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Lange A, Matuszewski A, Kutwin M, Ostrowska A, Jaworski S. Farnesol and Selected Nanoparticles (Silver, Gold, Copper, and Zinc Oxide) as Effective Agents Against Biofilms Formed by Pathogenic Microorganisms. Nanotechnol Sci Appl 2024; 17:107-125. [PMID: 38645468 PMCID: PMC11032122 DOI: 10.2147/nsa.s457124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 03/22/2024] [Indexed: 04/23/2024] Open
Abstract
Purpose Biofilms, which are created by most microorganisms, are known for their widely developed drug resistance, even more than planktonic forms of microorganisms. The aim of the study was to assess the effectiveness of agents composed of farnesol and nanoparticles (silver, gold, copper, and zinc oxide) in the degradation of biofilms produced by pathogenic microorganisms. Methods Escherichia coli, Enterococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans were used to create the biofilm structure. Colloidal suspensions of silver, gold, copper, and zinc oxide (Ag, Au, Cu, ZnO) with the addition of farnesol (F) were used as the treatment factor. The size distribution of those composites was analyzed, their zeta potential was measured, and their structure was visualized by transmission electron microscopy. The viability of the microorganism strains was assessed by an XTT assay, the ability to form biofilms was analyzed by confocal microscopy, and the changes in biofilm structure were evaluated by scanning electron microscopy. The general toxicity toward the HFFF2 cell line was determined by a neutral red assay and a human inflammation antibody array. Results The link between the two components (farnesol and nanoparticles) caused mutual stability of both components. Planktonic forms of the microorganisms were the most sensitive when exposed to AgF and CuF; however, the biofilm structure of all microorganism strains was the most disrupted (both inhibition of formation and changes within the structure) after AgF treatment. Composites were not toxic toward the HFFF2 cell line, although the expression of several cytokines was higher than in the not-treated group. Conclusion The in vitro studies demonstrated antibiofilm properties of composites based on farnesol and nanoparticles. The greatest changes in biofilm structure were triggered by AgF, causing an alteration in the biofilm formation process as well as in the biofilm structure.
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Affiliation(s)
- Agata Lange
- Department of Nanobiotechnology, Institute of Biology, Warsaw University of Life Sciences, Warsaw, Poland
| | - Arkadiusz Matuszewski
- Department of Animal Environment Biology, Institute of Animal Sciences, Warsaw University of Life Sciences, Warsaw, Poland
| | - Marta Kutwin
- Department of Nanobiotechnology, Institute of Biology, Warsaw University of Life Sciences, Warsaw, Poland
| | - Agnieszka Ostrowska
- Department of Nanobiotechnology, Institute of Biology, Warsaw University of Life Sciences, Warsaw, Poland
| | - Sławomir Jaworski
- Department of Nanobiotechnology, Institute of Biology, Warsaw University of Life Sciences, Warsaw, Poland
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2
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Barros AC, Narciso DAC, Melo LF, Pereira A. Influence of Dead Cells Killed by Industrial Biocides (BAC and DBNPA) on Biofilm Formation. Antibiotics (Basel) 2024; 13:140. [PMID: 38391526 PMCID: PMC10885908 DOI: 10.3390/antibiotics13020140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 01/27/2024] [Accepted: 01/29/2024] [Indexed: 02/24/2024] Open
Abstract
Industrial biocides aim to keep water systems microbiologically controlled and to minimize biofouling. However, the resulting dead cells are usually not removed from the water streams and can influence the growth of the remaining live cells in planktonic and sessile states. This study aims to understand the effect of dead Pseudomonas fluorescens cells killed by industrial biocides-benzalkonium chloride (BAC) and 2,2-dibromo-3-nitrilopropionamide (DBNPA)-on biofilm formation. Additionally, the effect of different dead/live cell ratios (50.00% and 99.99%) was studied. The inoculum was recirculated in a Parallel Plate Flow Cell (PPFC). The overall results indicate that dead cells greatly affect biofilm properties. Inoculum with DBNPA-dead cells led to more active (higher ATP content and metabolic activity) and thicker biofilm layers in comparison to BAC-dead cells, which seems to be linked to the mechanism of action by which the cells were killed. Furthermore, higher dead cell ratios (99.99%) in the inoculum led to more active (higher culturability, metabolic activity and ATP content) and cohesive/compact and uniformly distributed biofilms in comparison with the 50.00% dead cell ratio. The design of future disinfection strategies must consider the contribution of dead cells to the biofilm build-up, as they might negatively affect water system operations.
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Affiliation(s)
- Ana C Barros
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- ALiCE-Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Diogo A C Narciso
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- ALiCE-Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- CERENA-Centro Recursos Naturais e Ambiente, Department of Chemical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Avenida Rovisco Pais 1, 1049-001 Lisbon, Portugal
| | - Luis F Melo
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- ALiCE-Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Ana Pereira
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- ALiCE-Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
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3
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Gierl L, Horn H, Wagner M. Impact of Fe 2+ and Shear Stress on the Development and Mesoscopic Structure of Biofilms-A Bacillus subtilis Case Study. Microorganisms 2022; 10:2234. [PMID: 36422304 PMCID: PMC9699539 DOI: 10.3390/microorganisms10112234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 11/04/2022] [Accepted: 11/07/2022] [Indexed: 07/25/2023] Open
Abstract
Bivalent cations are known to affect the structural and mechanical properties of biofilms. In order to reveal the impact of Fe2+ ions within the cultivation medium on biofilm development, structure and stability, Bacillus subtilis biofilms were cultivated in mini-fluidic flow cells. Two different Fe2+ inflow concentrations (0.25 and 2.5 mg/L, respectively) and wall shear stress levels (0.05 and 0.27 Pa, respectively) were tested. Mesoscopic biofilm structure was determined daily in situ and non-invasively by means of optical coherence tomography. A set of ten structural parameters was used to quantify biofilm structure, its development and change. The study focused on characterizing biofilm structure and development at the mesoscale (mm-range). Therefore, biofilm replicates (n = 10) were cultivated and analyzed. Three hypotheses were defined in order to estimate the effect of Fe2+ inflow concentration and/or wall shear stress on biofilm development and structure, respectively. It was not the intention to investigate and describe the underlying mechanisms of iron incorporation as this would require a different set of tools applied at microscopic levels as well as the use of, i.e., omic approaches. Fe2+ addition influenced biofilm development (e.g., biofilm accumulation) and structure markedly. Experiments revealed the accumulation of FeO(OH) within the biofilm matrix and a positive correlation of Fe2+ inflow concentration and biofilm accumulation. In more detail, independent of the wall shear stress applied during cultivation, biofilms grew approximately four times thicker at 2.5 mg Fe2+/L (44.8 µmol/L; high inflow concentration) compared to the low Fe2+ inflow concentration of 0.25 mg Fe2+/L (4.48 µmol/L). This finding was statistically verified (Scheirer-Ray-Hare test, ANOVA) and hints at a higher stability of Bacillus subtilis biofilms (e.g., elevated cohesive and adhesive strength) when grown at elevated Fe2+ inflow concentrations.
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Affiliation(s)
- Luisa Gierl
- Water Chemistry and Water Technology, Engler-Bunte-Institut, Karlsruhe Institute of Technology, Engler-Bunte-Ring 9a, 76131 Karlsruhe, Germany
| | - Harald Horn
- Water Chemistry and Water Technology, Engler-Bunte-Institut, Karlsruhe Institute of Technology, Engler-Bunte-Ring 9a, 76131 Karlsruhe, Germany
- German Technical and Scientific Association for Gas and Water (DVGW) Research Site at Karlsruhe Institute of Technology, Water Chemistry and Water Technology, Engler-Bunte-Ring 9a, 76131 Karlsruhe, Germany
| | - Michael Wagner
- Water Chemistry and Water Technology, Engler-Bunte-Institut, Karlsruhe Institute of Technology, Engler-Bunte-Ring 9a, 76131 Karlsruhe, Germany
- Institute of Biological Interfaces (IBG-1), Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
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4
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Li Q, Zhou F, Su Z, Li Y, Li J. Corynebacterium matruchotii: A Confirmed Calcifying Bacterium With a Potentially Important Role in the Supragingival Plaque. Front Microbiol 2022; 13:940643. [PMID: 35875585 PMCID: PMC9298747 DOI: 10.3389/fmicb.2022.940643] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 05/30/2022] [Indexed: 02/05/2023] Open
Abstract
Corynebacterium matruchotii is a reported calcifying bacterium that can usually be isolated from dental calculus and induce mineralization in vitro. In recent years, based on in situ hybridization probe and sequencing technology, researchers have discovered the central "pillar" role of C. matruchotii in supragingival plaque, and many studies focused on bacterial interactions in the biofilm structure dominated by C. matruchotii have been conducted. Besides, C. matruchotii seems to be an indicator of "caries-free" oral status according to imaging and sequencing studies. Therefore, in this review, we summarize C. matruchotii 's role in supragingival plaque based on the structure, interactions, and potential connections with oral diseases.
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Affiliation(s)
- Qinyang Li
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Fangjie Zhou
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Zhifei Su
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yuqing Li
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jiyao Li
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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Li W, Siddique MS, Graham N, Yu W. Influence of Temperature on Biofilm Formation Mechanisms Using a Gravity-Driven Membrane (GDM) System: Insights from Microbial Community Structures and Metabolomics. Environ Sci Technol 2022; 56:8908-8919. [PMID: 35623093 DOI: 10.1021/acs.est.2c01243] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
A biofilm has a significant effect on water treatment processes. Currently, there is a lack of knowledge about the effect of temperature on the biofilm structure in water treatment processes. In this study, a gravity-driven membrane ultrafiltration system was operated with river feedwater at two temperatures ("low", 4 °C; "high", 25 °C) to explore the biofilm structure and transformation mechanism. The results showed that the difference in dissolved oxygen concentration might be one of the main factors regulating the structural components of the biofilm. A denser biofilm formation and reduced flux were observed at the lower temperature. The linoleic acid metabolism was significantly inhibited at low temperature, resulting in enhanced pyrimidine metabolism by Na+ accumulation. In addition, the biofilm at low temperature had a higher proportion of the metabolites of lipids and lipid-like molecules (11.25%), organic acids and derivatives (10.83%), nucleosides, nucleotides, and analogues (7.083%), and organoheterocyclic compounds (6.66%). These small molecules secrete more polysaccharides having C═O and O═C-O functional groups, which intensified the resistance of the biofilm. Furthermore, the upregulation pathway of pyrimidine metabolism also increased the risk of urea accumulation at low temperature. Limnohabitans, Deinococcus, Diaphorobacter, Flavobacterium, and Pseudomonas were identified as the principal microorganisms involved in this metabolic transformation.
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Affiliation(s)
- Weihua Li
- State Key Laboratory of Environmental Aquatic Chemistry, Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Muhammad Saboor Siddique
- State Key Laboratory of Environmental Aquatic Chemistry, Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Nigel Graham
- Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Wenzheng Yu
- State Key Laboratory of Environmental Aquatic Chemistry, Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
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Hill BM, Bisht K, Atkins GR, Gomez AA, Rumbaugh KP, Wakeman CA, Brown AMV. Lysis-Hi-C as a method to study polymicrobial communities and eDNA. Mol Ecol Resour 2021; 22:1029-1042. [PMID: 34669257 PMCID: PMC9215119 DOI: 10.1111/1755-0998.13535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 10/06/2021] [Accepted: 10/11/2021] [Indexed: 11/30/2022]
Abstract
Microbes interact in natural communities in a spatially structured manner, particularly in biofilms and polymicrobial infections. While next generation sequencing approaches provide powerful insights into diversity, metabolic capacity, and mutational profiles of these communities, they generally fail to recover in situ spatial proximity between distinct genotypes in the interactome. Hi‐C is a promising method that has assisted in analysing complex microbiomes, by creating chromatin cross‐links in cells, that aid in identifying adjacent DNA, to improve de novo assembly. This study explored a modified Hi‐C approach involving an initial lysis phase prior to DNA cross‐linking, to test whether adjacent cell chromatin can be cross‐linked, anticipating that this could provide a new avenue for study of spatial‐mutational dynamics in structured microbial communities. An artificial polymicrobial mixture of Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli was lysed for 1–18 h, then prepared for Hi‐C. A murine biofilm infection model was treated with sonication, mechanical lysis, or chemical lysis before Hi‐C. Bioinformatic analyses of resulting Hi‐C interspecies chromatin links showed that while microbial species differed from one another, generally lysis significantly increased links between species and increased the distance of Hi‐C links within species, while also increasing novel plasmid‐chromosome links. The success of this modified lysis‐Hi‐C protocol in creating extracellular DNA links is a promising first step toward a new lysis‐Hi‐C based method to recover genotypic microgeography in polymicrobial communities, with potential future applications in diseases with localized resistance, such as cystic fibrosis lung infections and chronic diabetic ulcers.
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Affiliation(s)
- Bravada M Hill
- Department of Biological Sciences, Texas Tech University, Lubbock, Texas, USA
| | - Karishma Bisht
- Department of Biological Sciences, Texas Tech University, Lubbock, Texas, USA
| | - Georgia Rae Atkins
- Department of Biological Sciences, Texas Tech University, Lubbock, Texas, USA
| | - Amy A Gomez
- Department of Biological Sciences, Texas Tech University, Lubbock, Texas, USA
| | - Kendra P Rumbaugh
- Department of Surgery, School of Medicine, Texas Tech Health Sciences Center, Lubbock, Texas, USA
| | - Catherine A Wakeman
- Department of Biological Sciences, Texas Tech University, Lubbock, Texas, USA
| | - Amanda M V Brown
- Department of Biological Sciences, Texas Tech University, Lubbock, Texas, USA
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7
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de Oliveira A, Pinheiro-Hubinger L, Pereira VC, Riboli DFM, Martins KB, Romero LC, da Cunha MDLRDS. Staphylococcal Biofilm on the Surface of Catheters: Electron Microscopy Evaluation of the Inhibition of Biofilm Growth by RNAIII Inhibiting Peptide. Antibiotics (Basel) 2021; 10:antibiotics10070879. [PMID: 34356800 PMCID: PMC8300745 DOI: 10.3390/antibiotics10070879] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 05/07/2021] [Accepted: 05/11/2021] [Indexed: 12/04/2022] Open
Abstract
Staphylococcus aureus and coagulase-negative staphylococci (CoNS) have become the main causative agents of medical device-related infections due to their biofilm-forming capability, which protects them from the host’s immune system and from the action of antimicrobials. This study evaluated the ability of RNA III inhibiting peptide (RIP) to inhibit biofilm formation in 10 strains isolated from clinical materials, including one S. aureus strain, two S. epidermidis, two S. haemolyticus, two S. lugdunensis, and one isolate each of the following species: S. warneri, S. hominis, and S. saprophyticus. The isolates were selected from a total of 200 strains evaluated regarding phenotypic biofilm production and the presence and expression of the ica operon. The isolates were cultured in trypticase soy broth with 2% glucose in 96-well polystyrene plates containing catheter segments in the presence and absence of RIP. The catheter segments were observed by scanning electron microscopy. The results showed inhibition of biofilm formation in the presence of RIP in all CoNS isolates; however, RIP did not interfere with biofilm formation by S. aureus. RIP is a promising tool that might be used in the future for the prevention of biofilm-related infections caused by CoNS.
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Affiliation(s)
- Adilson de Oliveira
- Department of Chemical and Biological Sciences, Biosciences Institute, UNESP—Universidade Estadual Paulista, Botucatu 18618-691, Brazil; (A.d.O.); (V.C.P.); (D.F.M.R.); (K.B.M.); (L.C.R.); (M.d.L.R.d.S.d.C.)
| | - Luiza Pinheiro-Hubinger
- Department of Anatomic Pathology, Lauro de Souza Lima Institute, Bauru 17034-971, Brazil
- Correspondence: ; Tel.: +55-(0)14-38800428
| | - Valéria Cataneli Pereira
- Department of Chemical and Biological Sciences, Biosciences Institute, UNESP—Universidade Estadual Paulista, Botucatu 18618-691, Brazil; (A.d.O.); (V.C.P.); (D.F.M.R.); (K.B.M.); (L.C.R.); (M.d.L.R.d.S.d.C.)
| | - Danilo Flávio Moraes Riboli
- Department of Chemical and Biological Sciences, Biosciences Institute, UNESP—Universidade Estadual Paulista, Botucatu 18618-691, Brazil; (A.d.O.); (V.C.P.); (D.F.M.R.); (K.B.M.); (L.C.R.); (M.d.L.R.d.S.d.C.)
| | - Katheryne Benini Martins
- Department of Chemical and Biological Sciences, Biosciences Institute, UNESP—Universidade Estadual Paulista, Botucatu 18618-691, Brazil; (A.d.O.); (V.C.P.); (D.F.M.R.); (K.B.M.); (L.C.R.); (M.d.L.R.d.S.d.C.)
| | - Letícia Calixto Romero
- Department of Chemical and Biological Sciences, Biosciences Institute, UNESP—Universidade Estadual Paulista, Botucatu 18618-691, Brazil; (A.d.O.); (V.C.P.); (D.F.M.R.); (K.B.M.); (L.C.R.); (M.d.L.R.d.S.d.C.)
| | - Maria de Lourdes Ribeiro de Souza da Cunha
- Department of Chemical and Biological Sciences, Biosciences Institute, UNESP—Universidade Estadual Paulista, Botucatu 18618-691, Brazil; (A.d.O.); (V.C.P.); (D.F.M.R.); (K.B.M.); (L.C.R.); (M.d.L.R.d.S.d.C.)
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8
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Niederdorfer R, Fragner L, Yuan L, Hausherr D, Wei J, Magyar P, Joss A, Lehmann MF, Ju F, Bürgmann H. Distinct growth stages controlled by the interplay of deterministic and stochastic processes in functional anammox biofilms. Water Res 2021; 200:117225. [PMID: 34052477 DOI: 10.1016/j.watres.2021.117225] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 04/30/2021] [Accepted: 05/04/2021] [Indexed: 06/12/2023]
Abstract
Mainstream anaerobic ammonium oxidation (anammox) represents one of the most promising energy-efficient mechanisms of fixed nitrogen elimination from wastewaters. However, little is known about the exact processes and drivers of microbial community assembly within the complex microbial biofilms that support anammox in engineered ecosystems. Here, we followed anammox biofilm development on fresh carriers in an established 8m3 mainstream anammox reactor that is exposed to seasonal temperature changes (~25-12°C) and varying NH4+ concentrations (5-25 mg/L). We use fluorescence in situ hybridization and 16S rRNA gene sequencing to show that three distinct stages of biofilm development emerge naturally from microbial community composition and biofilm structure. Neutral modelling and network analysis are employed to elucidate the relative importance of stochastic versus deterministic processes and synergistic and antagonistic interactions in the biofilms during their development. We find that the different phases are characterized by a dynamic succession and an interplay of both stochastic and deterministic processes. The observed growth stages (Colonization, Succession and Maturation) appear to be the prerequisite for the anticipated growth of anammox bacteria and for reaching a biofilm community structure that supports the desired metabolic and functional capacities observed for biofilm carriers already present in the system (~100gNH4-N m3 d-1). We discuss the relevance of this improved understanding of anammox-community ecology and biofilm development in the context of its practical application in the start-up, configuration, and optimization of anammox biofilm reactors.
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Affiliation(s)
- Robert Niederdorfer
- Eawag, Swiss Federal Institute for Aquatic Science and Technology, Department of Surface Waters-Research and Management, 6047 Kastanienbaum, Switzerland.
| | - Lisa Fragner
- Eawag, Swiss Federal Institute for Aquatic Science and Technology, Department of Surface Waters-Research and Management, 6047 Kastanienbaum, Switzerland
| | - Ling Yuan
- Key Laboratory of Coastal Environment and Resources of Zhejiang Province, School of Engineering, Westlake University, Hangzhou, China
| | - Damian Hausherr
- Eawag, Swiss Federal Institute for Aquatic Science and Technology, Department of Process Engineering, 8600 Duebendorf, Switzerland
| | - Jing Wei
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Air Pollution & Environmental Technology, 8600 Duebendorf, Switzerland
| | - Paul Magyar
- Department of Environmental Sciences, University of Basel, Basel, Switzerland
| | - Adriano Joss
- Eawag, Swiss Federal Institute for Aquatic Science and Technology, Department of Process Engineering, 8600 Duebendorf, Switzerland
| | - Moritz F Lehmann
- Department of Environmental Sciences, University of Basel, Basel, Switzerland
| | - Feng Ju
- Key Laboratory of Coastal Environment and Resources of Zhejiang Province, School of Engineering, Westlake University, Hangzhou, China
| | - Helmut Bürgmann
- Eawag, Swiss Federal Institute for Aquatic Science and Technology, Department of Surface Waters-Research and Management, 6047 Kastanienbaum, Switzerland
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Olszewska MA, Diez-Gonzalez F. Characterization of Binary Biofilms of Listeria monocytogenes and Lactobacillus and Their Response to Chlorine Treatment. Front Microbiol 2021; 12:638933. [PMID: 34335486 PMCID: PMC8317434 DOI: 10.3389/fmicb.2021.638933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 06/14/2021] [Indexed: 11/17/2022] Open
Abstract
In nature, Listeria may interact competitively and cooperatively with other organisms, resulting in unique spatial organization and functions for cells within the community. This study was undertaken to characterize the biofilm architecture of binary biofilms of Listeria monocytogenes and Lactobacillus species and to assess their effect on the survival of Listeria during exposure to hypochlorite. Three L. monocytogenes strains, ATCC 19115 (Lm5), ATCC 19117 (Lm7), and Coleslaw (LmC), were selected and combined individually with three Lactobacillus strains: L. fermentum (Lf), L. bavaricus (Lb), and L. plantarum (Lp). In binary Lm-Lp biofilms, the Lm cell counts were similar to single-species biofilms (8.5 log CFU/well), and the Lp cell numbers declined by 1.0 log CFU/well. In the presence of Lb, the Lm cell counts were reduced by 1.5 log CFU/well (p < 0.05), whereas the Lf cell counts increased at least by 3.5 log CFU/well. Confocal laser scanning microscopy (CLSM) determined that interspecies interactions significantly affected the spatial organization of three binary biofilms. Biofilm surface-to-volume ratio increased from 0.8 μm2/μm3 for Lm5 in the monoculture to 2.1 μm2/μm3 for Lm5-Lp in the dual-species model (p < 0.05), and was characterized by a thicker structure with a largely increased surface area. Biofilm roughness increased from 0.2 for Lm7 to 1.0 for Lm7-Lb biofilms (p < 0.05), which appeared as interspecific segregation. Biofilm thickness increased from 34.2 μm for LmC to 46.3 μm for LmC–Lf (p < 0.05), which produced flat and compact structures that covered the entire surface available. The biomass of the extracellular matrix was higher in the case of some binary biofilms (p < 0.05); however, this effect was dependent upon the species pair. When treated with hypochlorite, Lm5 in binary biofilms had an approximately 1.5 log CFU/well greater survival than individually. The unique spatial organization and greater protein production may explain the protective effect of Lp after hypochlorite exposure.
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Affiliation(s)
- Magdalena A Olszewska
- Center for Food Safety, College of Agricultural and Environmental Sciences, University of Georgia, Griffin, GA, United States.,Department of Industrial and Food Microbiology, Faculty of Food Science, University of Warmia and Mazury in Olsztyn, Olsztyn, Poland
| | - Francisco Diez-Gonzalez
- Center for Food Safety, College of Agricultural and Environmental Sciences, University of Georgia, Griffin, GA, United States
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10
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Liu C, Xu C, Du Y, Liu J, Ning Y. Role of agglutinin-like sequence protein 3 (Als3) in the structure and antifungal resistance of Candida albicans biofilms. FEMS Microbiol Lett 2021; 368:6316779. [PMID: 34232317 DOI: 10.1093/femsle/fnab089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Accepted: 07/05/2021] [Indexed: 11/13/2022] Open
Abstract
Agglutinin-like sequence protein 3 (Als3) is a cell surface glycoprotein of Candida albicans that plays essential roles in the processes of adherence and biofilm formation in vitro. In this study, we focused on the contribution of Als3 to the structure and drug susceptibility of biofilms. The C. albicans wild-type (WT) strain DAY185, the als3Δ/Δ null strain and the als3Δ/Δ + pALS3 complemented strain were used. Colony-forming unit enumeration, crystal violet and cell surface hydrophobicity assays, scanning electron microscopy and confocal laser scanning microscopy coupled with analyses using COMSTAT software were performed to evaluate the biomass and architecture of the biofilms. The detailed architectural analysis showed a significant variation in the biofilm parameters of the als3Δ/Δ biofilms compared with those of the WT biofilms. Fluconazole, miconazole and amphotericin B were selected as the antifungal agents for the antimycotic susceptibility test, and increased susceptibility was found with the ALS3 deletion biofilms. A quantitative real-time polymerase chain reaction analysis showed downregulation of biofilm formation-related genes (ALS1, EFG1, HWP1 and CSH1) and drug resistance-related genes (ERG11, CDR1, CDR2 and MDR1) in the als3Δ/Δ biofilms. We concluded that Als3 contributes to biofilm formation by changing the biofilm architecture and is involved in the antifungal resistance of C. albicans biofilms.
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Affiliation(s)
- Chang Liu
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, 56 Lingyuanxi Road, Guangzhou 510055, China
| | - Cheng Xu
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, 56 Lingyuanxi Road, Guangzhou 510055, China
| | - Yu Du
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, 56 Lingyuanxi Road, Guangzhou 510055, China
| | - Jia Liu
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, 56 Lingyuanxi Road, Guangzhou 510055, China
| | - Yang Ning
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, 56 Lingyuanxi Road, Guangzhou 510055, China
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11
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Lawal OU, Barata M, Fraqueza MJ, Worning P, Bartels MD, Goncalves L, Paixão P, Goncalves E, Toscano C, Empel J, Urbaś M, Domiìnguez MA, Westh H, de Lencastre H, Miragaia M. Staphylococcus saprophyticus From Clinical and Environmental Origins Have Distinct Biofilm Composition. Front Microbiol 2021; 12:663768. [PMID: 34163443 PMCID: PMC8216562 DOI: 10.3389/fmicb.2021.663768] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 04/27/2021] [Indexed: 11/13/2022] Open
Abstract
Biofilm formation has been shown to be critical to the success of uropathogens. Although Staphylococcus saprophyticus is a common cause of urinary tract infections, its biofilm production capacity, composition, genetic basis, and origin are poorly understood. We investigated biofilm formation in a large and diverse collection of S. saprophyticus (n = 422). Biofilm matrix composition was assessed in representative strains (n = 63) belonging to two main S. saprophyticus lineages (G and S) recovered from human infection, colonization, and food-related environment using biofilm detachment approach. To identify factors that could be associated with biofilm formation and structure variation, we used a pangenome-wide association study approach. Almost all the isolates (91%; n = 384/422) produced biofilm. Among the 63 representative strains, we identified eight biofilm matrix phenotypes, but the most common were composed of protein or protein-extracellular DNA (eDNA)-polysaccharides (38%, 24/63 each). Biofilms containing protein-eDNA-polysaccharides were linked to lineage G and environmental isolates, whereas protein-based biofilms were produced by lineage S and infection isolates (p < 0.05). Putative biofilm-associated genes, namely, aas, atl, ebpS, uafA, sasF, sasD, sdrH, splE, sdrE, sdrC, sraP, and ica genes, were found with different frequencies (3-100%), but there was no correlation between their presence and biofilm production or matrix types. Notably, icaC_1 was ubiquitous in the collection, while icaR was lineage G-associated, and only four strains carried a complete ica gene cluster (icaADBCR) except one that was without icaR. We provided evidence, using a comparative genomic approach, that the complete icaADBCR cluster was acquired multiple times by S. saprophyticus and originated from other coagulase-negative staphylococci. Overall, the composition of S. saprophyticus biofilms was distinct in environmental and clinical isolates, suggesting that modulation of biofilm structure could be a key step in the pathogenicity of these bacteria. Moreover, biofilm production in S. saprophyticus is ica-independent, and the complete icaADBCR was acquired from other staphylococci.
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Affiliation(s)
- Opeyemi U. Lawal
- Laboratory of Bacterial Evolution and Molecular Epidemiology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade NOVA de Lisboa, Oeiras, Portugal
- Laboratory of Molecular Genetics, Instituto de Tecnologia Química e Biológica António Xavier, Universidade NOVA de Lisboa, Oeiras, Portugal
| | - Marta Barata
- Laboratory of Bacterial Evolution and Molecular Epidemiology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade NOVA de Lisboa, Oeiras, Portugal
| | - Maria J. Fraqueza
- Centre for Interdisciplinary Research in Animal Health, Faculdade de Medicina Veterinária, Universidade de Lisboa, Lisbon, Portugal
| | - Peder Worning
- Department of Clinical Microbiology, Hvidovre University Hospital, Hvidovre, Denmark
| | - Mette D. Bartels
- Department of Clinical Microbiology, Hvidovre University Hospital, Hvidovre, Denmark
| | | | | | | | | | - Joanna Empel
- Department of Epidemiology and Clinical Microbiology, Narodowy Instytut Leków, Warszawa, Poland
| | - Malgorzata Urbaś
- Department of Epidemiology and Clinical Microbiology, Narodowy Instytut Leków, Warszawa, Poland
| | | | - Henrik Westh
- Department of Clinical Microbiology, Hvidovre University Hospital, Hvidovre, Denmark
- Institute of Clinical Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hermínia de Lencastre
- Laboratory of Molecular Genetics, Instituto de Tecnologia Química e Biológica António Xavier, Universidade NOVA de Lisboa, Oeiras, Portugal
- The Laboratory of Microbiology and Infectious Diseases, The Rockefeller University, New York, NY, United States
| | - Maria Miragaia
- Laboratory of Bacterial Evolution and Molecular Epidemiology, Instituto de Tecnologia Química e Biológica António Xavier, Universidade NOVA de Lisboa, Oeiras, Portugal
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12
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Faria SI, Teixeira-Santos R, Romeu MJ, Morais J, Jong E, Sjollema J, Vasconcelos V, Mergulhão FJ. Unveiling the Antifouling Performance of Different Marine Surfaces and Their Effect on the Development and Structure of Cyanobacterial Biofilms. Microorganisms 2021; 9:1102. [PMID: 34065462 DOI: 10.3390/microorganisms9051102] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/10/2021] [Accepted: 05/17/2021] [Indexed: 01/12/2023] Open
Abstract
Since biofilm formation by microfoulers significantly contributes to the fouling process, it is important to evaluate the performance of marine surfaces to prevent biofilm formation, as well as understand their interactions with microfoulers and how these affect biofilm development and structure. In this study, the long-term performance of five surface materials—glass, perspex, polystyrene, epoxy-coated glass, and a silicone hydrogel coating—in inhibiting biofilm formation by cyanobacteria was evaluated. For this purpose, cyanobacterial biofilms were developed under controlled hydrodynamic conditions typically found in marine environments, and the biofilm cell number, wet weight, chlorophyll a content, and biofilm thickness and structure were assessed after 49 days. In order to obtain more insight into the effect of surface properties on biofilm formation, they were characterized concerning their hydrophobicity and roughness. Results demonstrated that silicone hydrogel surfaces were effective in inhibiting cyanobacterial biofilm formation. In fact, biofilms formed on these surfaces showed a lower number of biofilm cells, chlorophyll a content, biofilm thickness, and percentage and size of biofilm empty spaces compared to remaining surfaces. Additionally, our results demonstrated that the surface properties, together with the features of the fouling microorganisms, have a considerable impact on marine biofouling potential.
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Abstract
Biofilms are structured communities formed by a single or multiple microbial species. Within biofilms, bacteria are embedded into extracellular matrix, allowing them to build macroscopic objects. Biofilm structure can respond to environmental changes such as the presence of antibiotics or predators. By adjusting expression levels of surface and extracellular matrix components, bacteria tune cell-to-cell interactions. One major challenge in the field is the fact that these components are very diverse among different species. Deciphering how physical interactions within biofilms are affected by changes in gene expression is a promising approach to obtaining a more unified picture of how bacteria modulate biofilms. This review focuses on recent advances in characterizing attractive and repulsive forces between bacteria in correlation with biofilm structure, dynamics, and spreading. How bacteria control physical interactions to maximize their fitness is an emerging theme.
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Affiliation(s)
- Berenike Maier
- Institute for Biological Physics and Center for Molecular Medicine Cologne, University of Cologne, 50674 Cologne, Germany;
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14
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Beckwith JK, VanEpps JS, Solomon MJ. Differential Effects of Heated Perfusate on Morphology, Viability, and Dissemination of Staphylococcus epidermidis Biofilms. Appl Environ Microbiol 2020; 86:e01193-20. [PMID: 32801173 DOI: 10.1128/AEM.01193-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 08/03/2020] [Indexed: 01/11/2023] Open
Abstract
Bacterial biofilms are a leading cause of medical device infections. Staphylococcus epidermidis is commonly responsible for these types of infections. With increasing occurrences of antibacterial resistance, there has been a new push to explore treatment options that augment traditional antibiotic therapies. Here, we show how thermal treatment can be applied to both degrade bacterial biofilms on substrates and impede the proliferation of cells that detach from them. Understanding the response of both surface-adhered and dispersed bacterial cells under thermal stress conditions is a foundational step toward the development of an in situ treatment/remediation method for biofilm growth in medical devices; such an application could use oscillatory flow of heated fluid in a catheter as an adjuvant to antibiotic treatment. The work furthermore provides new insight into the viability of disseminated biofilm material. The biofilm phenotype offers bacterial communities protection from environmental factors, as evidenced by its role in the viability, persistence, and virulence of cells under conditions in which flow is present, such as in riverbeds, industrial piping networks, and the human circulatory system. Here, we examined the hypothesis that temperature—an environmental factor that affects the growth of the Gram-positive bacterium Staphylococcus epidermidis—controls, through dual mechanisms, persistence of this bacterial strain in a shear environment characteristic of the human circulatory system. We demonstrated that temperature and antibiotics impact the surface-adhered biofilm and material disseminated downstream in different ways. Specifically, by means of three-dimensional (3D) confocal and scanning electron microscopy, an increase in surface-adhered biofilm heterogeneity was observed with increasing temperature. Additionally, we found a 4-log decrease in cell viability at the biofilm surface as the perfusate temperature was increased from 37°C to 50°C. Finally, the viability of cell-containing fragments that were disseminated from the substrate was assessed by downstream sampling, culture, and optical density measurement. We found that although temperature decreased the viability of the surface-adhered biofilm, the downstream material remained viable. And yet, in the presence of antibiotics, the growth of disseminated material was nearly completely inhibited, even though the addition of antibiotics had no significant impact on the viability of the surface-adhered biofilm. The mechanism involves both biofilm structural damage, as quantified by morphology of debrided material, and reduced cell viability, as quantified by assay of bacterial cells present in the surface-adherent biofilm and in the downstream effluent. The results potentially identify parameter ranges in which elevated temperature could augment current antibiotic treatment regimens. IMPORTANCE Bacterial biofilms are a leading cause of medical device infections. Staphylococcus epidermidis is commonly responsible for these types of infections. With increasing occurrences of antibacterial resistance, there has been a new push to explore treatment options that augment traditional antibiotic therapies. Here, we show how thermal treatment can be applied to both degrade bacterial biofilms on substrates and impede the proliferation of cells that detach from them. Understanding the response of both surface-adhered and dispersed bacterial cells under thermal stress conditions is a foundational step toward the development of an in situ treatment/remediation method for biofilm growth in medical devices; such an application could use oscillatory flow of heated fluid in a catheter as an adjuvant to antibiotic treatment. The work furthermore provides new insight into the viability of disseminated biofilm material.
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15
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Alamiri F, Chao Y, Baumgarten M, Riesbeck K, Hakansson AP. A Role of Epithelial Cells and Virulence Factors in Biofilm Formation by Streptococcus pyogenes In Vitro. Infect Immun 2020; 88:e00133-20. [PMID: 32661124 DOI: 10.1128/IAI.00133-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 07/07/2020] [Indexed: 02/05/2023] Open
Abstract
Biofilm formation by Streptococcus pyogenes (group A streptococcus [GAS]) in model systems mimicking the respiratory tract is poorly documented. Most studies have been conducted on abiotic surfaces, which poorly represent human tissues. We have previously shown that GAS forms mature and antibiotic-resistant biofilms on physiologically relevant epithelial cells. However, the roles of the substratum, extracellular matrix (ECM) components, and GAS virulence factors in biofilm formation and structure are unclear. In this study, biofilm formation was measured on respiratory epithelial cells and keratinocytes by determining biomass and antibiotic resistance, and biofilm morphology was visualized using scanning electron microscopy. All GAS isolates tested formed biofilms that had similar, albeit not identical, biomass and antibiotic resistance for both cell types. Interestingly, functionally mature biofilms formed more rapidly on keratinocytes but were structurally denser and coated with more ECM on respiratory epithelial cells. The ECM was crucial for biofilm integrity, as protein- and DNA-degrading enzymes induced bacterial release from biofilms. Abiotic surfaces supported biofilm formation, but these biofilms were structurally less dense and organized. No major role for M protein, capsule, or streptolysin O was observed in biofilm formation on epithelial cells, although some morphological differences were detected. NAD-glycohydrolase was required for optimal biofilm formation, whereas streptolysin S and cysteine protease SpeB impaired this process. Finally, no correlation was found between cell adherence or autoaggregation and GAS biofilm formation. Combined, these results provide a better understanding of the role of biofilm formation in GAS pathogenesis and can potentially provide novel targets for future treatments against GAS infections.
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16
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Vazquez-Munoz R, Lopez FD, Lopez-Ribot JL. Bismuth Nanoantibiotics Display Anticandidal Activity and Disrupt the Biofilm and Cell Morphology of the Emergent Pathogenic Yeast Candida auris. Antibiotics (Basel) 2020; 9:E461. [PMID: 32751405 PMCID: PMC7460268 DOI: 10.3390/antibiotics9080461] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 07/27/2020] [Accepted: 07/28/2020] [Indexed: 01/08/2023] Open
Abstract
Candida auris is an emergent multidrug-resistant pathogenic yeast, which forms biofilms resistant to antifungals, sanitizing procedures, and harsh environmental conditions. Antimicrobial nanomaterials represent an alternative to reduce the spread of pathogens-including yeasts-regardless of their drug-resistant profile. Here we have assessed the antimicrobial activity of easy-to-synthesize bismuth nanoparticles (BiNPs) against the emergent multidrug-resistant yeast Candida auris, under both planktonic and biofilm growing conditions. Additionally, we have examined the effect of these BiNPs on cell morphology and biofilm structure. Under planktonic conditions, BiNPs MIC values ranged from 1 to 4 µg mL-1 against multiple C. auris strains tested, including representatives of all different clades. Regarding the inhibition of biofilm formation, the calculated BiNPs IC50 values ranged from 5.1 to 113.1 µg mL-1. Scanning electron microscopy (SEM) observations indicated that BiNPs disrupted the C. auris cell morphology and the structure of the biofilms. In conclusion, BiNPs displayed strong antifungal activity against all strains of C. auris under planktonic conditions, but moderate activity against biofilm growth. BiNPs may potentially contribute to reducing the spread of C. auris strains at healthcare facilities, as sanitizers and future potential treatments. More research on the antimicrobial activity of BiNPs is warranted.
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Affiliation(s)
- Roberto Vazquez-Munoz
- Department of Biology, and South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Fernando D. Lopez
- School of Engineering, The University of Texas at Austin, Austin, TX 78712, USA;
| | - Jose L. Lopez-Ribot
- Department of Biology, and South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX 78249, USA
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17
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Liu C, Zhu L, Chen L. Mechanism of biofilm formation on a hydrophobic polytetrafluoroethylene membrane during the purification of surface water using direct contact membrane distillation (DCMD), with especial interest in the feed properties. Biofouling 2020; 36:14-31. [PMID: 31928216 DOI: 10.1080/08927014.2019.1710136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 12/20/2019] [Accepted: 12/22/2019] [Indexed: 06/10/2023]
Abstract
The impact of feed water quality on biofilm formation during membrane distillation (MD) was investigated in this study, particularly emphasizing the interrelationship between organics, salts, and microbes. Two types of typical natural surface waters in Nanjing, China, were chosen as feed solutions for long-term MD operation, including the Qinhuai River and Xuanwu Lake. The biofilms that developed under different feed water qualities exhibited distinct Foulant compositions and structures, causing different flux decline trends for the MD system. Accordingly, two typical patterns of biofilm formation were suggested for the MD operation of the two different kinds of surface waters in this study. Organics from a primal feed solution and dead bacteria were the key to the establishment of a biofilm on the membrane, and this needs to be effectively removed from the MD system through pre-treatment and process control strategies. Finally, a feasible strategy for MD biofouling control was suggested.
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Affiliation(s)
- Chang Liu
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, China
- College of Environment, Hohai University, Nanjing, China
| | - Liang Zhu
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, China
- College of Environment, Hohai University, Nanjing, China
| | - Lin Chen
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, China
- College of Environment, Hohai University, Nanjing, China
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18
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Amin M, Navidifar T, Shooshtari FS, Rashno M, Savari M, Jahangirmehr F, Arshadi M. Association Between Biofilm Formation, Structure, and the Expression Levels of Genes Related to biofilm formation and Biofilm-Specific Resistance of Acinetobacter baumannii Strains Isolated from Burn Infection in Ahvaz, Iran. Infect Drug Resist 2019; 12:3867-3881. [PMID: 31853190 PMCID: PMC6914661 DOI: 10.2147/idr.s228981] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 11/15/2019] [Indexed: 12/18/2022] Open
Abstract
Background The ability of biofilm formation is an effective way for Acinetobacter baumannii survival from stressed conditions. This present study was aimed to evaluate the association between biofilm formation, structure, the expression levels of genes related to biofilm formation and biofilm-specific resistance of A. baumannii strains isolated from burn infections in Ahvaz, Iran. Methods In this study, we assessed the antibiotic susceptibilities, ERIC-PCR typing, capacity of biofilm formation and biofilm structure of 64 A. baumannii isolates collected from burn infections. The distribution and the expression levels of genes involved in the biofilm formation including bap, ompA, abaI, pgaA and csuE were assessed by PCR and real-time PCR, respectively. Results We classified A. baumannii isolates in 14 clonal types of ERIC-PCR. Most A. baumannii isolates were resistant to all antibiotics tested except to tigecycline and colistin and had the biofilm formation capability but with different capacities. There was a significant inverse relationship between resistance to antibiotic agents and biofilm formation. The biofilm matrix of 50 strains consisted of polysaccharides together with DNA or proteins. The genes involved in the biofilm formation were detected in both biofilm-forming and non-biofilm forming; however, the expression levels of these genes were higher in biofilm producers compared with non-producers. Conclusion The biofilm cells exhibited dramatically decreased susceptibility to antibiotic agents; hence, they have great significance for public health. Therefore, the determination of antibiotic susceptibilities in biofilm and planktonic mode, molecular typing, and capacity of biofilm formation in clinical setting is essential.
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Affiliation(s)
- Mansour Amin
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.,Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Tahereh Navidifar
- Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.,Cellular and Molecular Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Farkhondeh Saleh Shooshtari
- Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.,Infertility Research and Treatment Center of Jahad Daneshgahi, Ahvaz, Khuzestan, Iran
| | - Mohammad Rashno
- Cellular and Molecular Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.,Department of Immunology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Mohammad Savari
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.,Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Fatemeh Jahangirmehr
- Pain Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Mania Arshadi
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
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19
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Wang T, Flint S, Palmer J. Magnesium and calcium ions: roles in bacterial cell attachment and biofilm structure maturation. Biofouling 2019; 35:959-974. [PMID: 31687841 DOI: 10.1080/08927014.2019.1674811] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 09/27/2019] [Indexed: 06/10/2023]
Abstract
The ubiquitous divalent cations magnesium and calcium are important nutrients required by bacteria for growth and cell maintenance. Multi-faceted roles are shown both in bacterial initial attachment and biofilm maturation. The effects of calcium and magnesium can be highlighted in physio-chemical interactions, gene regulation and bio-macromolecular structural modification, which lead to either promotion or inhibition of biofilms. This review outlines recent research addressing phenotypic changes and mechanisms undertaken by calcium and magnesium in affecting bacterial biofilm formation.
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Affiliation(s)
- Tianyang Wang
- Institute of Food Science and Technology, School of Food and Advanced Technology, Massey University, New Zealand
| | - Steve Flint
- Institute of Food Science and Technology, School of Food and Advanced Technology, Massey University, New Zealand
| | - Jon Palmer
- Institute of Food Science and Technology, School of Food and Advanced Technology, Massey University, New Zealand
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20
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Lei W, Bruchmann J, Rüping JL, Levkin PA, Schwartz T. Biofilm Bridges Forming Structural Networks on Patterned Lubricant-Infused Surfaces. Adv Sci (Weinh) 2019; 6:1900519. [PMID: 31380192 PMCID: PMC6662098 DOI: 10.1002/advs.201900519] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 03/21/2019] [Indexed: 05/05/2023]
Abstract
Despite many decades of research, biofilm architecture and spreading mechanisms are still not clear because of the heterogenous 3D structure within biofilms. Here, patterned "slippery" lubricant-infused porous surfaces are utilized to study biofilm structure of Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Staphylococcus aureus. It is found that bacteria are able to spread over bacteria-repellent lubricant-infused regions by using a mechanism, termed "biofilm bridges". Here, it is demonstrated that bacteria use bridges to form interconnected networks between distant biofilm colonies. Detailed structure of bridges shows a spatial distribution of bacteria with an accumulation of respiratory active bacteria and biomass in the bridges. The core-shell structure of bridges formed by two-species mixed population is illustrated. It is demonstrated that eDNA and nutrients have a strong effect on biofilm bridges formation. Thus, it is believed that biofilm bridging is important to reveal the structure and communication within biofilms.
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Affiliation(s)
- Wenxi Lei
- Institute of Toxicology and GeneticsKarlsruhe Institute of TechnologyHermann‐von‐Helmholtz Platz 176344Eggenstein‐LeopoldshafenGermany
| | - Julia Bruchmann
- Institute of Functional InterfacesKarlsruhe Institute of TechnologyHermann‐von‐Helmholtz Platz 176344Eggenstein‐LeopoldshafenGermany
| | - Jan Lars Rüping
- Institute of Functional InterfacesKarlsruhe Institute of TechnologyHermann‐von‐Helmholtz Platz 176344Eggenstein‐LeopoldshafenGermany
| | - Pavel A. Levkin
- Institute of Toxicology and GeneticsKarlsruhe Institute of TechnologyHermann‐von‐Helmholtz Platz 176344Eggenstein‐LeopoldshafenGermany
- Institute of Organic ChemistryKarlsruhe Institute of Technology76131KarlsruheGermany
| | - Thomas Schwartz
- Institute of Functional InterfacesKarlsruhe Institute of TechnologyHermann‐von‐Helmholtz Platz 176344Eggenstein‐LeopoldshafenGermany
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21
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Guo J, Qin S, Wei Y, Liu S, Peng H, Li Q, Luo L, Lv M. Silver nanoparticles exert concentration-dependent influences on biofilm development and architecture. Cell Prolif 2019; 52:e12616. [PMID: 31050052 PMCID: PMC6668980 DOI: 10.1111/cpr.12616] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 03/15/2019] [Accepted: 03/20/2019] [Indexed: 12/12/2022] Open
Abstract
Objectives To investigate the impact of silver nanoparticles (AgNPs) on the biofilm growth and architecture. Materials and methods Silver nitrate was reduced by d‐maltose to prepare AgNPs in the presence of ammonia and sodium hydroxide. The physicochemical properties of AgNPs were characterized by transmission electron microscopy, ultraviolet‐visible spectroscopy and inductively coupled plasma mass spectrometry. The development of biofilm with and without AgNPs was explored by crystal violet stain. The structures of mature biofilm were visually studied by confocal laser scanning microscopy and scanning electron microscopy. Bacterial cell, polysaccharide and protein within biofilm were assessed quantitatively by colony‐counting method, phenol‐sulphuric acid method and Bradford assay, respectively. Results The spherical AgNPs (about 30 nm) were successfully synthesized. The effect of AgNPs on Pseudomonas aeruginosa biofilm development was concentration‐dependent. Biofilm was more resistant to AgNPs than planktonic cells. Low doses of AgNPs exposure remarkably delayed the growth cycle of biofilm, whereas high concentration (18 μg/mL) of AgNPs fully prevented biofilm development. The analysis of biofilm architecture at the mature stage demonstrated that AgNPs exposure at all concentration led to significant decrease of cell viability within treated biofilms. However, sublethal doses of AgNPs increased the production of both polysaccharide and protein compared to control, which significantly changed the biofilm structure. Conclusions AgNPs exert concentration‐dependent influences on biofilm development and structure, which provides new insight into the role of concentration played in the interaction between antibacterial nanoparticles and biofilm, especially, an ignored sublethal concentration associated with potential unintended consequences.
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Affiliation(s)
- Jingyang Guo
- College of Sciences, Shanghai University, Shanghai, China.,Division of Physical Biology & Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China
| | - Simin Qin
- Division of Physical Biology & Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yan Wei
- Key Lab of Health Technology Assessment (National Health Commission), School of Public Health, Fudan University, Shanghai, China
| | - Shima Liu
- College of Sciences, Shanghai University, Shanghai, China.,Division of Physical Biology & Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China
| | - Hongzhen Peng
- Division of Physical Biology & Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China.,Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, China
| | - Qingnuan Li
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China
| | - Liqiang Luo
- College of Sciences, Shanghai University, Shanghai, China
| | - Min Lv
- Division of Physical Biology & Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China.,Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, China
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22
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Kim SK, Li XH, Hwang HJ, Lee JH. Antibiofilm effect of biofilm-dispersing agents on clinical isolates of Pseudomonas aeruginosa with various biofilm structures. J Microbiol 2018; 56:902-909. [PMID: 30361978 DOI: 10.1007/s12275-018-8336-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 08/16/2018] [Accepted: 08/21/2018] [Indexed: 12/25/2022]
Abstract
Pseudomonas aeruginosa, an opportunistic human pathogen, causes many biofilm-mediated chronic infections. In this study, biofilm structures of various clinical strains of P. aeruginosa isolated from hospitalized patients were examined and their influence on the biofilm-dispersing effects of chemicals was investigated. The clinical isolates formed structurally distinct biofilms that could be classified into three different groups: 1) mushroom-like, 2) thin flat, and 3) thick flat structures. A dispersion of these differently structured biofilms was induced using two biofilm-dispersing agents, anthranilate and sodium nitroprusside (SNP). Although both SNP and anthranilate could disperse all types of biofilms, the thick flat biofilms were dispersed less efficiently than the biofilms of other structures. This suggests that biofilm-dispersing agents have higher potency on the biofilms of porous structures than on densely packed biofilms.
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Affiliation(s)
- Soo-Kyoung Kim
- Department of Pharmacy, College of Pharmacy, Pusan National University, Busan, 46241, Republic of Korea
| | - Xi-Hui Li
- Department of Pharmacy, College of Pharmacy, Pusan National University, Busan, 46241, Republic of Korea
| | - Hyeon-Ji Hwang
- Department of Pharmacy, College of Pharmacy, Pusan National University, Busan, 46241, Republic of Korea
| | - Joon-Hee Lee
- Department of Pharmacy, College of Pharmacy, Pusan National University, Busan, 46241, Republic of Korea.
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23
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Stewart EJ, Payne DE, Ma TM, VanEpps JS, Boles BR, Younger JG, Solomon MJ. Effect of Antimicrobial and Physical Treatments on Growth of Multispecies Staphylococcal Biofilms. Appl Environ Microbiol 2017; 83:e03483-16. [PMID: 28411222 DOI: 10.1128/AEM.03483-16] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Accepted: 04/08/2017] [Indexed: 12/18/2022] Open
Abstract
The prevalence and structure of Staphylococcus aureus and Staphylococcus epidermidis within multispecies biofilms were found to depend sensitively on physical environment and antibiotic dosage. Although these species commonly infect similar sites, such as orthopedic implants, little is known about their behavior in multispecies communities, particularly in response to treatment. This research establishes that S. aureus is much more prevalent than S. epidermidis when simultaneously seeded and grown under unstressed conditions (pH 7, 37°C) in both laboratory and clinical strains. In multispecies communities, S. epidermidis is capable of growing a more confluent biofilm when the addition of S. aureus is delayed 4 to 6 h during 18 h of growth. Different vancomycin dosages generate various behaviors: S. epidermidis is more prevalent at a dose of 1.0 μg/ml vancomycin, but reduced growth of both species occurs at 1.9 μg/ml vancomycin. This variability is consistent with the different MICs of S. aureus and S. epidermidis Growth at higher temperature (45°C) results in an environment where S. aureus forms porous biofilms. This porosity allows S. epidermidis to colonize more of the surface, resulting in detectable S. epidermidis biomass. Variations in pH result in increased prevalence of S. epidermidis at low pH (pH 5 and 6), while S. aureus remains dominant at high pH (pH 8 and 9). This work establishes the structural variability of multispecies staphylococcal biofilms as they undergo physical and antimicrobial treatments. It provides a basis for understanding the structure of these communities at infection sites and how treatments disrupt their multispecies behaviors.IMPORTANCEStaphylococcus aureus and Staphylococcus epidermidis are two species of bacteria that are commonly responsible for biofilm infections on medical devices. Biofilms are structured communities of bacteria surrounded by polysaccharides, proteins, and DNA; bacteria are more resistant to antimicrobials as part of a biofilm than as individual cells. This work investigates the structure and prevalence of these two organisms when grown together in multispecies biofilms and shows shifts in the behavior of the polymicrobial community when grown in various concentrations of vancomycin (an antibiotic commonly used to treat staphylococcal infections), in a high-temperature environment (a condition previously shown to lead to cell disruption and death), and at low and high pH (a change that has been previously shown to soften the mechanical properties of staphylococcal biofilms). These shifts in community structure demonstrate the effect such treatments may have on multispecies staphylococcal infections.
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24
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Cherifi T, Jacques M, Quessy S, Fravalo P. Impact of Nutrient Restriction on the Structure of Listeria monocytogenes Biofilm Grown in a Microfluidic System. Front Microbiol 2017; 8:864. [PMID: 28567031 DOI: 10.3389/fmicb.2017.00864] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 04/28/2017] [Indexed: 12/19/2022] Open
Abstract
Biofilm formation by the pathogen Listeria monocytogenes is a major concern in food industries. The aim of this work was to elucidate the effect of nutrient limitation on both biofilm architecture and on the viability of the bacteria in microfluidic growth conditions. Biofilm formation by two L. monocytogenes strains was performed in a rich medium (BHI) and in a 10-fold diluted BHI (BHI/10) at 30°C for 24 h by using both static conditions and the microfluidic system Bioflux. In dynamic conditions, biofilms grown in rich and poor medium showed significant differences as well in structure and in the resulting biovolume. In BHI/10, biofilm was organized in a knitted network where cells formed long chains, whereas in the rich medium, the observed structure was homogeneous cellular multilayers. Biofilm biovolume production in BHI/10 was significantly higher than in BHI in these dynamic conditions. Interestingly, biovolume of dead cells in biofilms formed under limited nutrient conditions (BHI/10) was significantly higher than in biofilms formed in the BHI medium. In the other hand, in static conditions, biofilm is organized in a multilayer cells and dispersed cells in a rich medium BHI and poor medium BHI/10 respectively. There was significantly more biomass in the rich medium compared to BHI/10 but no difference was noted in the dead/damaged subpopulation showing how L. monocytogenes biofilm could be affected by the growth conditions. This work demonstrated that nutrient concentration affects biofilm structure and the proportion of dead cells in biofilms under microfluidic condition. Our study also showed that limited nutrients play an important role in the structural stability of L. monocytogenes biofilm by enhancing cell death and liberating extracellular DNA.
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Affiliation(s)
- Tamazight Cherifi
- Chaire de recherche en salubrité des viandes, Faculté de médecine vétérinaire, Université de MontréalSaint-Hyacinthe, QC, Canada.,Groupe de Recherche sur les Maladies Infectieuses du Porc, Faculté de médecine vétérinaire, Université de MontréalSaint-Hyacinthe, QC, Canada.,Centre de Recherche en Infectiologie Porcine et Avicole, Faculté de médecine vétérinaire, Université de MontréalSaint-Hyacinthe, QC, Canada
| | - Mario Jacques
- Chaire de recherche en salubrité des viandes, Faculté de médecine vétérinaire, Université de MontréalSaint-Hyacinthe, QC, Canada.,Centre de Recherche en Infectiologie Porcine et Avicole, Faculté de médecine vétérinaire, Université de MontréalSaint-Hyacinthe, QC, Canada.,Réseau canadien de recherche sur la mammite bovine et la qualité du lait, Faculté de médecine vétérinaire, Université de MontréalSaint-Hyacinthe, QC, Canada
| | - Sylvain Quessy
- Chaire de recherche en salubrité des viandes, Faculté de médecine vétérinaire, Université de MontréalSaint-Hyacinthe, QC, Canada.,Groupe de Recherche sur les Maladies Infectieuses du Porc, Faculté de médecine vétérinaire, Université de MontréalSaint-Hyacinthe, QC, Canada.,Centre de Recherche en Infectiologie Porcine et Avicole, Faculté de médecine vétérinaire, Université de MontréalSaint-Hyacinthe, QC, Canada
| | - Philippe Fravalo
- Chaire de recherche en salubrité des viandes, Faculté de médecine vétérinaire, Université de MontréalSaint-Hyacinthe, QC, Canada.,Groupe de Recherche sur les Maladies Infectieuses du Porc, Faculté de médecine vétérinaire, Université de MontréalSaint-Hyacinthe, QC, Canada.,Centre de Recherche en Infectiologie Porcine et Avicole, Faculté de médecine vétérinaire, Université de MontréalSaint-Hyacinthe, QC, Canada
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25
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Abstract
We extend the one-dimensional polymer solution theory of bacterial biofilm growth described by Winstanley et al. (2011 Proc. R. Soc. A467, 1449-1467 (doi:10.1098/rspa.2010.0327)) to deal with the problem of the growth of a patch of biofilm in more than one lateral dimension. The extension is non-trivial, as it requires consideration of the rheology of the polymer phase. We use a novel asymptotic technique to reduce the model to a free-boundary problem governed by the equations of Stokes flow with non-standard boundary conditions. We then consider the stability of laterally uniform biofilm growth, and show that the model predicts spatial instability; this is confirmed by a direct numerical solution of the governing equations. The instability results in cusp formation at the biofilm surface and provides an explanation for the common observation of patterned biofilm architectures.
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Affiliation(s)
- A C Fowler
- MACSI, University of Limerick, Limerick, Republic of Ireland; OCIAM, University of Oxford, Oxford, UK
| | | | - H F Winstanley
- MACSI , University of Limerick , Limerick, Republic of Ireland
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26
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Römling U, Galperin MY. Bacterial cellulose biosynthesis: diversity of operons, subunits, products, and functions. Trends Microbiol 2015; 23:545-57. [PMID: 26077867 DOI: 10.1016/j.tim.2015.05.005] [Citation(s) in RCA: 296] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 05/05/2015] [Accepted: 05/18/2015] [Indexed: 12/30/2022]
Abstract
Recent studies of bacterial cellulose biosynthesis, including structural characterization of a functional cellulose synthase complex, provided the first mechanistic insight into this fascinating process. In most studied bacteria, just two subunits, BcsA and BcsB, are necessary and sufficient for the formation of the polysaccharide chain in vitro. Other subunits - which differ among various taxa - affect the enzymatic activity and product yield in vivo by modulating (i) the expression of the biosynthesis apparatus, (ii) the export of the nascent β-D-glucan polymer to the cell surface, and (iii) the organization of cellulose fibers into a higher-order structure. These auxiliary subunits play key roles in determining the quantity and structure of resulting biofilms, which is particularly important for the interactions of bacteria with higher organisms - leading to rhizosphere colonization and modulating the virulence of cellulose-producing bacterial pathogens inside and outside of host cells. We review the organization of four principal types of cellulose synthase operon found in various bacterial genomes, identify additional bcs genes that encode components of the cellulose biosynthesis and secretion machinery, and propose a unified nomenclature for these genes and subunits. We also discuss the role of cellulose as a key component of biofilms and in the choice between acute infection and persistence in the host.
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Affiliation(s)
- Ute Römling
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Stockholm, Sweden.
| | - Michael Y Galperin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
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27
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Hu XB, Xu K, Wang Z, Ding LL, Ren HQ. Characteristics of biofilm attaching to carriers in moving bed biofilm reactor used to treat vitamin C wastewater. Scanning 2013; 35:283-291. [PMID: 23168685 DOI: 10.1002/sca.21064] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2012] [Accepted: 10/12/2012] [Indexed: 06/01/2023]
Abstract
In order to investigate characteristics of biofilm attaching firmly to carriers in the moving bed biofilm reactor (MBBR) used for vitamin C wastewater treatment, experiments were undertaken with instrumental analysis methods. Scanning electron microscopy (SEM) micrographs of MBBR biofilms revealed that there were rod-shaped microbes and cocci in the biofilm, and microbes were embedded within medium substances and the biofilm matrix adhered firmly to carriers, leading to the formation of a smooth compacted surface at the base of the biofilm. Transmission electron microscopy (TEM) analysis revealed that extracellular polymeric substances (EPS) layer surrounded cell, sequestered inorganics to form a mixed structure, which ensured firm attachment of the biofilm to the carrier. X-ray diffraction (XRD) experiments and thermogravimetry analysis revealed that (i) the biofilm contained many inorganic substances, about 70.5%, and the inorganic substances contained multiple classes of inorganic with a high boiling point; (ii) inorganic elements such as calcium and phosphorous were selectively absorbed and accumulated in the biofilm as insoluble compounds with amorphous phases, rendering the biofilm highly resistant to detachment. Fourier-transform infrared (FTIR) spectroscopy showed carbohydrates were the main EPS.
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Affiliation(s)
- Xiao-bing Hu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, People's Republic of China
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28
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Abstract
Microorganisms attach to surfaces and develop biofilms. Biofilm-associated cells can be differentiated from their suspended counterparts by generation of an extracellular polymeric substance (EPS) matrix, reduced growth rates, and the up- and down- regulation of specific genes. Attachment is a complex process regulated by diverse characteristics of the growth medium, substratum, and cell surface. An established biofilm structure comprises microbial cells and EPS, has a defined architecture, and provides an optimal environment for the exchange of genetic material between cells. Cells may also communicate via quorum sensing, which may in turn affect biofilm processes such as detachment. Biofilms have great importance for public health because of their role in certain infectious diseases and importance in a variety of device-related infections. A greater understanding of biofilm processes should lead to novel, effective control strategies for biofilm control and a resulting improvement in patient management.
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Affiliation(s)
- Rodney M Donlan
- Biofilm Laboratory, Division of Healthcare Quality Promotion, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
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