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Richter-Dahlfors A, Kärkkäinen E, Choong FX. Fluorescent optotracers for bacterial and biofilm detection and diagnostics. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2023; 24:2246867. [PMID: 37680974 PMCID: PMC10481766 DOI: 10.1080/14686996.2023.2246867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 07/03/2023] [Accepted: 08/07/2023] [Indexed: 09/09/2023]
Abstract
Effective treatment of bacterial infections requires methods that accurately and quickly identify which antibiotic should be prescribed. This review describes recent research on the development of optotracing methodologies for bacterial and biofilm detection and diagnostics. Optotracers are small, chemically well-defined, anionic fluorescent tracer molecules that detect peptide- and carbohydrate-based biopolymers. This class of organic molecules (luminescent conjugated oligothiophenes) show unique electronic, electrochemical and optical properties originating from the conjugated structure of the compounds. The photophysical properties are further improved as donor-acceptor-donor (D-A-D)-type motifs are incorporated in the conjugated backbone. Optotracers bind their biopolymeric target molecules via electrostatic interactions. Binding alters the optical properties of these tracer molecules, shown as altered absorption and emission spectra, as well as ON-like switch of fluorescence. As the optotracer provides a defined spectral signature for each binding partner, a fingerprint is generated that can be used for identification of the target biopolymer. Alongside their use for in situ experimentation, optotracers have demonstrated excellent use in studies of a number of clinically relevant microbial pathogens. These methods will find widespread use across a variety of communities engaged in reducing the effect of antibiotic resistance. This includes basic researchers studying molecular resistance mechanisms, academia and pharma developing new antimicrobials targeting biofilm infections and tests to diagnose biofilm infections, as well as those developing antibiotic susceptibility tests for biofilm infections (biofilm-AST). By iterating between the microbial world and that of plants, development of the optotracing technology has become a prime example of successful cross-feeding across the boundaries of disciplines. As optotracers offers a capacity to redefine the way we work with polysaccharides in the microbial world as well as with plant biomass, the technology is providing novel outputs desperately needed for global impact of the threat of antimicrobial resistance as well as our strive for a circular bioeconomy.
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Affiliation(s)
- Agneta Richter-Dahlfors
- AIMES – Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
- Department of Fiber and Polymer Technology, School of Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Elina Kärkkäinen
- AIMES – Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Ferdinand X. Choong
- AIMES – Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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Inthalaeng N, Dugmore TIJ, Matharu AS. Production of Hydrogels from Microwave-Assisted Hydrothermal Fractionation of Blackcurrant Pomace. Gels 2023; 9:674. [PMID: 37754357 PMCID: PMC10530458 DOI: 10.3390/gels9090674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 08/12/2023] [Accepted: 08/17/2023] [Indexed: 09/28/2023] Open
Abstract
The exploitation of unavoidable food supply chain wastes resulting from primary and secondary processing for chemicals, materials, and bioenergy is an important concept in the drive towards circular-based, resource-efficient biorefineries rather than petroleum refineries. The potential production of hydrogels (materials) from unavoidable food supply chain wastes, which are naturally rich in biopolymers such as cellulose, hemicellulose, pectin, and lignin, represents an interesting opportunity. However, these intertwined and interconnected biopolymers require separation and deconstruction prior to any useful application. Thus, this study aims to explore the formation of hydrogels from defibrillated celluloses (MW-DFCs) produced via acid-free stepwise microwave hydrothermal processing of blackcurrant pomace residues. Initially, pectin was removed from blackcurrant pomace residues (MW, 100-160 °C), and the resultant depectinated residues were reprocessed at 160 °C. The pectin yield increased from 2.36 wt.% (MW, 100 °C) to 3.07 wt.% (MW, 140 °C) and then decreased to 2.05 wt.% (MW, 160 °C). The isolated pectins were characterized by attenuated total reflectance infrared spectroscopy (ATR-IR), thermogravimetric analysis (TGA), and 13C NMR (D2O). The cellulosic-rich residues were reprocessed (MW, 160 °C) and further characterized by ATR-IR, TGA, and Klason lignin analysis. All the MW-DFCs contained significant lignin content, which prevented hydrogel formation. However, subsequent bleaching (H2O2/OH-) afforded off-white samples with improved gelling ability at the concentration of 5% w/v. Confocal laser microscopy (CLSM) revealed the removal of lignin and a more pronounced cellulosic-rich material. In conclusion, the microwave-assisted defibrillation of blackcurrant pomace, an exploitable unavoidable food supply chain waste, affords cellulosic-rich materials with the propensity to form hydrogels which may serve useful applications when put back into food products, pharmaceuticals, cosmetics, and home and personal care products.
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Affiliation(s)
| | | | - Avtar S. Matharu
- Green Chemistry Centre of Excellence, Department of Chemistry, University of York, York YO10 5DD, UK; (N.I.); (T.I.J.D.)
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3
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Liu D, He G, Liu J, Zhang X, Zhang J, Duan Z. Synthesis and characterization of new donor-acceptor oligothiophene derivative with pyrido[1,2,5]thiadiazole as electron accepting unit. J Mol Struct 2023. [DOI: 10.1016/j.molstruc.2023.135418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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4
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Choong FX, Huzell S, Rosenberg M, Eckert JA, Nagaraj M, Zhang T, Melican K, Otzen DE, Richter-Dahlfors A. A semi high-throughput method for real-time monitoring of curli producing Salmonella biofilms on air-solid interfaces. Biofilm 2021; 3:100060. [PMID: 34841245 PMCID: PMC8605384 DOI: 10.1016/j.bioflm.2021.100060] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 11/02/2021] [Accepted: 11/03/2021] [Indexed: 11/24/2022] Open
Abstract
Biofilms enable bacteria to colonize numerous ecological niches. Bacteria within a biofilm are protected by the extracellular matrix (ECM), of which the fibril-forming amyloid protein curli and polysaccharide cellulose are major components in members of Salmonella, Eschericha and Mycobacterium genus. A shortage of real-time detection methods has limited our understanding of how ECM production contributes to biofilm formation and pathogenicity. Here we present optotracing as a new semi-high throughput method for dynamic monitoring of Salmonella biofilm growth on air-solid interfaces. We show how an optotracer with binding-induced fluorescence acts as a dynamic fluorescent reporter of curli expression during biofilm formation on agar. Using spectrophotometry and microscopic imaging of fluorescence, we analyse in real-time the development of the curli architecture in relation to bacterial cells. With exceptional spatial and temporal precision, this revealed a well-structured, non-uniform distribution of curli organised in distally projecting radial channel patterns. Dynamic monitoring of the biofilm also showed defined regions undergoing different growth phases. ECM structures were found to assemble in regions of late exponential growth phase, suggesting that ECM forms on site after bacteria colonize the surface. As the optotracer biofilm method expedites screening of curli production, providing exceptional spatial-temporal understanding of the surface-associated biofilm lifestyle, this method adds a new technique to further our understanding of bacterial biofilms. Design and evaluation of a method for real-time biofilm experimentation. Optotracing enables real-time monitoring of biofilm formation on solid supports. Definitive biofilm monitoring by selective tracking of ECM components. A method reducing the inherent biases of morphotyping. A semi-high throughput method increasing the ease and efficiency of biofilm detection.
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Affiliation(s)
- Ferdinand X Choong
- AIMES - Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden.,Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Smilla Huzell
- AIMES - Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden.,Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Ming Rosenberg
- AIMES - Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden.,Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Johannes A Eckert
- AIMES - Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden.,Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Madhu Nagaraj
- iNANO and Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Tianqi Zhang
- AIMES - Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden.,Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Keira Melican
- AIMES - Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden.,Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Daniel E Otzen
- iNANO and Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Agneta Richter-Dahlfors
- AIMES - Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden.,Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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Głazowska S, Mravec J. An aptamer highly specific to cellulose enables the analysis of the association of cellulose with matrix cell wall polymers in vitro and in muro. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 108:579-599. [PMID: 34314513 DOI: 10.1111/tpj.15442] [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: 04/21/2021] [Revised: 06/27/2021] [Accepted: 07/20/2021] [Indexed: 06/13/2023]
Abstract
The current toolbox of cell wall-directed molecular probes has been pivotal for advancing basic and application-oriented plant carbohydrate research; however, it still exhibits limitations regarding target diversity and specificity. Scarcity of probes targeting intramolecular associations between cell wall polymers particularly hinders our understanding of the cell wall microstructure and affects the development of effective means for its efficient deconstruction for bioconversion. Here we report a detailed characterization of a cellulose-binding DNA aptamer CELAPT MINI using a combination of various in vitro biochemical, biophysical, and molecular biology techniques. Our results show evidence for its high specificity towards long non-substituted β-(1-4)-glucan chains in both crystalline and amorphous forms. Fluorescent conjugates of CELAPT MINI are applicable as in situ cellulose probes and are well suited for various microscopy techniques, including super-resolution imaging. Compatibility of fluorescent CELAPT MINI variants with immunodetection of cell wall matrix polymers enabled them simultaneously to resolve the fibrillar organization of complex cellulose-enriched pulp material and to quantify the level of cellulose masking by xyloglucan and xylan. Using enzymatically, chemically, or genetically modulated Brachypodium internode sections we showed the diversity in cell wall packing among various cell types and even cell wall microdomains. We showed that xylan is the most prominent, but not the only, cellulose-masking agent in Brachypodium internode tissues. These results collectively highlight the hitherto unexplored potential to expand the cell wall probing toolbox with highly specific and versatile in vitro generated polynucleotide probes.
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Affiliation(s)
- Sylwia Głazowska
- Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Frederiksberg, DK-1871, Denmark
| | - Jozef Mravec
- Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Frederiksberg, DK-1871, Denmark
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DeVree BT, Steiner LM, Głazowska S, Ruhnow F, Herburger K, Persson S, Mravec J. Current and future advances in fluorescence-based visualization of plant cell wall components and cell wall biosynthetic machineries. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:78. [PMID: 33781321 PMCID: PMC8008654 DOI: 10.1186/s13068-021-01922-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 03/05/2021] [Indexed: 05/18/2023]
Abstract
Plant cell wall-derived biomass serves as a renewable source of energy and materials with increasing importance. The cell walls are biomacromolecular assemblies defined by a fine arrangement of different classes of polysaccharides, proteoglycans, and aromatic polymers and are one of the most complex structures in Nature. One of the most challenging tasks of cell biology and biomass biotechnology research is to image the structure and organization of this complex matrix, as well as to visualize the compartmentalized, multiplayer biosynthetic machineries that build the elaborate cell wall architecture. Better knowledge of the plant cells, cell walls, and whole tissue is essential for bioengineering efforts and for designing efficient strategies of industrial deconstruction of the cell wall-derived biomass and its saccharification. Cell wall-directed molecular probes and analysis by light microscopy, which is capable of imaging with a high level of specificity, little sample processing, and often in real time, are important tools to understand cell wall assemblies. This review provides a comprehensive overview about the possibilities for fluorescence label-based imaging techniques and a variety of probing methods, discussing both well-established and emerging tools. Examples of applications of these tools are provided. We also list and discuss the advantages and limitations of the methods. Specifically, we elaborate on what are the most important considerations when applying a particular technique for plants, the potential for future development, and how the plant cell wall field might be inspired by advances in the biomedical and general cell biology fields.
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Affiliation(s)
- Brian T DeVree
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark
| | - Lisa M Steiner
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark
| | - Sylwia Głazowska
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark
| | - Felix Ruhnow
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark
| | - Klaus Herburger
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark
| | - Staffan Persson
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark
- Joint International Research Laboratory of Metabolic and Developmental Sciences, State Key Laboratory of Hybrid Rice, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Jozef Mravec
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark
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Parlak O, Richter-Dahlfors A. Bacterial Sensing and Biofilm Monitoring for Infection Diagnostics. Macromol Biosci 2020; 20:e2000129. [PMID: 32588553 DOI: 10.1002/mabi.202000129] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/01/2020] [Indexed: 12/21/2022]
Abstract
Recent insights into the rapidly emerging field of bacterial sensing and biofilm monitoring for infection diagnostics are discussed as well as recent key developments and emerging technologies in the field. Electrochemical sensing of bacteria and bacterial biofilm via synthetic, natural, and engineered recognition, as well as direct redox-sensing approaches via algorithm-based optical sensing, and tailor-made optotracing technology are discussed. These technologies are highlighted to answer the very critical question: "how can fast and accurate bacterial sensing and biofilm monitoring be achieved? Following on from that: "how can these different sensing concepts be translated for use in infection diagnostics? A central obstacle to this transformation is the absence of direct and fast analysis methods that provide high-throughput results and bio-interfaces that can control and regulate the means of communication between biological and electronic systems. Here, the overall progress made to date in building such translational efforts at the level of an individual bacterial cell to a bacterial community is discussed.
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Affiliation(s)
- Onur Parlak
- AIMES-Center for the Advancement of Integrated Medical and Engineering Science, Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, SE-171 77, Sweden.,Department of Neuroscience, Karolinska Institutet, Stockholm, SE-171 77, Sweden
| | - Agneta Richter-Dahlfors
- AIMES-Center for the Advancement of Integrated Medical and Engineering Science, Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, SE-171 77, Sweden.,Department of Neuroscience, Karolinska Institutet, Stockholm, SE-171 77, Sweden.,Fibre and Polymer Technology, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
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8
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Design of novel well-defined oligothiophenes bearing donor-acceptor groups (pyrene-porphyrin): Synthesis, characterization, optical properties and energy transfer. J Mol Struct 2019. [DOI: 10.1016/j.molstruc.2019.01.078] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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9
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Wang B, Queenan BN, Wang S, Nilsson KPR, Bazan GC. Precisely Defined Conjugated Oligoelectrolytes for Biosensing and Therapeutics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1806701. [PMID: 30698856 DOI: 10.1002/adma.201806701] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 11/25/2018] [Indexed: 06/09/2023]
Abstract
Conjugated oligoelectrolytes (COEs) are a relatively new class of synthetic organic molecules with, as of yet, untapped potential for use in organic optoelectronic devices and bioelectronic systems. COEs also offer a novel molecular approach to biosensing, bioimaging, and disease therapy. Substantial progress has been made in the past decade at the intersection of chemistry, materials science, and the biological sciences developing COEs and their polymer analogues, namely, conjugated polyelectrolytes (CPEs), into synthetic systems with biological and biomedical utility. CPEs have traditionally attracted more attention in arenas of sensing, imaging, and therapy. However, the precisely defined molecular structures and interactions of COEs offer potential key advantages over CPEs, including higher reliability and fluorescence quantum efficiency, larger diversity of subcellular targeting strategies, and improved selectivity to biomolecules. Here, the unique-and sometimes overlooked-properties of COEs are discussed and the noticeable progress in their use for biological sensing, imaging, and therapy is reviewed.
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Affiliation(s)
- Bing Wang
- Center for Polymers and Organic Solids, Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106, USA
| | - Bridget N Queenan
- Department of Mechanical Engineering, Neuroscience Research Institute, University of California, Santa Barbara, CA, 93106, USA
| | - Shu Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - K Peter R Nilsson
- Division of Chemistry, Department of Physics, Chemistry and Biology, Linköping University, Linköping, SE, -581 83, Sweden
| | - Guillermo C Bazan
- Center for Polymers and Organic Solids, Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106, USA
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Löffler S, Antypas H, Choong FX, Nilsson KPR, Richter-Dahlfors A. Conjugated Oligo- and Polymers for Bacterial Sensing. Front Chem 2019; 7:265. [PMID: 31058140 PMCID: PMC6482434 DOI: 10.3389/fchem.2019.00265] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 04/01/2019] [Indexed: 11/29/2022] Open
Abstract
Fast and accurate detection of bacteria and differentiation between pathogenic and commensal colonization are important keys in preventing the emergence and spread of bacterial resistance toward antibiotics. As bacteria undergo major lifestyle changes during colonization, bacterial sensing needs to be achieved on different levels. In this review, we describe how conjugated oligo- and polymers are used to detect bacterial colonization. We summarize how oligothiophene derivatives have been tailor-made for detection of biopolymers produced by a wide range of bacteria upon entering the biofilm lifestyle. We further describe how these findings are translated into diagnostic approaches for biofilm-related infections. Collectively, this provides an overview on how synthetic biorecognition elements can be used to produce fast and easy diagnostic tools and new methods for infection control.
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Affiliation(s)
- Susanne Löffler
- Department of Neuroscience, Swedish Medical Nanoscience Center, Karolinska Institutet, Stockholm, Sweden
| | - Haris Antypas
- Department of Neuroscience, Swedish Medical Nanoscience Center, Karolinska Institutet, Stockholm, Sweden
| | - Ferdinand X. Choong
- Department of Neuroscience, Swedish Medical Nanoscience Center, Karolinska Institutet, Stockholm, Sweden
| | | | - Agneta Richter-Dahlfors
- Department of Neuroscience, Swedish Medical Nanoscience Center, Karolinska Institutet, Stockholm, Sweden
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Rapid diagnostic assay for detection of cellulose in urine as biomarker for biofilm-related urinary tract infections. NPJ Biofilms Microbiomes 2018; 4:26. [PMID: 30393563 PMCID: PMC6203724 DOI: 10.1038/s41522-018-0069-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 09/29/2018] [Accepted: 10/09/2018] [Indexed: 11/09/2022] Open
Abstract
The ability of uropathogenic Escherichia coli (UPEC) to adopt a biofilm lifestyle in the urinary tract is suggested as one cause of recurrent urinary tract infections (UTIs). A clinical role of UPEC biofilm is further supported by the presence of bacterial aggregates in urine of UTI patients. Yet, no diagnostics exist to differentiate between the planktonic and biofilm lifestyle of bacteria. Here, we developed a rapid diagnostic assay for biofilm-related UTI, based on the detection of cellulose in urine. Cellulose, a component of biofilm extracellular matrix, is detected by a luminescent-conjugated oligothiophene, which emits a conformation-dependent fluorescence spectrum when bound to a target molecule. We first defined the cellulose-specific spectral signature in the extracellular matrix of UPEC biofilm colonies, and used these settings to detect cellulose in urine. To translate this optotracing assay for clinical use, we composed a workflow that enabled rapid isolation of urine sediment and screening for the presence of UPEC-derived cellulose in <45 min. Using multivariate analysis, we analyzed spectral information obtained between 464 and 508 nm by optotracing of urine from 182 UTI patients and 8 healthy volunteers. Cellulose was detected in 14.8% of UTI urine samples. Using cellulose as a biomarker for biofilm-related UTI, our data provide direct evidence that UPEC forms biofilm in the urinary tract. Clinical implementation of this rapid, non-invasive and user-friendly optotracing diagnostic assay will potentially aid clinicians in the design of effective antibiotic treatment.
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