hangzhou 310016, People's Republic of China
| | - Jintao He
- College of Animal Sciences, Zhejiang University, Hangzhou 310058, People's Republic of China
| | - Jun Zhang
- Key Laboratory of Precision Medicine in Diagnosis and Monitoring Research of Zhejiang Province, Sir Run Run Shaw Hospital, Zhejiang University, Hangzhou 310016, People's Republic of China
| | - Yunlei Xianyu
- State Key Laboratory of Fluid Power and Mechatronic Systems, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, People's Republic of China
- Key Laboratory of Precision Medicine in Diagnosis and Monitoring Research of Zhejiang Province, Sir Run Run Shaw Hospital, Zhejiang University, Hangzhou 310016, People's Republic of China
- Future Food Laboratory, Innovation Center of Yangtze River Delta, Zhejiang University, Jiaxing 314100, People's Republic of China
- Ningbo Research Institute, Zhejiang University, Ningbo 315100, People's Republic of China
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4
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Jose NM, Bunt CR, McDowell A, Chiu JZS, Hussain MA. Short communication: A study of Lactobacillus isolates' adherence to and influence on membrane integrity of human Caco-2 cells. J Dairy Sci 2017; 100:7891-7896. [PMID: 28822542 DOI: 10.3168/jds.2017-12912] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 07/06/2017] [Indexed: 01/03/2023]
Abstract
The selection criteria of ideal probiotic bacteria are complex and involve many factors. One key criterion is based on the ability of the probiotic bacteria to adhere to the epithelial lining of the gastrointestinal tract. The objective of this study was to evaluate and compare the adherence and influence on membrane integrity of 2 selected lactobacilli isolates-Lactobacillus rhamnosus MI13 (dairy food origin) and L. plantarum RC2 (bovine rumen origin)-to Caco-2 cells in the presence and absence of Escherichia coli. The adhesion and influence on membrane integrity properties of the 2 Lactobacillus isolates were compared with Escherichia coli, a human commensal bacterium. From the adhesion studies, we concluded that the bovine rumen isolate exhibited better adherence to Caco-2 cells than the dairy food isolate. In contrast, the dairy food isolate better protected the Caco-2 monolayer from damage induced by ethanol.
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Affiliation(s)
- Neethu M Jose
- Department of Wine, Food and Molecular Biosciences, Lincoln University, Lincoln 7647, New Zealand
| | - Craig R Bunt
- Department of Agriculture, Lincoln University, Lincoln 7647, New Zealand.
| | - Arlene McDowell
- School of Pharmacy, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Jasper Z S Chiu
- School of Pharmacy, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Malik A Hussain
- Department of Wine, Food and Molecular Biosciences, Lincoln University, Lincoln 7647, New Zealand.
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White CP, Popovici J, Lytle DA, Rice EW. Endospore surface properties of commonly used Bacillus anthracis surrogates vary in aqueous solution. Antonie van Leeuwenhoek 2014; 106:243-51. [PMID: 24817579 DOI: 10.1007/s10482-014-0187-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 04/23/2014] [Indexed: 10/25/2022]
Abstract
The hydrophobic character and electrophoretic mobility (EPM) of microorganisms are vital aspects of understanding their interactions with the environment. These properties are fundamental in fate-and-transport, physiological, and virulence studies, and thus integral in surrogate selection. Hydrophobic and electrostatic forces are significant contributors to particle and microorganism mobility in the environment. Herein, the surface properties of commonly used Bacillus anthracis surrogate endospores were tested under comparable conditions with respect to culture, endospore purification, buffer type and strength. Additionally, data is presented of endospores suspended in dechlorinated tap water to evaluate the surrogates in regard to a breach of water infrastructure security. The surface properties of B. anthracis were found to be the most hydrophobic and least electronegative among the six Bacillus species tested across buffer strength. The effect of EPM on hydrophobicity varies in a species-specific manner. This study demonstrates that surrogate surface properties differ and care must be taken when choosing the most suitable surrogate. Moreover, it is shown that Bacillus thuringensis best represents Bacillus anthracis-Sterne with respect to both EPM and hydrophobicity across all test buffers.
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Affiliation(s)
- Colin P White
- Pegasus Technical Services Inc., Cincinnati, OH, 45219, USA,
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6
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Rühs P, Böcker L, Inglis R, Fischer P. Studying bacterial hydrophobicity and biofilm formation at liquid–liquid interfaces through interfacial rheology and pendant drop tensiometry. Colloids Surf B Biointerfaces 2014; 117:174-84. [DOI: 10.1016/j.colsurfb.2014.02.023] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 02/06/2014] [Accepted: 02/12/2014] [Indexed: 12/17/2022]
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7
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Suriyarak S, Gibis M, Schmidt H, Villeneuve P, Weiss J. Antimicrobial mechanism and activity of dodecyl rosmarinate against Staphylococcus carnosus LTH1502 as influenced by addition of salt and change in pH. J Food Prot 2014; 77:444-52. [PMID: 24674436 DOI: 10.4315/0362-028x.jfp-13-239] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Antimicrobial activity and mechanism of action of rosmarinic acid (RA) and dodecyl rosmarinate (RE12) against Staphylococcus carnosus LTH1502 were studied as a function of pH (5.8 to 7.2) and in the presence of salts (KCl and MgCl2, 0 to 500 mM). Microbial cultures were exposed to unesterified RA and to esterified RE12, and cell number was determined by plate counting. Cells exposed to RA and RE12 at the minimum bactericidal concentration (200 and 0.05 mM, respectively) were examined using scanning electron microscopy to observe potential morphological changes. Activity of RA was found to be strongly dependent on pH, salt type, and concentration, whereas RE12 led to the compound's activity becoming independent of pH, salt concentration, and type. Scanning electron microscopy images showed that morphology of cells treated with RE12 after incubation of 1 h was irrevocably altered. Our results suggest that esterification (i) altered the mechanism of action by increasing the compound's affinity for cell membranes and (ii) decreased the compound's susceptibility to changes in environmental conditions that alter its charge. Highly specific changes in structure-activity relationships can be observed when esterifying a naturally active phenol such as RA with an alkyl chain that has a carbon chain length of 12.
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Affiliation(s)
- Sarisa Suriyarak
- Department of Food Physics and Meat Science, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 21/25, 70599 Stuttgart, Germany
| | - Monika Gibis
- Department of Food Physics and Meat Science, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 21/25, 70599 Stuttgart, Germany
| | - Herbert Schmidt
- Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), Unité Mixte de Recherche (UMR), Ingénierie des Agropolymères et Technologies Émergentes (IATE), Montpellier, 34060 France
| | - Pierre Villeneuve
- Department of Food Microbiology, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 28, 70599 Stuttgart, Germany
| | - Jochen Weiss
- Department of Food Physics and Meat Science, Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstrasse 21/25, 70599 Stuttgart, Germany.
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8
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Surface hydrophobicity of petroleum hydrocarbon degrading Burkholderia strains and their interactions with NAPLs and surfaces. Colloids Surf B Biointerfaces 2010; 78:101-8. [PMID: 20236810 DOI: 10.1016/j.colsurfb.2010.02.019] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Revised: 02/17/2010] [Accepted: 02/17/2010] [Indexed: 11/23/2022]
Abstract
Bacterial cell surface hydrophobicity (CSH) is an important factor governing the growth and adhesion behavior of microorganisms on non-aqueous phase liquids (NAPLs). In this work CSH and surface charge was quantified for three oil degrading Burkholderia cultures: aliphatic degrader Burkholderia cepacia (ES1) and two strains of aromatic degrading Burkholderia multivorans (NG1 and HN1) based on contact angle and zeta potential measurement. Model non-aqueous phase liquids (NAPLs) were formulated using n-hexadecane, naphthalene, phenanthrene and pyrene in varying concentration. Adhesion on to glass surfaces of varying hydrophobicity and adherence to n-hexadecane was quantified and correlated with hydrophobicity of the surface; variation in CSH of the culture in response to model NAPL used as growth substrate; and variation in zeta potential as a result of variation in growth substrate, ionic strength and pH of resuspension solution. B. cepacia (ES1) and B. multivorans (HN1) depicted comparable CSH which was higher than that of B. multivorans (NG1). For each culture, CSH was found to vary with the model NAPL used as growth substrate. Adhesion to glass increased with increase in CSH of the bacterial culture and with increase in hydrophobicity of the glass surface. B. cepacia (ES1) with lower negative zeta potential consistently depicted greater adhesion compared to B. multivorans (HN1). Adherence to n-hexadecane was significantly affected by various other factors, such as, growth substrate, pH, resuspension solution and their interactions as revealed through statistical analysis. These factors affected both the zeta potential and adherence to n-hexadecane to varying degree for the three Burkholderia cultures.
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9
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Speranza G, Gottardi G, Pederzolli C, Lunelli L, Canteri R, Pasquardini L, Carli E, Lui A, Maniglio D, Brugnara M, Anderle M. Role of chemical interactions in bacterial adhesion to polymer surfaces. Biomaterials 2004; 25:2029-37. [PMID: 14741617 DOI: 10.1016/j.biomaterials.2003.08.061] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Development of biomaterial-related infections is attracting an increasing interest due to the significant percentage of implant failure in the hospital care. Recent literature puts in evidence the dependence of the infection risk on the different biomaterials used, because of the different interactions between material surface and micro-organisms. Despite this, the mechanisms underlying the adhesion of bacteria to the biomaterial surface are still unclear. Aim of this work is to study the initial events of the processes responsible for the bacterial adhesion on polymers in order to prevent the development of bacterial infections and the consequent failure and replacement of biomedical devices. Electrostatic and Lifshitz-van der Waals forces are usually considered responsible for the interactions at the biomaterial interface. A new term that involves Lewis acid-base interactions is here introduced to better describe the bacterial adhesion to the polymer surface. Two requirements are needed to test this hypothesis: the development of an ideal polymeric surface in terms of chemical and morphological properties and the choice of a specific bacterial strain to be utilized as "probe". Experiments were worked out using an Escherichia coli (Gram-) strain that represent one of the principal isolates from infected biomaterial implants and its adhesion was investigated on polymers having different acid/basic character. The findings indicate that the bacterial adhesion is influenced by the chemical properties of the polymeric surface. These results may be interpreted taking into account a mechanism in which the acid/base (Lewis) interaction plays an important role.
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Affiliation(s)
- G Speranza
- ITC-IRST, Centro per la Ricerca Scientifica e Tecnologica, Sommarive str 18, 38050 Povo, Trento, Italy.
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Hayashi H, Tsuneda S, Hirata A, Sasaki H. Soft particle analysis of bacterial cells and its interpretation of cell adhesion behaviors in terms of DLVO theory. Colloids Surf B Biointerfaces 2001; 22:149-157. [PMID: 11451661 DOI: 10.1016/s0927-7765(01)00161-8] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The electrokinetic properties of two nitrifying strains, Nitrosomonas europaea and Nitrobacter winogradskyi, and three heterotrophic bacteria, Escherichia coli, Pseudomonas putida and Pseudomonas aeruginosa, were examined by electrophoretic mobility measurement and analyzed using the soft particle electrophoresis theory that is suitable for biological particles. The bacterial adhesion characteristics onto glass bead substratum were also evaluated by packed bed method. The mobility of the bacterial cells employed converged to a non-zero value as the ionic concentration increased, suggesting that the bacterial cells exhibited typical soft particle characteristics. Moreover, cell surface potentials based on the soft particle theory were lower than those estimated by the conventional Smoluchowski formula, i.e. zeta potential. Cell collision efficiencies onto glass beads (alpha(0)) were largely dependent on interfacial interaction, although almost electrically neutral P. aeruginosa did not follow that trend. From a comparison of alpha(0) with DLVO interaction energy maximum (V(max)), it was assumed that heterocoagulation between cell and substratum at primary minimum potential took place under V(max) of 24-34 kT based on soft particle analysis. On the other hand, V(max) predictions using the Smoluchowski theory gave 81-223 kT, which indicated the possibility of overestimating electrostatic repulsive forces by the conventional Smoluchowski theory. Thus, the application of this new electrophoresis theory to several kinds of bacterial cells has led to the revision of the interpretation of bacterial mobility data and provided a more detailed understanding of the bacterial adhesion phenomenon.
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Affiliation(s)
- H Hayashi
- Department of Chemical Engineering, School of Science and Engineering, Waseda University, Ohkubo 3-4-1, Shinjuku-ku, 169-8555, Tokyo, Japan
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11
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Pembrey RS, Marshall KC, Schneider RP. Cell surface analysis techniques: What do cell preparation protocols do to cell surface properties? Appl Environ Microbiol 1999; 65:2877-94. [PMID: 10388679 PMCID: PMC91432 DOI: 10.1128/aem.65.7.2877-2894.1999] [Citation(s) in RCA: 158] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/1998] [Accepted: 03/31/1999] [Indexed: 11/20/2022] Open
Abstract
Cell surface analysis often requires manipulation of cells prior to examination. The most commonly employed procedures are centrifugation at different speeds, changes of media during washing or final resuspension, desiccation (either air drying for contact angle measurements or freeze-drying for sensitive spectroscopic analysis, such as X-ray photoelectron spectroscopy), and contact with hydrocarbon (hydrophobicity assays). The effects of these procedures on electrophoretic mobility, adhesion to solid substrata, affinity to a number of Sepharose columns, structural integrity, and cell viability were systematically investigated for a range of model organisms, including carbon- and nitrogen-limited Psychrobacter sp. strain SW8 (glycocalyx-bearing cells), Escherichia coli (gram-negative cells without a glycocalyx), and Staphylococcus epidermidis (gram-positive cells without a glycocalyx). All of the cell manipulation procedures severely modified the physicochemical properties of cells, but with each procedure some organisms were more susceptible than others. Considerable disruption of cell surfaces occurred when organisms were placed in contact with a hydrocarbon (hexadecane). The majority of cells became nonculturable after air drying and freeze-drying. Centrifugation at a high speed (15,000 x g) modified many cell surface parameters significantly, although cell viability was considerably affected only in E. coli. The type of washing or resuspension medium had a strong influence on the values of cell surface parameters, particularly when high-salt solutions were compared with low-salt buffers. The values for parameters obtained with different methods that allegedly measure similar cell surface properties did not correlate for most cells. These results demonstrate that the methods used to prepare cells for cell surface analysis need to be critically investigated for each microorganism so that the final results obtained reflect the nature of the in situ microbial cell surface as closely as possible. There is an urgent need for new, reliable, nondestructive, minimally manipulative cell surface analysis techniques that can be used in situ.
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Affiliation(s)
- R S Pembrey
- School of Microbiology and Immunology, University of New South Wales, Sydney, 2052, Australia
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12
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Bunt CR, Jones DS, Tucker IG. The effects of pH, ionic strength and polyvalent ions on the cell surface hydrophobicity of Escherichia coli evaluated by the BATH and HIC methods. Int J Pharm 1995. [DOI: 10.1016/0378-5173(94)00205-j] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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