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Millan-Solsona R, Brown SR, Zhang L, Madugula SS, Zhao H, Dumerer B, Bible AN, Lavrik NV, Vasudevan RK, Biswas A, Morrell-Falvey JL, Retterer S, Checa M, Collins L. Analysis of biofilm assembly by large area automated AFM. NPJ Biofilms Microbiomes 2025; 11:75. [PMID: 40341406 PMCID: PMC12062311 DOI: 10.1038/s41522-025-00704-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2024] [Accepted: 04/12/2025] [Indexed: 05/10/2025] Open
Abstract
Biofilms are complex microbial communities critical in medical, industrial, and environmental contexts. Understanding their assembly, structure, genetic regulation, interspecies interactions, and environmental responses is key to developing effective control and mitigation strategies. While atomic force microscopy (AFM) offers critically important high-resolution insights on structural and functional properties at the cellular and even sub-cellular level, its limited scan range and labor-intensive nature restricts the ability to link these smaller scale features to the functional macroscale organization of the films. We begin to address this limitation by introducing an automated large area AFM approach capable of capturing high-resolution images over millimeter-scale areas, aided by machine learning for seamless image stitching, cell detection, and classification. Large area AFM is shown to provide a very detailed view of spatial heterogeneity and cellular morphology during the early stages of biofilm formation which were previously obscured. Using this approach, we examined the organization of Pantoea sp. YR343 on PFOTS-treated glass surfaces. Our findings reveal a preferred cellular orientation among surface-attached cells, forming a distinctive honeycomb pattern. Detailed mapping of flagella interactions suggests that flagellar coordination plays a role in biofilm assembly beyond initial attachment. Additionally, we use large-area AFM to characterize surface modifications on silicon substrates, observing a significant reduction in bacterial density. This highlights the potential of this method for studying surface modifications to better understand and control bacterial adhesion and biofilm formation.
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Affiliation(s)
- Ruben Millan-Solsona
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
| | - Spenser R Brown
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Lance Zhang
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Sita Sirisha Madugula
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - HuanHuan Zhao
- Bredesen Center for Interdisciplinary Research, University of Tennessee, Knoxville, USA
| | - Blythe Dumerer
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Amber N Bible
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Nickolay V Lavrik
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Rama K Vasudevan
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Arpan Biswas
- University of Tennessee-Oak Ridge Innovation Institute, Knoxville, TN, 37996, USA
| | | | - Scott Retterer
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Martí Checa
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Liam Collins
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
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Sonu PK, Srivastav AK, Anjali, Peddireddy V, Kumar U. Extraction and physiochemical characterization of micro-fibrillated cellulose based composite biofilm derived from Aegle marmelos fruit shells waste for packaging applications supported by in-silico docking studies. Int J Biol Macromol 2025; 309:142921. [PMID: 40210077 DOI: 10.1016/j.ijbiomac.2025.142921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2024] [Revised: 03/27/2025] [Accepted: 04/06/2025] [Indexed: 04/12/2025]
Abstract
The utilization of waste shells from Aegle marmelos (bael) as a source of Micro fibrillated cellulose (MFC) was undertaken for applications in food packaging within the framework of this investigation. FTIR analysis of CAM and Raw Aegle marmelos shell powder (RAM) showed stretching of -OH and -CH groups at 3339 cm-1 and 2889 cm-1. Our results showed that crystallinity indices of CAM and RAM were 39.59 % and 18.89 %, respectively indicating a significant raise in crystallinity after extraction. FTIR analysis reveals the presence of hydroxyl groups (3306 cm-1) in all films. Exploration of the results indicated the development of covalent and H (hydrogen) bonds between CAM and Guar gum/Chitosan (GT), as discerned through FT-IR studies. X-ray diffraction unveiled in the amorphous feature of the films following CAM into GT composite film. Evaluation through FE-SEM exhibited a densely disordered network contributing to a heightened contact angle of the resultant film with an enhanced concentration of CAM. Cellulose Iβ and Chitosan showed stronger binding affinity of -7.3 kcal/mol, suggesting greater compatibility and stability. The antioxidant capacity of the films increased from 10.90 to 61.80 due to addition of CAM in the GT mixture where elevated concentrations demonstrated better scavenging activity.
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Affiliation(s)
- Prince Kumar Sonu
- Department of Nutrition Biology, School of Interdisciplinary & Applied Sciences, Central University of Haryana, Jant-Pali, Mahendergarh, Haryana 12031, India
| | - Amit Kumar Srivastav
- Department of Microbiology, Biochemistry, and Immunology, Morehouse School of Medicine, Atlanta, GA 30310, USA
| | - Anjali
- Department of Nutrition Biology, School of Interdisciplinary & Applied Sciences, Central University of Haryana, Jant-Pali, Mahendergarh, Haryana 12031, India
| | - Vidyullatha Peddireddy
- Department of Nutrition Biology, School of Interdisciplinary & Applied Sciences, Central University of Haryana, Jant-Pali, Mahendergarh, Haryana 12031, India.
| | - Umesh Kumar
- Department of Nutrition Biology, School of Interdisciplinary & Applied Sciences, Central University of Haryana, Jant-Pali, Mahendergarh, Haryana 12031, India.
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Nakamura N, Yamagishi T, Nagata W, Akahane Y, Seo H, Otsuka A, Hishikawa D, Yoshimoto R, Miyamae N, Ohta S. Systematic study on the evaluation method of surface antibacterial activity based on the fluorescent observation of bacterial growth. Sci Rep 2025; 15:1124. [PMID: 39890805 PMCID: PMC11785733 DOI: 10.1038/s41598-024-81945-3] [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: 05/31/2024] [Accepted: 12/02/2024] [Indexed: 02/03/2025] Open
Abstract
Antibacterial and antiviral coating materials have attracted increasing attention for the prevention of infections caused by frequently touched surfaces in communities and hospitals. The standard assessment procedure for antibacterial surfaces involves bacterial culture on a film-covered substrate followed by transfer onto agar for colony counting (ISO22196:2011). However, this assessment lacks temporal and spatial information regarding bacterial growth, resulting in an incomplete and inaccurate evaluation of the antibacterial activity of the surface. In this study, we develop a novel evaluation procedure for antibacterial substrates that enables in situ visualization of bacterial growth on a surface with centimeter-scale spatial information using fluorescent protein-expressing bacterial cells and an image acquisition setup. The effects of equipment parameters on bacterial growth are systematically investigated to establish the standard evaluation conditions. Based on the optimized parameters, a quantitative evaluation of the antibacterial activity of the coating material is successfully demonstrated. The proposed method is expected to be useful in investigating the spatial and temporal distribution of bacterial growth on substrates.
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Affiliation(s)
- Noriko Nakamura
- Institute of Engineering Innovation, University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo, 113-8656, Japan
- Department of Bioengineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113- 8656, Japan
- Department of Chemical System Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Tatsuki Yamagishi
- Department of Bioengineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113- 8656, Japan
| | - Wataru Nagata
- Department of Chemical System Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Yuki Akahane
- Department of Chemical System Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Hyemin Seo
- Department of Bioengineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113- 8656, Japan
| | - Ayaka Otsuka
- Department of Bioengineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113- 8656, Japan
| | - Daiki Hishikawa
- Nippon Paint Co., Ltd, 4-1-15 Minamishinagawa, Shinagawa-ku, Tokyo, 140-8675, Japan
| | - Risa Yoshimoto
- Nippon Paint Co., Ltd, 4-1-15 Minamishinagawa, Shinagawa-ku, Tokyo, 140-8675, Japan
| | - Nobuhiro Miyamae
- Nippon Paint Co., Ltd, 4-1-15 Minamishinagawa, Shinagawa-ku, Tokyo, 140-8675, Japan
| | - Seiichi Ohta
- Institute of Engineering Innovation, University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo, 113-8656, Japan.
- Department of Bioengineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113- 8656, Japan.
- Department of Chemical System Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
- Precursor Research for Embryonic Science (PRESTO), Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi-shi, Saitama, 332-0012, Japan.
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Bitalac JMS, Lantican NB, Gomez NCF, Onda DFL. Attachment of potential cultivable primo-colonizing bacteria and its implications on the fate of low-density polyethylene (LDPE) plastics in the marine environment. JOURNAL OF HAZARDOUS MATERIALS 2023; 451:131124. [PMID: 36871466 DOI: 10.1016/j.jhazmat.2023.131124] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 02/27/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
Plastics released in the environment become suitable matrices for microbial attachment and colonization. Plastics-associated microbial communities interact with each other and are metabolically distinct from the surrounding environment. However, pioneer colonizing species and their interaction with the plastic during initial colonization are less described. Marine sediment bacteria from sites in Manila Bay were isolated via a double selective enrichment method using sterilized low-density polyethylene (LDPE) sheets as the sole carbon source. Ten isolates were identified to belong to the genera Halomonas, Bacillus, Alteromonas, Photobacterium, and Aliishimia based on 16S rRNA gene phylogeny, and majority of the taxa found exhibit a surface-associated lifestyle. Isolates were then tested for their ability to colonize polyethylene (PE) through co-incubation with LDPE sheets for 60 days. Growth of colonies in crevices, formation of cell-shaped pits, and increased roughness of the surface indicate physical deterioration. Fourier-transform infrared (FT-IR) spectroscopy revealed significant changes in the functional groups and bond indices on LDPE sheets separately co-incubated with the isolates, demonstrating that different species potentially target different substrates of the photo-oxidized polymer backbone. Understanding the activity of primo-colonizing bacteria on the plastic surface can provide insights on the possible mechanisms used to make plastic more bioavailable for other species, and their implications on the fate of plastics in the marine environment.
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Affiliation(s)
- Justine Marey S Bitalac
- The Marine Science Institute, University of the Philippines Diliman, 1101 Quezon City, Philippines; Microbiology Division, Institute of Biological Sciences, College of Arts and Sciences, University of the Philippines Los Baños, 4031 Laguna, Philippines
| | - Nacita B Lantican
- Microbiology Division, Institute of Biological Sciences, College of Arts and Sciences, University of the Philippines Los Baños, 4031 Laguna, Philippines
| | - Norchel Corcia F Gomez
- The Marine Science Institute, University of the Philippines Diliman, 1101 Quezon City, Philippines; Microbiology Division, Institute of Biological Sciences, College of Arts and Sciences, University of the Philippines Los Baños, 4031 Laguna, Philippines
| | - Deo Florence L Onda
- The Marine Science Institute, University of the Philippines Diliman, 1101 Quezon City, Philippines.
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van Dun SCJ, Verheul M, Pijls BGCW, van Prehn J, Scheper H, Galli F, Nibbering PH, de Boer MGJ. Influence of surface characteristics of implant materials on MRSA biofilm formation and effects of antimicrobial treatment. Front Microbiol 2023; 14:1145210. [PMID: 37152752 PMCID: PMC10159048 DOI: 10.3389/fmicb.2023.1145210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Accepted: 04/03/2023] [Indexed: 05/09/2023] Open
Abstract
Introduction One of the main causes of treatment failure in bacterial prosthetic joint infections (PJI) is biofilm formation. The topography of the biofilm may be associated with susceptibility to antimicrobial treatment. The aims of this study were to assess differences in topography of biofilms on different implant materials and the correlation thereof with susceptibility to antimicrobial treatment. Methods Methicillin-resistant Staphylococcus aureus (MRSA) 7-day mature biofilms were generated on disks made from titanium alloys (Ti-6Al-7Nb and Ti-6Al-4V), synthetic polymer and orthopedic bone cement, commonly used in implant surgery. The surface topography of these implant materials and the biofilms cultured on them was assessed using atomic force microscopy. This provided detailed images, as well as average roughness (Ra) and peak-to-valley roughness (Rt) values in nanometers, of the biofilm and the material surfaces. Bacterial counts within biofilms were assessed microbiologically. Antimicrobial treatment of biofilms was performed by 24-h exposure to the combination of rifampicin and ciprofloxacin in concentrations of 1-, 5- and 10-times the minimal bactericidal concentration (MBC). Finally, treatment-induced differences in bacterial loads and their correlation with biofilm surface parameters were assessed. Results The biofilm surfaces on titanium alloys Ti-6Al-7Nb (Ra = 186 nm) and Ti-6Al-4V (Ra = 270 nm) were less rough than those of biofilms on silicone (Ra = 636 nm). The highest roughness was observed for biofilms on orthopedic bone cement with an Ra of 1,551 nm. Interestingly, the roughness parameters of the titanium alloys themselves were lower than the value for silicone, whereas the surface of the bone cement was the roughest. Treatment with 1- and 5-times the MBC of antibiotics resulted in inter-material differences in colony forming units (CFU) counts, ultimately showing comparable reductions of 2.4-3.0 log CFU/mL at the highest tested concentration. No significant differences in bacterial loads within MRSA biofilms were observed between the various implant materials, upon exposure to increasing concentrations of antibiotics. Discussion The surface parameters of MRSA biofilms were determined by those of the implant materials on which they were formed. The antibiotic susceptibility of MRSA biofilms on the various tested implant materials did not differ, indicating that the efficacy of antibiotics was not affected by the roughness of the biofilm.
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Affiliation(s)
- Sven C. J. van Dun
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
- *Correspondence: Sven C. J. van Dun,
| | - Mariëlle Verheul
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Bart G. C. W. Pijls
- Department of Orthopedics, Leiden University Medical Center, Leiden, Netherlands
| | - Joffrey van Prehn
- Department of Medical Microbiology, Leiden University Medical Center, Leiden, Netherlands
| | - Henk Scheper
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | | | - Peter H. Nibbering
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Mark G. J. de Boer
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
- Mark G. J. de Boer,
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6
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Serrano-Aroca Á, Cano-Vicent A, Sabater i Serra R, El-Tanani M, Aljabali A, Tambuwala MM, Mishra YK. Scaffolds in the microbial resistant era: Fabrication, materials, properties and tissue engineering applications. Mater Today Bio 2022; 16:100412. [PMID: 36097597 PMCID: PMC9463390 DOI: 10.1016/j.mtbio.2022.100412] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 08/23/2022] [Accepted: 08/24/2022] [Indexed: 11/08/2022] Open
Abstract
Due to microbial infections dramatically affect cell survival and increase the risk of implant failure, scaffolds produced with antimicrobial materials are now much more likely to be successful. Multidrug-resistant infections without suitable prevention strategies are increasing at an alarming rate. The ability of cells to organize, develop, differentiate, produce a functioning extracellular matrix (ECM) and create new functional tissue can all be controlled by careful control of the extracellular microenvironment. This review covers the present state of advanced strategies to develop scaffolds with antimicrobial properties for bone, oral tissue, skin, muscle, nerve, trachea, cardiac and other tissue engineering applications. The review focuses on the development of antimicrobial scaffolds against bacteria and fungi using a wide range of materials, including polymers, biopolymers, glass, ceramics and antimicrobials agents such as antibiotics, antiseptics, antimicrobial polymers, peptides, metals, carbon nanomaterials, combinatorial strategies, and includes discussions on the antimicrobial mechanisms involved in these antimicrobial approaches. The toxicological aspects of these advanced scaffolds are also analyzed to ensure future technological transfer to clinics. The main antimicrobial methods of characterizing scaffolds' antimicrobial and antibiofilm properties are described. The production methods of these porous supports, such as electrospinning, phase separation, gas foaming, the porogen method, polymerization in solution, fiber mesh coating, self-assembly, membrane lamination, freeze drying, 3D printing and bioprinting, among others, are also included in this article. These important advances in antimicrobial materials-based scaffolds for regenerative medicine offer many new promising avenues to the material design and tissue-engineering communities.
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Affiliation(s)
- Ángel Serrano-Aroca
- Biomaterials and Bioengineering Lab, Centro de Investigación Traslacional San Alberto Magno, Universidad Católica de Valencia San Vicente Mártir, C/Guillem de Castro 94, 46001, Valencia, Spain
| | - Alba Cano-Vicent
- Biomaterials and Bioengineering Lab, Centro de Investigación Traslacional San Alberto Magno, Universidad Católica de Valencia San Vicente Mártir, C/Guillem de Castro 94, 46001, Valencia, Spain
| | - Roser Sabater i Serra
- Centre for Biomaterials and Tissue Engineering, Universitat Politècnica de València, 46022, València, Spain
| | - Mohamed El-Tanani
- Pharmacological and Diagnostic Research Centre, Faculty of Pharmacy, Al-Ahliyya Amman University, Amman, 19328, Jordan
| | - AlaaAA. Aljabali
- Department of Pharmaceutics and Pharmaceutical Technology, Yarmouk University, Irbid, 21163, Jordan
| | - Murtaza M. Tambuwala
- School of Pharmacy and Pharmaceutical Science, Ulster University, Coleraine, BT52 1SA, UK
| | - Yogendra Kumar Mishra
- Mads Clausen Institute, NanoSYD, University of Southern Denmark, Alsion 2, 6400, Sønderborg, Denmark
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Chronic wound dressings - Pathogenic bacteria anti-biofilm treatment with bacterial cellulose-chitosan polymer or bacterial cellulose-chitosan dots composite hydrogels. Int J Biol Macromol 2021; 191:315-323. [PMID: 34562533 DOI: 10.1016/j.ijbiomac.2021.09.118] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 09/08/2021] [Accepted: 09/17/2021] [Indexed: 01/16/2023]
Abstract
Since the pathogenic bacteria biofilms are involved in 70% of chronic infections and their resistance to antibiotics is increased, the research in this field requires new healing agents. New composite hydrogels were designed as potential chronic wound dressings composed of bacterial cellulose (BC) with chitosan polymer (Chi) - BC-Chi and chitosan nanoparticles (nChiD) - BC-nChiD. nChiD were obtained by gamma irradiation at doses: 20, 40 and 60 kGy. Physical and chemical analyses showed incorporation of Chi and encapsulation of nChiD into BC. The BC-Chi has the highest average surface roughness. BC-nChiD hydrogels show an irradiated dose-dependent increase of average surface roughness. New composite hydrogels are biocompatible with excellent anti-biofilm potential with up to 90% reduction of viable biofilm and up to 65% reduction of biofilm height. The BC-nChiD showed better dressing characteristics: higher porosity, higher wound fluid absorption and faster migration of cells (in vitro healing). All obtained results confirmed both composite hydrogels as promising chronic wound healing agents.
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8
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Insights into the Development of Phototrophic Biofilms in a Bioreactor by a Combination of X-ray Microtomography and Optical Coherence Tomography. Microorganisms 2021; 9:microorganisms9081743. [PMID: 34442822 PMCID: PMC8398007 DOI: 10.3390/microorganisms9081743] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 08/06/2021] [Accepted: 08/12/2021] [Indexed: 11/29/2022] Open
Abstract
As productive biofilms are increasingly gaining interest in research, the quantitative monitoring of biofilm formation on- or offline for the process remains a challenge. Optical coherence tomography (OCT) is a fast and often used method for scanning biofilms, but it has difficulty scanning through more dense optical materials. X-ray microtomography (μCT) can measure biofilms in most geometries but is very time-consuming. By combining both methods for the first time, the weaknesses of both methods could be compensated. The phototrophic cyanobacterium Tolypothrix distorta was cultured in a moving bed photobioreactor inside a biocarrier with a semi-enclosed geometry. An automated workflow was developed to process µCT scans of the biocarriers. This allowed quantification of biomass volume and biofilm-coverage on the biocarrier, both globally and spatially resolved. At the beginning of the cultivation, a growth limitation was detected in the outer region of the carrier, presumably due to shear stress. In the later phase, light limitations could be found inside the biocarrier. µCT data and biofilm thicknesses measured by OCT displayed good correlation. The latter could therefore be used to rapidly measure the biofilm formation in a process. The methods presented here can help gain a deeper understanding of biofilms inside a process and detect any limitations.
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9
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Talluri SNL, Winter RM, Salem DR. Nanoscale characteristics of conditioning film development on photobioreactor materials: influence on the initial adhesion and biofilm formation by a cyanobacterium. BIOFOULING 2021; 37:777-790. [PMID: 34455869 DOI: 10.1080/08927014.2021.1971201] [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: 03/21/2021] [Revised: 08/10/2021] [Accepted: 08/15/2021] [Indexed: 06/13/2023]
Abstract
Adsorption of conditioning films on a solid surface is the first step in the development of biofilms. With the goal of understanding the preliminary adhesion mechanisms of cyanobacteria on photobioreactor (PBR) materials to prevent biofouling, the physical changes occurring on PBR materials were investigated during the initial adhesion and biofilm formation by Anabaena sp. PCC 7120, a cyanobacterium that is genetically modified to produce linalool. Atomic force microscopy (AFM) revealed that the conditioning film deposition was in the form of spike-like structures on all the materials except PVC. The average heights (in the range 9 - 16 nm) of the conditioning films deposited on glass, PMMA, PC and HDPE were 11 to 20 times higher than on PVC at 96 h. The time dependent change in thickness of conditioning films correlated well with Anabaena cell attachment to the PBR materials. The rapid and significant colonization of Anabaena on glass within 48 h was consistent with the increase in thickness of the conditioning film within this time period. Lack of the conditioning film spike structures and no change in thickness of the conditioning films with time on the PVC together with comparatively delayed cell attachment and conditioning-film protein deposition on this material, indicated that the nanoscale spike structures on the other PBR materials may be accelerating the cell attachment process but are not a prerequisite for cell attachment. These results suggest that PVC should be explored further as an antifouling material for photobioreactors. The thickness of the conditioning films on glass measured by a scratch and scan method was in good agreement with the thickness values measured by an adhesive tape method, indicating that both these methods can be used for fast and reliable AFM thickness determination of bacterial conditioning films.
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Affiliation(s)
- Suvarna N L Talluri
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, USA
- Composite and Nanocomposite Advanced Manufacturing - Biomaterials Center (CNAM-Bio), South Dakota School of Mines and Technology, Rapid City, SD, USA
| | - Robb M Winter
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, USA
- Composites and Polymer Engineering Laboratory, South Dakota School of Mines and Technology, Rapid City, SD, USA
| | - David R Salem
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, USA
- Composites and Polymer Engineering Laboratory, South Dakota School of Mines and Technology, Rapid City, SD, USA
- Composite and Nanocomposite Advanced Manufacturing - Biomaterials Center (CNAM-Bio), South Dakota School of Mines and Technology, Rapid City, SD, USA
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10
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Niño-Padilla EI, Velazquez C, Garibay-Escobar A. Mycobacterial biofilms as players in human infections: a review. BIOFOULING 2021; 37:410-432. [PMID: 34024206 DOI: 10.1080/08927014.2021.1925886] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 04/18/2021] [Accepted: 04/28/2021] [Indexed: 06/12/2023]
Abstract
The role of biofilms in pathogenicity and treatment strategies is often neglected in mycobacterial infections. In recent years, the emergence of nontuberculous mycobacterial infections has necessitated the development of novel prophylactic strategies and elucidation of the mechanisms underlying the establishment of chronic infections. More importantly, the question arises whether members of the Mycobacterium tuberculosis complex can form biofilms and contribute to latent tuberculosis and drug resistance because of the long-lasting and recalcitrant nature of its infections. This review discusses some of the molecular mechanisms by which biofilms could play a role in infection or pathological events in humans.
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Affiliation(s)
| | - Carlos Velazquez
- Departamento de Ciencias Químico Biológicas, Universidad de Sonora, Hermosillo, Sonora, México
| | - Adriana Garibay-Escobar
- Departamento de Ciencias Químico Biológicas, Universidad de Sonora, Hermosillo, Sonora, México
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11
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Wu H, Chen Q, Jiao M, Xia X, Lian X, Huang N, Li K, Yin J, Shi B. Evaluation of nanomechanical properties of hyperbranched polyglycerols as prospective cell membrane engineering block. Colloids Surf B Biointerfaces 2020; 190:110968. [DOI: 10.1016/j.colsurfb.2020.110968] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/06/2020] [Accepted: 03/10/2020] [Indexed: 11/29/2022]
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12
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Xiao Y, Sawicka B, Liu Y, Zhou B, Hou P, Li Y. Visualizing the macroscale spatial distributions of biofilms in complex flow channels using industrial computed tomography. BIOFOULING 2020; 36:115-125. [PMID: 32090601 DOI: 10.1080/08927014.2020.1728260] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 02/01/2020] [Accepted: 02/04/2020] [Indexed: 06/10/2023]
Abstract
The presence of biofilms in enclosed pipelines can lead to numerous deleterious issues. To date, it has been difficult to use optical imaging techniques to monitor the macroscale spatial distributions of biofilms. To address this concern, a combination of industrial computed tomography (ICT) and a contrast agent was explored to noninvasively visualize biofilms in three types of drip irrigation emitters. The results showed that ICT successfully observed and quantified the macroscale spatial distributions of biofilms. The complex hydrodynamic characteristics in the emitter channels affected the local distributions of biofilms. Biofilms were mainly attached to the lateral and medial faces and biomass decreased along the flow directions. Based on the distributions of biofilms, some emitter structural design defects were further diagnosed. Applying ICT in combination with the contrast agent could potentially provide a visual and effective way to reveal the formation mechanisms of biofilms and to optimize flow channel structures to avoid biofilm accumulations.
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Affiliation(s)
- Yang Xiao
- College of Water Resources and Civil Engineering, China Agricultural University, Beijing, PR China
| | - Barbara Sawicka
- Department of Plant Production Technology and Commodities Science, University of Life Sciences, Lublin, Poland
| | - Yaoze Liu
- Department of Environmental and Sustainable Engineering, University at Albany, State University of New York, Albany, NY, USA
| | - Bo Zhou
- College of Water Resources and Civil Engineering, China Agricultural University, Beijing, PR China
| | - Peng Hou
- College of Water Resources and Civil Engineering, China Agricultural University, Beijing, PR China
| | - Yunkai Li
- College of Water Resources and Civil Engineering, China Agricultural University, Beijing, PR China
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13
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Kannan P, Su SS, Mannan MS, Castaneda H, Vaddiraju S. A Review of Characterization and Quantification Tools for Microbiologically Influenced Corrosion in the Oil and Gas Industry: Current and Future Trends. Ind Eng Chem Res 2018. [DOI: 10.1021/acs.iecr.8b02211] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Pranav Kannan
- Mary Kay O’Connor Process Safety Center, Texas A&M University System, 3122 TAMU, College Station, Texas 77843-3122, United States
- Artie McFerrin Department of Chemical Engineering, Texas A&M University System, 3122 TAMU, College Station, Texas 77843-3122, United States
| | - Shei Sia Su
- National Corrosion and Materials Reliability Laboratory, Texas A&M University, College Station, Texas 77843-3003, United States
- Materials Science and Engineering Department, Texas A&M University, College Station, Texas 77843-3003, United States
| | - M. Sam Mannan
- Mary Kay O’Connor Process Safety Center, Texas A&M University System, 3122 TAMU, College Station, Texas 77843-3122, United States
- Artie McFerrin Department of Chemical Engineering, Texas A&M University System, 3122 TAMU, College Station, Texas 77843-3122, United States
| | - Homero Castaneda
- National Corrosion and Materials Reliability Laboratory, Texas A&M University, College Station, Texas 77843-3003, United States
- Materials Science and Engineering Department, Texas A&M University, College Station, Texas 77843-3003, United States
| | - Sreeram Vaddiraju
- Mary Kay O’Connor Process Safety Center, Texas A&M University System, 3122 TAMU, College Station, Texas 77843-3122, United States
- Artie McFerrin Department of Chemical Engineering, Texas A&M University System, 3122 TAMU, College Station, Texas 77843-3122, United States
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14
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Furst AL, Smith MJ, Francis MB. New Techniques for the Generation and Analysis of Tailored Microbial Systems on Surfaces. Biochemistry 2018; 57:3017-3026. [DOI: 10.1021/acs.biochem.8b00324] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Ariel L. Furst
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States
| | - Matthew J. Smith
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States
| | - Matthew B. Francis
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720-1460, United States
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15
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Allen A, Habimana O, Casey E. The effects of extrinsic factors on the structural and mechanical properties of Pseudomonas fluorescens biofilms: A combined study of nutrient concentrations and shear conditions. Colloids Surf B Biointerfaces 2018; 165:127-134. [PMID: 29471219 DOI: 10.1016/j.colsurfb.2018.02.035] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Revised: 01/17/2018] [Accepted: 02/14/2018] [Indexed: 12/16/2022]
Abstract
The growth of biofilms on surfaces is a complicated process influenced by several environmental factors such as nutrient availability and fluid shear. In this study, combinations of growth conditions were selected for the study of Pseudomonas fluorescens biofilms including as cultivation time (24- or 48 h), nutrient levels (1:1 or 1:10 King B medium), and shear conditions (75 RPM shaking, 0.4 mL min -1 or 0.7 mL min -1). The use of Confocal Laser Scanning Microscopy (CLSM) determined biofilm structure, while liquid-phase Atomic Force Microscopy (AFM) techniques resolved the mechanical properties of biofilms. Under semi-static conditions, high nutrient environments led to more abundant biofilms with three times higher EPS content compared to biofilms grown under low nutrient conditions. AFM results revealed that biofilms formed under these conditions were less stiff, as shown by their Young's modulus values of 2.35 ± 0.08 kPa, compared to 4.98 ± 0.02 kPa for that of biofilms formed under low nutrient conditions. Under dynamic conditions, however, biofilms exposed to low nutrient conditions and high shear rates led to more developed biofilms compared to other tested dynamic conditions. These biofilms were also found to be significantly more adhesive compared to their counterparts grown at higher nutrient conditions.
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Affiliation(s)
- Ashley Allen
- School of Engineering, The University of Edinburgh, Edinburgh, UK
| | - Olivier Habimana
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region
| | - Eoin Casey
- School of Chemical and Bioprocess Engineering, University College Dublin (UCD), Belfield, Dublin 4, Ireland.
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16
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Effect of alcohol stimulation on salivary pellicle formation on human tooth enamel surface and its lubricating performance. J Mech Behav Biomed Mater 2017; 75:567-573. [DOI: 10.1016/j.jmbbm.2017.05.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 05/16/2017] [Accepted: 05/20/2017] [Indexed: 11/21/2022]
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17
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Abdelwahab MT, Kalyoncu E, Onur T, Baykara MZ, Seker UOS. Genetically-Tunable Mechanical Properties of Bacterial Functional Amyloid Nanofibers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:4337-4345. [PMID: 28388843 DOI: 10.1021/acs.langmuir.7b00112] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Bacterial biofilms are highly ordered, complex, dynamic material systems including cells, carbohydrates, and proteins. They are known to be resistant against chemical, physical, and biological disturbances. These superior properties make them promising candidates for next generation biomaterials. Here we investigated the morphological and mechanical properties (in terms of Young's modulus) of genetically-engineered bacterial amyloid nanofibers of Escherichia coli (E. coli) by imaging and force spectroscopy conducted via atomic force microscopy (AFM). In particular, we tuned the expression and biochemical properties of the major and minor biofilm proteins of E. coli (CsgA and CsgB, respectively). Using appropriate mutants, amyloid nanofibers constituting biofilm backbones are formed with different combinations of CsgA and CsgB, as well as the optional addition of tagging sequences. AFM imaging and force spectroscopy are used to probe the morphology and measure the Young's moduli of biofilm protein nanofibers as a function of protein composition. The obtained results reveal that genetically-controlled secretion of biofilm protein components may lead to the rational tuning of Young's moduli of biofilms as promising candidates at the bionano interface.
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Affiliation(s)
- M Tarek Abdelwahab
- Department of Mechanical Engineering, Bilkent University , Ankara 06800, Turkey
- Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey
- National Nanotechnology Research Center (UNAM), Bilkent University , Ankara 06800, Turkey
| | - Ebuzer Kalyoncu
- Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey
- National Nanotechnology Research Center (UNAM), Bilkent University , Ankara 06800, Turkey
| | - Tugce Onur
- Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey
- National Nanotechnology Research Center (UNAM), Bilkent University , Ankara 06800, Turkey
| | - Mehmet Z Baykara
- Department of Mechanical Engineering, Bilkent University , Ankara 06800, Turkey
- Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey
- National Nanotechnology Research Center (UNAM), Bilkent University , Ankara 06800, Turkey
| | - Urartu Ozgur Safak Seker
- Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey
- National Nanotechnology Research Center (UNAM), Bilkent University , Ankara 06800, Turkey
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18
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The antimicrobial effects of the alginate oligomer OligoG CF-5/20 are independent of direct bacterial cell membrane disruption. Sci Rep 2017; 7:44731. [PMID: 28361894 PMCID: PMC5374485 DOI: 10.1038/srep44731] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 02/13/2017] [Indexed: 12/19/2022] Open
Abstract
Concerns about acquisition of antibiotic resistance have led to increasing demand for new antimicrobial therapies. OligoG CF-5/20 is an alginate oligosaccharide previously shown to have antimicrobial and antibiotic potentiating activity. We investigated the structural modification of the bacterial cell wall by OligoG CF-5/20 and its effect on membrane permeability. Binding of OligoG CF-5/20 to the bacterial cell surface was demonstrated in Gram-negative bacteria. Permeability assays revealed that OligoG CF-5/20 had virtually no membrane-perturbing effects. Lipopolysaccharide (LPS) surface charge and aggregation were unaltered in the presence of OligoG CF-5/20. Small angle neutron scattering and circular dichroism spectroscopy showed no substantial change to the structure of LPS in the presence of OligoG CF-5/20, however, isothermal titration calorimetry demonstrated a weak calcium-mediated interaction. Metabolomic analysis confirmed no change in cellular metabolic response to a range of osmolytes when treated with OligoG CF-5/20. This data shows that, although weak interactions occur between LPS and OligoG CF-5/20 in the presence of calcium, the antimicrobial effects of OligoG CF-5/20 are not related to the induction of structural alterations in the LPS or cell permeability. These results suggest a novel mechanism of action that may avoid the common route in acquisition of resistance via LPS structural modification.
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19
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Zhou Y, Yao J, Ding Y, Yu J, Hua X, Evans JE, Yu X, Lao DB, Heldebrant DJ, Nune SK, Cao B, Bowden ME, Yu XY, Wang XL, Zhu Z. Improving the Molecular Ion Signal Intensity for In Situ Liquid SIMS Analysis. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:2006-2013. [PMID: 27600576 DOI: 10.1007/s13361-016-1478-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Revised: 08/08/2016] [Accepted: 08/10/2016] [Indexed: 06/06/2023]
Abstract
In situ liquid secondary ion mass spectrometry (SIMS) enabled by system for analysis at the liquid vacuum interface (SALVI) has proven to be a promising new tool to provide molecular information at solid-liquid and liquid-vacuum interfaces. However, the initial data showed that useful signals in positive ion spectra are too weak to be meaningful in most cases. In addition, it is difficult to obtain strong negative molecular ion signals when m/z>200. These two drawbacks have been the biggest obstacle towards practical use of this new analytical approach. In this study, we report that strong and reliable positive and negative molecular signals are achievable after optimizing the SIMS experimental conditions. Four model systems, including a 1,8-diazabicycloundec-7-ene (DBU)-base switchable ionic liquid, a live Shewanella oneidensis biofilm, a hydrated mammalian epithelia cell, and an electrolyte popularly used in Li ion batteries were studied. A signal enhancement of about two orders of magnitude was obtained in comparison with non-optimized conditions. Therefore, molecular ion signal intensity has become very acceptable for use of in situ liquid SIMS to study solid-liquid and liquid-vacuum interfaces. Graphical Abstract ᅟ.
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Affiliation(s)
- Yufan Zhou
- School of Physics, State Key Laboratory of Crystal Materials and Key Laboratory of Particle Physics and Particle Irradiation (MOE), Shandong University, Jinan, 250100, China
- W. R. Wiley Environmental Molecular Sciences Laboratory, Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - Juan Yao
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - Yuanzhao Ding
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
- School of Civil and Environmental Engineering and Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Jiachao Yu
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - Xin Hua
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - James E Evans
- W. R. Wiley Environmental Molecular Sciences Laboratory, Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - Xiaofei Yu
- School of Physics, State Key Laboratory of Crystal Materials and Key Laboratory of Particle Physics and Particle Irradiation (MOE), Shandong University, Jinan, 250100, China
- W. R. Wiley Environmental Molecular Sciences Laboratory, Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - David B Lao
- Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - David J Heldebrant
- Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - Satish K Nune
- Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - Bin Cao
- School of Civil and Environmental Engineering and Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Mark E Bowden
- W. R. Wiley Environmental Molecular Sciences Laboratory, Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99354, USA
| | - Xiao-Ying Yu
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99354, USA.
| | - Xue-Lin Wang
- School of Physics, State Key Laboratory of Crystal Materials and Key Laboratory of Particle Physics and Particle Irradiation (MOE), Shandong University, Jinan, 250100, China.
| | - Zihua Zhu
- W. R. Wiley Environmental Molecular Sciences Laboratory, Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99354, USA.
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20
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Azeredo J, Azevedo NF, Briandet R, Cerca N, Coenye T, Costa AR, Desvaux M, Di Bonaventura G, Hébraud M, Jaglic Z, Kačániová M, Knøchel S, Lourenço A, Mergulhão F, Meyer RL, Nychas G, Simões M, Tresse O, Sternberg C. Critical review on biofilm methods. Crit Rev Microbiol 2016; 43:313-351. [PMID: 27868469 DOI: 10.1080/1040841x.2016.1208146] [Citation(s) in RCA: 593] [Impact Index Per Article: 65.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Biofilms are widespread in nature and constitute an important strategy implemented by microorganisms to survive in sometimes harsh environmental conditions. They can be beneficial or have a negative impact particularly when formed in industrial settings or on medical devices. As such, research into the formation and elimination of biofilms is important for many disciplines. Several new methodologies have been recently developed for, or adapted to, biofilm studies that have contributed to deeper knowledge on biofilm physiology, structure and composition. In this review, traditional and cutting-edge methods to study biofilm biomass, viability, structure, composition and physiology are addressed. Moreover, as there is a lack of consensus among the diversity of techniques used to grow and study biofilms. This review intends to remedy this, by giving a critical perspective, highlighting the advantages and limitations of several methods. Accordingly, this review aims at helping scientists in finding the most appropriate and up-to-date methods to study their biofilms.
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Affiliation(s)
- Joana Azeredo
- a CEB ? Centre of Biological Engineering, LIBRO, Laboratórios de Biofilmes Rosário Oliveira, University of Minho Campus de Gualtar , Braga , Portugal
| | - Nuno F Azevedo
- b LEPABE, Department of Chemical Engineering, Faculty of Engineering , University of Porto , Porto , Portugal
| | - Romain Briandet
- c Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay , Jouy-en-Josas , France
| | - Nuno Cerca
- a CEB ? Centre of Biological Engineering, LIBRO, Laboratórios de Biofilmes Rosário Oliveira, University of Minho Campus de Gualtar , Braga , Portugal
| | - Tom Coenye
- d Laboratory of Pharmaceutical Microbiology , Ghent University , Ghent , Belgium
| | - Ana Rita Costa
- a CEB ? Centre of Biological Engineering, LIBRO, Laboratórios de Biofilmes Rosário Oliveira, University of Minho Campus de Gualtar , Braga , Portugal
| | - Mickaël Desvaux
- e INRA Centre Auvergne-Rhône-Alpes , UR454 Microbiologie , Saint-Genès Champanelle , France
| | - Giovanni Di Bonaventura
- f Department of Medical, Oral, and Biotechnological Sciences, and Center of Excellence on Aging and Translational Medicine (CeSI-MeT) , "G. d'Annunzio" University of Chieti-Pescara , Chieti , Italy
| | - Michel Hébraud
- e INRA Centre Auvergne-Rhône-Alpes , UR454 Microbiologie , Saint-Genès Champanelle , France
| | - Zoran Jaglic
- g Department of Food and Feed Safety, Laboratory of Food Bacteriology , Veterinary Research Institute , Brno , Czech Republic
| | - Miroslava Kačániová
- h Department of Microbiology, Faculty of Biotechnology and Food Sciences , Slovak University of Agriculture in Nitra , Nitra , Slovakia
| | - Susanne Knøchel
- i Department of Food Science (FOOD) , University of Copenhagen , Frederiksberg C , Denmark
| | - Anália Lourenço
- j Department of Computer Science , University of Vigo , Ourense , Spain
| | - Filipe Mergulhão
- b LEPABE, Department of Chemical Engineering, Faculty of Engineering , University of Porto , Porto , Portugal
| | - Rikke Louise Meyer
- k Aarhus University, Interdisciplinary Nanoscience Center (iNANO) , Aarhus , Denmark
| | - George Nychas
- l Agricultural University of Athens, Lab of Microbiology and Biotechnology of Foods , Athens , Greece
| | - Manuel Simões
- b LEPABE, Department of Chemical Engineering, Faculty of Engineering , University of Porto , Porto , Portugal
| | - Odile Tresse
- m LUNAM Université, Oniris, SECALIM UMR1024 INRA , Université de Nantes , Nantes , France
| | - Claus Sternberg
- n Department of Biotechnology and Biomedicine , Technical University of Denmark , Lyngby, Denmark
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21
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Atomic force microscopy for the investigation of molecular and cellular behavior. Micron 2016; 89:60-76. [DOI: 10.1016/j.micron.2016.07.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 07/27/2016] [Indexed: 12/19/2022]
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22
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Feng J, Lamour G, Xue R, Mirvakliki MN, Hatzikiriakos SG, Xu J, Li H, Wang S, Lu X. Chemical, physical and morphological properties of bacterial biofilms affect survival of encased Campylobacter jejuni F38011 under aerobic stress. Int J Food Microbiol 2016; 238:172-182. [PMID: 27648759 DOI: 10.1016/j.ijfoodmicro.2016.09.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 06/22/2016] [Accepted: 09/11/2016] [Indexed: 11/18/2022]
Abstract
Campylobacter jejuni is a microaerophilic pathogen and leading cause of human gastroenteritis. The presence of C. jejuni encased in biofilms found in meat and poultry processing facilities may be the major strategy for its survival and dissemination in aerobic environment. In this study, Staphylococcus aureus, Salmonella enterica, or Pseudomonas aeruginosa was mixed with C. jejuni F38011 as a culture to form dual-species biofilms. After 4days' exposure to aerobic stress, no viable C. jejuni cells could be detected from mono-species C. jejuni biofilm. In contrast, at least 4.7logCFU/cm2 of viable C. jejuni cells existed in some dual-species biofilms. To elucidate the mechanism of protection mode, chemical, physical and morphological features of biofilms were characterized. Dual-species biofilms contained a higher level of extracellular polymeric substances with a more diversified chemical composition, especially for polysaccharides and proteins, than mono-species C. jejuni biofilm. Structure of dual-species biofilms was more compact and their surface was >8 times smoother than mono-species C. jejuni biofilm, as indicated by atomic force microscopy. Under desiccation stress, water content of dual-species biofilms decreased slowly and remained at higher levels for a longer time than mono-species C. jejuni biofilm. The surface of all biofilms was hydrophilic, but total surface energy of dual-species biofilms (ranging from 52.5 to 56.2mJ/m2) was lower than that of mono-species C. jejuni biofilm, leading to more resistance to wetting by polar liquids. This knowledge can aid in developing intervention strategies to decrease the survival and dispersal of C. jejuni into foods or environment.
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Affiliation(s)
- Jinsong Feng
- Food, Nutrition, and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Guillaume Lamour
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Rui Xue
- Key Laboratory of Food Nutrition and Safety, Ministry of Education of China, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Mehr Negar Mirvakliki
- Department of Chemical and Biological Engineering, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Savvas G Hatzikiriakos
- Department of Chemical and Biological Engineering, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Jie Xu
- Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, IL 60607, United States
| | - Hongbin Li
- Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Shuo Wang
- Key Laboratory of Food Nutrition and Safety, Ministry of Education of China, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Xiaonan Lu
- Food, Nutrition, and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
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23
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Abdoli L, Suo X, Li H. Distinctive colonization of Bacillus sp. bacteria and the influence of the bacterial biofilm on electrochemical behaviors of aluminum coatings. Colloids Surf B Biointerfaces 2016; 145:688-694. [DOI: 10.1016/j.colsurfb.2016.05.075] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 05/15/2016] [Accepted: 05/26/2016] [Indexed: 10/21/2022]
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24
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Sugimoto S, Okuda KI, Miyakawa R, Sato M, Arita-Morioka KI, Chiba A, Yamanaka K, Ogura T, Mizunoe Y, Sato C. Imaging of bacterial multicellular behaviour in biofilms in liquid by atmospheric scanning electron microscopy. Sci Rep 2016; 6:25889. [PMID: 27180609 PMCID: PMC4867632 DOI: 10.1038/srep25889] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 04/25/2016] [Indexed: 02/04/2023] Open
Abstract
Biofilms are complex communities of microbes that attach to biotic or abiotic surfaces causing chronic infectious diseases. Within a biofilm, microbes are embedded in a self-produced soft extracellular matrix (ECM), which protects them from the host immune system and antibiotics. The nanoscale visualisation of delicate biofilms in liquid is challenging. Here, we develop atmospheric scanning electron microscopy (ASEM) to visualise Gram-positive and -negative bacterial biofilms immersed in aqueous solution. Biofilms cultured on electron-transparent film were directly imaged from below using the inverted SEM, allowing the formation of the region near the substrate to be studied at high resolution. We visualised intercellular nanostructures and the exocytosis of membrane vesicles, and linked the latter to the trafficking of cargos, including cytoplasmic proteins and the toxins hemolysin and coagulase. A thick dendritic nanotube network was observed between microbes, suggesting multicellular communication in biofilms. A universal immuno-labelling system was developed for biofilms and tested on various examples, including S. aureus biofilms. In the ECM, fine DNA and protein networks were visualised and the precise distribution of protein complexes was determined (e.g., straight curli, flagella, and excreted cytoplasmic molecular chaperones). Our observations provide structural insights into bacteria-substratum interactions, biofilm development and the internal microbe community.
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Affiliation(s)
- Shinya Sugimoto
- Department of Bacteriology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-ku, Tokyo 105-8461, Japan.,Jikei Center for Biofilm Science and Technology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Ken-Ichi Okuda
- Department of Bacteriology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-ku, Tokyo 105-8461, Japan.,Jikei Center for Biofilm Science and Technology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Reina Miyakawa
- Department of Bacteriology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Mari Sato
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Higashi 1-1-1, Tsukuba, Ibaraki 305-8566, Japan
| | - Ken-Ichi Arita-Morioka
- Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Chuo-Ku, Kumamoto, 860-0811, Japan
| | - Akio Chiba
- Department of Bacteriology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Kunitoshi Yamanaka
- Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Chuo-Ku, Kumamoto, 860-0811, Japan
| | - Teru Ogura
- Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Chuo-Ku, Kumamoto, 860-0811, Japan
| | - Yoshimitsu Mizunoe
- Department of Bacteriology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-ku, Tokyo 105-8461, Japan.,Jikei Center for Biofilm Science and Technology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Chikara Sato
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Higashi 1-1-1, Tsukuba, Ibaraki 305-8566, Japan
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25
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Trehalose-Induced Variation in Mechanical Properties of Vesicles in Aqueous Solution. J Membr Biol 2015; 248:1121-5. [PMID: 26233566 DOI: 10.1007/s00232-015-9827-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 07/24/2015] [Indexed: 10/23/2022]
Abstract
The effect of the trehalose incorporation on the nanomechanical properties of dipalmitoylphosphatidylcholine vesicles was studied using atomic force microscope (AFM) on mica surface. The vesicles were prepared only with the variation in the trehalose concentration and adsorbed on the mica surface. After the morphology of the adsorbed vesicles was characterized, the behavior of an AFM tip into the vesicle was monitored using the plot of the tip displacement versus the tip deflection. It was observed that the breakthrough of the tip into the vesicles occurred two times. Each breakthrough represented each penetration of the tip into each layer. Force data prior to the first breakthrough fitted well with the Hertzian model to estimate Young's modulus and bending modulus of the vesicles. It was found that the Young's modulus and bending modulus decreased proportionally to the increase in the trehalose concentration up to 0.5 of trehalose to lipid. However, above 0.5, the moduli were a little varied with the increase. In the identical measurements at glucose, just a slight change in the moduli was observed with the increase in the glucose composition from 0 % glucose up to even 2:1 ratio of glucose:lipid. These results in the mechanical properties seem attributable to the osmotic and volumetric effects on the headgroup packing disruption.
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26
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Blauert F, Horn H, Wagner M. Time-resolved biofilm deformation measurements using optical coherence tomography. Biotechnol Bioeng 2015; 112:1893-905. [DOI: 10.1002/bit.25590] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 03/02/2015] [Accepted: 03/09/2015] [Indexed: 11/08/2022]
Affiliation(s)
- Florian Blauert
- Chair of Water Chemistry and Water Technology; Karlsruhe Institute of Technology; Engler-Bunte-Ring 1 D-76131 Karlsruhe Germany
| | - Harald Horn
- Chair of Water Chemistry and Water Technology; Karlsruhe Institute of Technology; Engler-Bunte-Ring 1 D-76131 Karlsruhe Germany
| | - Michael Wagner
- Chair of Water Chemistry and Water Technology; Karlsruhe Institute of Technology; Engler-Bunte-Ring 1 D-76131 Karlsruhe Germany
- Institute of Functional Interfaces; Karlsruhe Institute of Technology; Eggenstein-Leopoldshafen Germany
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27
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Gomes IB, Simões M, Simões LC. An overview on the reactors to study drinking water biofilms. WATER RESEARCH 2014; 62:63-87. [PMID: 24937357 DOI: 10.1016/j.watres.2014.05.039] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 05/21/2014] [Accepted: 05/22/2014] [Indexed: 06/03/2023]
Abstract
The development of biofilms in drinking water distribution systems (DWDS) can cause pipe degradation, changes in the water organoleptic properties but the main problem is related to the public health. Biofilms are the main responsible for the microbial presence in drinking water (DW) and can be reservoirs for pathogens. Therefore, the understanding of the mechanisms underlying biofilm formation and behavior is of utmost importance in order to create effective control strategies. As the study of biofilms in real DWDS is difficult, several devices have been developed. These devices allow biofilm formation under controlled conditions of physical (flow velocity, shear stress, temperature, type of pipe material, etc), chemical (type and amount of nutrients, type of disinfectant and residuals, organic and inorganic particles, ions, etc) and biological (composition of microbial community - type of microorganism and characteristics) parameters, ensuring that the operational conditions are similar as possible to the DWDS conditions in order to achieve results that can be applied to the real scenarios. The devices used in DW biofilm studies can be divided essentially in two groups, those usually applied in situ and the bench top laboratorial reactors. The selection of a device should be obviously in accordance with the aim of the study and its advantages and limitations should be evaluated to obtain reproducible results that can be transposed into the reality of the DWDS. The aim of this review is to provide an overview on the main reactors used in DW biofilm studies, describing their characteristics and applications, taking into account their main advantages and limitations.
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Affiliation(s)
- I B Gomes
- LEPABE, Department of Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal
| | - M Simões
- LEPABE, Department of Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal
| | - L C Simões
- LEPABE, Department of Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal; CEB - Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.
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28
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Chatterjee S, Biswas N, Datta A, Dey R, Maiti P. Atomic force microscopy in biofilm study. Microscopy (Oxf) 2014; 63:269-78. [PMID: 24793174 DOI: 10.1093/jmicro/dfu013] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Biofilms have been classically visualized by Scanning Electron Microscopy (SEM). The complex operating procedure of SEM restricts its use in routine practice. There is a need of newer visualizing techniques for examining surfaces of biofilms, in particular under ambient conditions. We have presented the unique advantages of atomic force microscopy (AFM) in studying surfaces of biofilms through analyses of the height images obtained on biofilms of two gram positive and one gram negative bacteria, namely Staphylococcus aureus, Nocardia brasiliensis and Pseudomonas aeruginosa, respectively. Biofilm quality of the three different bacteria, ageing effects on Nocardia spp. biofilm surface and effects of the antibiotic ciprofloxacin at different doses on Staphylococcus and Pseudomonas biofilm surfaces have been investigated under ambient conditions and distinctive features have been observed.
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Affiliation(s)
- Susmita Chatterjee
- Department of Microbiology, Institute of Post Graduate Medical Education and Research, 244 AJC Bose Road, Kolkata 700 020, India
| | - Nupur Biswas
- Surface Physics and Material Science Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064, India Present address: Department of Physics, Indian Institute of Science, CV Raman Road, Bangalore 560012, India
| | - Alokmay Datta
- Surface Physics and Material Science Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064, India
| | - Rupali Dey
- Department of Microbiology, Institute of Post Graduate Medical Education and Research, 244 AJC Bose Road, Kolkata 700 020, India
| | - Prasantakumar Maiti
- Department of Microbiology, Institute of Post Graduate Medical Education and Research, 244 AJC Bose Road, Kolkata 700 020, India
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Rimboud M, Pocaznoi D, Erable B, Bergel A. Electroanalysis of microbial anodes for bioelectrochemical systems: basics, progress and perspectives. Phys Chem Chem Phys 2014; 16:16349-66. [DOI: 10.1039/c4cp01698j] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Over about the last ten years, microbial anodes have been the subject of a huge number of fundamental studies dealing with an increasing variety of possible application domains.
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Affiliation(s)
- M. Rimboud
- Laboratoire de Génie Chimique
- CNRS - Université de Toulouse
- 31432 Toulouse, France
| | - D. Pocaznoi
- Laboratoire de Génie Chimique
- CNRS - Université de Toulouse
- 31432 Toulouse, France
| | - B. Erable
- Laboratoire de Génie Chimique
- CNRS - Université de Toulouse
- 31432 Toulouse, France
| | - A. Bergel
- Laboratoire de Génie Chimique
- CNRS - Université de Toulouse
- 31432 Toulouse, France
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30
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Pillet F, Chopinet L, Formosa C, Dague E. Atomic Force Microscopy and pharmacology: from microbiology to cancerology. Biochim Biophys Acta Gen Subj 2013; 1840:1028-50. [PMID: 24291690 DOI: 10.1016/j.bbagen.2013.11.019] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 11/18/2013] [Accepted: 11/20/2013] [Indexed: 02/06/2023]
Abstract
BACKGROUND Atomic Force Microscopy (AFM) has been extensively used to study biological samples. Researchers take advantage of its ability to image living samples to increase our fundamental knowledge (biophysical properties/biochemical behavior) on living cell surface properties, at the nano-scale. SCOPE OF REVIEW AFM, in the imaging modes, can probe cells morphological modifications induced by drugs. In the force spectroscopy mode, it is possible to follow the nanomechanical properties of a cell and to probe the mechanical modifications induced by drugs. AFM can be used to map single molecule distribution at the cell surface. We will focus on a collection of results aiming at evaluating the nano-scale effects of drugs, by AFM. Studies on yeast, bacteria and mammal cells will illustrate our discussion. Especially, we will show how AFM can help in getting a better understanding of drug mechanism of action. MAJOR CONCLUSIONS This review demonstrates that AFM is a versatile tool, useful in pharmacology. In microbiology, it has been used to study the drugs fighting Candida albicans or Pseudomonas aeruginosa. The major conclusions are a better understanding of the microbes' cell wall and of the drugs mechanism of action. In cancerology, AFM has been used to explore the effects of cytotoxic drugs or as an innovative diagnostic technology. AFM has provided original results on cultured cells, cells extracted from patient and directly on patient biopsies. GENERAL SIGNIFICANCE This review enhances the interest of AFM technologies for pharmacology. The applications reviewed range from microbiology to cancerology.
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Affiliation(s)
- Flavien Pillet
- CNRS, LAAS, 7 avenue du colonel Roche, F-31077 Toulouse Cedex 4, France; Université de Toulouse, UPS, INSA, INP, ISAE, UT1, UTM, LAAS, ITAV, F-31077 Toulouse Cedex 4, France
| | - Louise Chopinet
- CNRS, IPBS-UMR 5089, BP64182, 205 route de Narbonne, F-31077 Toulouse Cedex 4, France; Université de Toulouse, UPS, INSA, INP, ISAE, UT1, UTM, LAAS, ITAV, F-31077 Toulouse Cedex 4, France
| | - Cécile Formosa
- CNRS, LAAS, 7 avenue du colonel Roche, F-31077 Toulouse Cedex 4, France; Université de Toulouse, UPS, INSA, INP, ISAE, UT1, UTM, LAAS, ITAV, F-31077 Toulouse Cedex 4, France; CNRS, UMR 7565, SRSMC, Vandoeuvre-lès-Nancy, France; Université de Lorraine, UMR 7565, Faculté de Pharmacie, Nancy, France
| | - Etienne Dague
- CNRS, LAAS, 7 avenue du colonel Roche, F-31077 Toulouse Cedex 4, France; Université de Toulouse, UPS, INSA, INP, ISAE, UT1, UTM, LAAS, ITAV, F-31077 Toulouse Cedex 4, France; CNRS; ITAV-USR 3505; F31106 Toulouse, France.
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31
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Gittens JE, Smith TJ, Suleiman R, Akid R. Current and emerging environmentally-friendly systems for fouling control in the marine environment. Biotechnol Adv 2013; 31:1738-53. [PMID: 24051087 DOI: 10.1016/j.biotechadv.2013.09.002] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 09/05/2013] [Accepted: 09/10/2013] [Indexed: 01/25/2023]
Abstract
Following the ban in 2003 on the use of tributyl-tin compounds in antifouling coatings, the search for an environmentally-friendly alternative has accelerated. Biocidal TBT alternatives, such as diuron and Irgarol 1051®, have proved to be environmentally damaging to marine organisms. The issue regarding the use of biocides is that concerning the half-life of the compounds which allow a perpetuation of the toxic effects into the marine food chain, and initiate changes in the early stages of the organisms' life-cycle. In addition, the break-down of biocides can result in metabolites with greater toxicity and longevity than the parent compound. Functionalized coatings have been designed to repel the settlement and permanent attachment of fouling organisms via modification of either or both surface topography and surface chemistry, or by interfering with the natural mechanisms via which fouling organisms settle upon and adhere to surfaces. A large number of technologies are being developed towards producing new coatings that will be able to resist biofouling over a period of years and thus truly replace biocides as antifouling systems. In addition urgent research is directed towards the exploitation of mechanisms used by living organisms designed to repel the settlement of fouling organisms. These biomimetic strategies include the production of antifouling enzymes and novel surface topography that are incompatible with permanent attachment, for example, by mimicking the microstructure of shark skin. Other research seeks to exploit chemical signals and antimicrobial agents produced by diverse living organisms in the environment to prevent settlement and growth of fouling organisms on vulnerable surfaces. Novel polymer-based technologies may prevent fouling by means of unfavourable surface chemical and physical properties or by concentrating antifouling compounds around surfaces.
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Affiliation(s)
- Jeanette E Gittens
- Biomedical Research Centre, Sheffield Hallam University, Howard Street, Sheffield, S1 1WB, UK
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32
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Goode KR, Asteriadou K, Robbins PT, Fryer PJ. Fouling and Cleaning Studies in the Food and Beverage Industry Classified by Cleaning Type. Compr Rev Food Sci Food Saf 2013. [DOI: 10.1111/1541-4337.12000] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kylee R. Goode
- School of Chemical Engineering; Univ. of Birmingham; Edgbaston; Birmingham; B15 2TT; U.K
| | - Konstantia Asteriadou
- School of Chemical Engineering; Univ. of Birmingham; Edgbaston; Birmingham; B15 2TT; U.K
| | - Phillip T. Robbins
- School of Chemical Engineering; Univ. of Birmingham; Edgbaston; Birmingham; B15 2TT; U.K
| | - Peter J. Fryer
- School of Chemical Engineering; Univ. of Birmingham; Edgbaston; Birmingham; B15 2TT; U.K
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33
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Malki M, Casado S, López MF, Caillard R, Palomares FJ, Gago JAM, Vaz-Domínguez C, Cuesta A, Amils R, Fernández VM, Velez M, De Lacey AL, Olea D. Physicochemical Characterization ofAcidiphiliumsp. Biofilms. Chemphyschem 2013; 14:1237-44. [DOI: 10.1002/cphc.201201034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Indexed: 11/07/2022]
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34
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Ribeiro M, Monteiro FJ, Ferraz MP. Infection of orthopedic implants with emphasis on bacterial adhesion process and techniques used in studying bacterial-material interactions. BIOMATTER 2012; 2:176-94. [PMID: 23507884 PMCID: PMC3568104 DOI: 10.4161/biom.22905] [Citation(s) in RCA: 470] [Impact Index Per Article: 36.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Staphylococcus comprises up to two-thirds of all pathogens in orthopedic implant infections and they are the principal causative agents of two major types of infection affecting bone: septic arthritis and osteomyelitis, which involve the inflammatory destruction of joint and bone. Bacterial adhesion is the first and most important step in implant infection. It is a complex process influenced by environmental factors, bacterial properties, material surface properties and by the presence of serum or tissue proteins. Properties of the substrate, such as chemical composition of the material, surface charge, hydrophobicity, surface roughness and the presence of specific proteins at the surface, are all thought to be important in the initial cell attachment process. The biofilm mode of growth of infecting bacteria on an implant surface protects the organisms from the host immune system and antibiotic therapy. The research for novel therapeutic strategies is incited by the emergence of antibiotic-resistant bacteria. This work will provide an overview of the mechanisms and factors involved in bacterial adhesion, the techniques that are currently being used studying bacterial-material interactions as well as provide insight into future directions in the field.
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Affiliation(s)
- Marta Ribeiro
- Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal.
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35
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Papi M, Maiorana A, Bugli F, Torelli R, Posteraro B, Maulucci G, De Spirito M, Sanguinetti M. Detection of biofilm-grown Aspergillus fumigatus by means of atomic force spectroscopy: ultrastructural effects of alginate lyase. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2012; 18:1088-1094. [PMID: 23026204 DOI: 10.1017/s1431927612001067] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Aspergillus fumigatus has become a leading cause of fungal morbidity and mortality, especially in immunocompromised patients. This fungus is able to grow as a multicellular community and produce a hydrophobic extracellular matrix (ECM), mainly composed of galactomannan and α-1,3 glucans, to protect itself from host defenses and antimicrobial drugs. This matrix envelops the fungus hyphae, binding them into a contiguous sheath on the colony surface, forming a biofilm and increasing the fungal resistance to adverse environmental factors. Adherence to host cells and resistance to physical removal play a key role in fungal colonization and invasion of the host and in a wide range of infections. Here we show that, by using atomic force spectroscopy, it is possible to exploit the peculiar hydrophobicity of the biofilm components (i.e., cell walls, ECM) to detect the biofilm spread, its growth, and lysis on rough surfaces. By means of this approach, we demonstrate that alginate lyase, an enzyme known to reduce negatively charged alginate levels in microbial biofilms, reduces the biofilm adhesion forces suggesting a loss of ECM from the biofilm, which could be used to enhance pharmacological treatments.
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Affiliation(s)
- M Papi
- Istituto di Fisica, Università Cattolica del S. Cuore, L. go F. Vito 1, 00168 Roma, Italy
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36
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Lorite GS, de Souza AA, Neubauer D, Mizaikoff B, Kranz C, Cotta MA. On the role of extracellular polymeric substances during early stages of Xylella fastidiosa biofilm formation. Colloids Surf B Biointerfaces 2012; 102:519-25. [PMID: 23164974 DOI: 10.1016/j.colsurfb.2012.08.027] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 08/09/2012] [Accepted: 08/16/2012] [Indexed: 01/15/2023]
Abstract
The structural integrity and protection of bacterial biofilms are intrinsically associated with a matrix of extracellular polymeric substances (EPS) produced by the bacteria cells. However, the role of these substances during biofilm adhesion to a surface remains largely unclear. In this study, the influence of EPS on Xylella fastidiosa biofilm formation was investigated. This bacterium is associated with economically important plant diseases; it presents a slow growth rate and thus allows us to pinpoint more precisely the early stages of cell-surface adhesion. Scanning electron microscopy and atomic force microscopy show evidence of EPS production in such early stages and around individual bacteria cells attached to the substrate surface even a few hours after inoculation. In addition, EPS formation was investigated via attenuated total reflectance (ATR) Fourier transform infrared spectroscopy (FTIR). To this end, X. fastidiosa cells were inoculated within an ATR liquid cell assembly. IR-ATR spectra clearly reveal EPS formation already during the early stages of X. fastidiosa biofilm formation, thereby providing supporting evidence for the hypothesis of the relevance of the EPS contribution to the adhesion process.
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Affiliation(s)
- Gabriela S Lorite
- Departamento de Física Aplicada, Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, Rua Sergio Buarque de Holanda, no 777 Cidade Universitária Zeferino Vaz, 13083-859 Campinas, SP, Brazil.
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37
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Atomic Force Microscopy of the fungi–mineral interface: applications in mineral dissolution, weathering and biogeochemistry. Curr Opin Biotechnol 2012; 23:562-9. [DOI: 10.1016/j.copbio.2012.05.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 05/15/2012] [Accepted: 05/16/2012] [Indexed: 11/18/2022]
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38
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Böl M, Ehret AE, Bolea Albero A, Hellriegel J, Krull R. Recent advances in mechanical characterisation of biofilm and their significance for material modelling. Crit Rev Biotechnol 2012; 33:145-71. [DOI: 10.3109/07388551.2012.679250] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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39
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Hyotyla JT, Lim RYH. Atomic Force Microscopy (AFM). Supramol Chem 2012. [DOI: 10.1002/9780470661345.smc043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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40
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Karimi M, Mahmoodi M, Niazi A, Al-Wahaibi Y, Ayatollahi S. Investigating wettability alteration during MEOR process, a micro/macro scale analysis. Colloids Surf B Biointerfaces 2012; 95:129-36. [PMID: 22445747 DOI: 10.1016/j.colsurfb.2012.02.035] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 02/20/2012] [Accepted: 02/20/2012] [Indexed: 10/28/2022]
Abstract
Wettability alteration is considered to be one of the important mechanisms that lead to increased oil recovery during microbial enhanced oil recovery (MEOR) processes. Changes in wettability will greatly influence the petrophysical properties of the reservoir rocks and determine the location, flow and distribution of different fluids inside the porous media. Understanding the active mechanisms of surface wettability changes by the bacteria would help to optimize the condition for more oil recovery. As the mechanisms behind wettability alteration are still poorly understood, the objective of this study is to investigate the wettability alteration at pore scale and find the most effective mechanism of wettability changes in different cases. The experiments were performed on different substrates at fresh condition or aged in crude oil to mimic various wetting conditions. Using an Enterobacter cloacae strain, the influence of bacterial metabolites, bacterial adhesion and bacterial solution with two different carbon sources on wettability were determined for different aging periods. Contact angle measurements were used to quantify the wettability alteration of the solid surfaces. Atomic force microscopy (AFM) experiments were also utilized to combine the macroscopic measurements of wettability with the microscopic study of the surface changes. It was found that the surface wettability could vary from neutral- or oil-wet to water-wet state. Bacterial adhesion and biofilm formation seems to be the dominant mechanism of wettability alteration. The aged glass surfaces regained their initial water wetness where the bacteria could remove the polar and asphaltene compounds from them.
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Affiliation(s)
- Mahvash Karimi
- School of Chemical and Petroleum Engineering, Shiraz University, Shiraz, Iran
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41
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Effect of aminoglycoside on mechanical properties of zwitterionic phospholipid vesicles. Colloids Surf B Biointerfaces 2011; 88:517-20. [DOI: 10.1016/j.colsurfb.2011.07.046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Accepted: 07/19/2011] [Indexed: 11/20/2022]
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42
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Quantitative evaluation of bacteria adherent and in biofilm on single-wall carbon nanotube-coated surfaces. Interdiscip Perspect Infect Dis 2011; 2011:291513. [PMID: 22007207 PMCID: PMC3189608 DOI: 10.1155/2011/291513] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Revised: 07/07/2011] [Accepted: 08/11/2011] [Indexed: 11/30/2022] Open
Abstract
Biofilm is a common bacterial lifestyle, and it plays a crucial role in human health, causing biofilm-mediated infections. Recently, to counteract biofilm development, new nano-structured biomaterials have been proposed. However, data about the antibacterial properties of nano-structured surfaces are fragmentary and controversial, and, in particular, the susceptibility of nano-structured materials to colonization and biofilm formation by bacterial pathogens has not been yet thoroughly considered. Here, the ability of the pathogenic Streptococcus mutans and Pseudomonas aeruginosa to adhere and form biofilm on surfaces coated with single-wall carbon nanotubes (SWCNTs) was analyzed. Our results showed that the surfaces of SWCNTs-coated glass beads (SWCNTs-GBs) were colonized at the same extent of uncoated GBs both by S. mutans and P. aeruginosa. In conclusion, our results demonstrate that single wall SWCNTs-coated surfaces are not suitable to counteract bacterial adhesion and biofilm development.
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43
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Abe Y, Polyakov P, Skali-Lami S, Francius G. Elasticity and physico-chemical properties during drinking water biofilm formation. BIOFOULING 2011; 27:739-50. [PMID: 21762041 DOI: 10.1080/08927014.2011.601300] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Atomic force microscope techniques and multi-staining fluorescence microscopy were employed to study the steps in drinking water biofilm formation. During the formation of a conditioning layer, surface hydrophobic forces increased and the range of characteristic hydrophobic forces diversified with time, becoming progressively complex in macromolecular composition, which in return triggered irreversible cellular adhesion. AFM visualization of 1 to 8 week drinking water biofilms showed a spatially discontinuous and heterogeneous distribution comprising an extensive network of filamentous fungi in which biofilm aggregates were embedded. The elastic modulus of 40-day-old biofilms ranged from 200 to 9000 kPa, and the biofilm deposits with a height >0.5 μm had an elastic modulus <600 kPa, suggesting that the drinking water biofilms were composed of a soft top layer and a basal layer with significantly higher elastic modulus values falling in the range of fungal elasticity.
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Affiliation(s)
- Yumiko Abe
- Laboratoire de Chimie Physique et Microbiologie pour l'Environnement, UMR 7564, Nancy-University, CNRS, 405 rue de Vandoeuvre, 54600, Villers-lès-Nancy, France
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44
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Lorite GS, Rodrigues CM, de Souza AA, Kranz C, Mizaikoff B, Cotta MA. The role of conditioning film formation and surface chemical changes on Xylella fastidiosa adhesion and biofilm evolution. J Colloid Interface Sci 2011; 359:289-95. [PMID: 21486669 DOI: 10.1016/j.jcis.2011.03.066] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2010] [Revised: 03/17/2011] [Accepted: 03/18/2011] [Indexed: 10/18/2022]
Abstract
Biofilms are complex microbial communities with important biological functions including enhanced resistance against external factors like antimicrobial agents. The formation of a biofilm is known to be strongly dependent on substrate properties including hydrophobicity/hydrophilicity, structure, and roughness. The adsorption of (macro)molecules on the substrate, also known as conditioning film, changes the physicochemical properties of the surface and affects the bacterial adhesion. In this study, we investigate the physicochemical changes caused by Periwinkle wilt (PW) culture medium conditioning film formation on different surfaces (glass and silicon) and their effect on X. fastidiosa biofilm formation. Contact angle measurements have shown that the film formation decreases the surface hydrophilicity degree of both glass and silicon after few hours. Atomic force microscopy (AFM) images show the glass surface roughness is drastically reduced with conditioning film formation. First-layer X. fastidiosa biofilm on glass was observed in the AFM liquid cell after a period of time similar to that determined for the hydrophilicity changes. In addition, attenuation total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy supports the AFM observation, since the PW absorption spectra increases with time showing a stronger contribution from the phosphate groups. Although hydrophobic and rough surfaces are commonly considered to increase bacteria cell attachment, our results suggest that these properties are not as important as the surface functional groups resulting from PW conditioning film formation for X. fastidiosa adhesion and biofilm development.
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Affiliation(s)
- Gabriela S Lorite
- Departamento de Física Aplicada, Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, Campinas, SP, Brazil.
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45
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Probing interfacial interactions of bacteria on metal nanoparticles and substrates with different surface properties. Int J Antimicrob Agents 2010; 36:549-56. [DOI: 10.1016/j.ijantimicag.2010.08.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2010] [Revised: 08/26/2010] [Accepted: 08/27/2010] [Indexed: 11/22/2022]
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46
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Park JW. Ca2+-induced effect on mechanical properties of sulfatide-incorporated vesicles. J Membr Biol 2010; 238:63-8. [PMID: 21088830 DOI: 10.1007/s00232-010-9319-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Accepted: 11/03/2010] [Indexed: 11/24/2022]
Abstract
The Ca(2+)-induced effect on the nanomechanical properties of vesicles prepared at a different ratio of dipalmitoylphosphatidylcholine (DPPC)/sulfatide was studied using atomic force microscope (AFM) on a mica surface. Vesicles were prepared by extrusion and adsorbed on the mica surface. The forces, measured between an AFM tip and the vesicle, showed that the breakthrough of the tip into the vesicles occurred two times. Force data prior to the first breakthrough were fitted well with the Hertzian model to estimate Young's modulus and bending modulus of the vesicles. Sulfatide incorporation led to a decrease of around 90% in Young's modulus and bending modulus of the vesicles due to the hydration of the headgroups, while the addition of Ca(2+) induced dehydration to recover the properties. The change of the physical properties seems to be attributed to the headgroup packing order of the vesicles, which is determined by the interference with the hydration shell.
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Affiliation(s)
- Jin-Won Park
- Department of Chemical Engineering, College of Engineering, Seoul National University of Science and Technology, 172 Gongreung 2-dong, Nowon-gu, Seoul, 139-743, South Korea.
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Park JW. First-leaflet phase effect on properties of phospholipid bilayer formed through vesicle adsorption on LB monolayer. J Membr Biol 2010; 237:107-14. [PMID: 21038105 DOI: 10.1007/s00232-010-9311-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2010] [Accepted: 10/20/2010] [Indexed: 11/26/2022]
Abstract
Phospholipid bilayers were formed on mica using the Langmuir-Blodgett technique and liposome fusion, as a model system for biomembranes. Nanometer-scale surface physical properties of the bilayers were quantitatively characterized upon the different phases of the first leaflets. Lower hydration/steric forces on the bilayers were observed at the liquid phase of the first leaflet than at the solid phase. The forces appear to be related to the low mechanical stability of the lipid bilayer, which was affected by the first leaflet phase. The first leaflet phase also influenced the long-range repulsive forces over the second leaflet. Surface forces, measured using a modified probe with an atomic force microscope, showed that lower long-range repulsive forces were also found at the liquid phase of the first leaflet. Force measurements were performed at 300 mM sodium chloride solution so that the effect of the phase on the long-range repulsive forces could be investigated by reducing the effect of the repulsion between the second-leaflet lipid headgroups on the long-range repulsive forces. Forces were analyzed using the Derjaguin-Landau-Verwey-Overbeek theory so that the surface potential and surface charge density of the lipid bilayers were quantitatively acquired for each phase of the first leaflet.
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Affiliation(s)
- Jin-Won Park
- Department of Chemical Engineering, School of Engineering, Seoul National University of Science and Technology, Nowonku, Seoul 173-743, South Korea.
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Sulfatide incorporation effect on mechanical properties of vesicles. Colloids Surf B Biointerfaces 2010; 80:59-62. [DOI: 10.1016/j.colsurfb.2010.05.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Revised: 05/17/2010] [Accepted: 05/21/2010] [Indexed: 11/20/2022]
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Microbial selectivity on mineral surfaces: possible implications for weathering processes. FUNGAL BIOL REV 2009. [DOI: 10.1016/j.fbr.2009.10.002] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Park JW. Probe chemistry effect on surface properties of asymmetric-phase lipid bilayers. Colloids Surf B Biointerfaces 2009; 75:290-3. [PMID: 19762218 DOI: 10.1016/j.colsurfb.2009.08.047] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2009] [Revised: 08/24/2009] [Accepted: 08/28/2009] [Indexed: 10/20/2022]
Abstract
Phospholipid bilayers were formed on mica using Langmuir-Blodgett technique and liposome fusion, as a model system for biomembranes. Nanometer-scale surface physical properties were quantitatively characterized upon the different phases of the monolayers with the different surface chemistry. The less hydration/steric forces were observed at the liquid-phase of the lipid layer than at the solid-phase for the OH-modified probe, while the forces with the CH(3)-modified probe were independent of the mechanical stability of the layer. The forces appear to be related to the surface chemistry of the probe to the layer as well as the mechanical stability of the lipid layer, which depends on the phase and the asymmetry of the lipid bilayer. After the breakthrough of the lipid bilayer, the CH(3)-modified probe adhered more strongly to the lipid bilayers than do the OH-modified probe. Using results from the JKR theory, it is found that the adhesion can be accounted for in both cases by surface energy consideration, not mechanical effects.
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Affiliation(s)
- Jin-Won Park
- College of BionanoTechnology, Gachon Bionano Research Institute, Kyungwon University, Bokjeongdong, Sujeongku, Sengnamsi, Kyungkido 461-701, South Korea.
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