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Uchiyama H, Kudo T, Yamaguchi T, Obana N, Watanabe K, Abe K, Miyazaki H, Toyofuku M, Nomura N, Akeda Y, Nakao R. Mucosal adjuvanticity and mucosal booster effect of colibactin-depleted probiotic Escherichia coli membrane vesicles. Hum Vaccin Immunother 2024; 20:2337987. [PMID: 38658133 PMCID: PMC11057659 DOI: 10.1080/21645515.2024.2337987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 03/29/2024] [Indexed: 04/26/2024] Open
Abstract
There is a growing interest in development of novel vaccines against respiratory tract infections, due to COVID-19 pandemic. Here, we examined mucosal adjuvanticity and the mucosal booster effect of membrane vesicles (MVs) of a novel probiotic E. coli derivative lacking both flagella and potentially carcinogenic colibactin (ΔflhDΔclbP). ΔflhDΔclbP-derived MVs showed rather strong mucosal adjuvanticity as compared to those of a single flagellar mutant strain (ΔflhD-MVs). In addition, glycoengineered ΔflhDΔclbP-MVs displaying serotype-14 pneumococcal capsular polysaccharide (CPS14+MVs) were well-characterized based on biological and physicochemical parameters. Subcutaneous (SC) and intranasal (IN) booster effects of CPS14+MVs on systemic and mucosal immunity were evaluated in mice that have already been subcutaneously prime-immunized with the same MVs. With a two-dose regimen, an IN boost (SC-IN) elicited stronger IgA responses than homologous prime-boost immunization (SC-SC). With a three-dose regimen, serum IgG levels were comparable among all tested regimens. Homologous immunization (SC-SC-SC) elicited the highest IgM responses among all regimens tested, whereas SC-SC-SC failed to elicit IgA responses in blood and saliva. Furthermore, serum IgA and salivary SIgA levels were increased with an increased number of IN doses administrated. Notably, SC-IN-IN induced not only robust IgG response, but also the highest IgA response in both serum and saliva among the groups. The present findings suggest the potential of a heterologous three-dose administration for building both systemic and mucosal immunity, e.g. an SC-IN-IN vaccine regimen could be beneficial. Another important observation was abundant packaging of colibactin in MVs, suggesting increased applicability of ΔflhDΔclbP-MVs in the context of vaccine safety.
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Affiliation(s)
- Hiroki Uchiyama
- Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
- Department of Vascular Surgery, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
| | - Toshifumi Kudo
- Department of Vascular Surgery, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
| | - Takehiro Yamaguchi
- Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Nozomu Obana
- Tsukuba Transborder Medical Research Center, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
- Microbiology Research Center for Sustainability, University of Tsukuba, Tsukuba, Japan
| | - Kenji Watanabe
- Department of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
| | - Kimihiro Abe
- Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
- Research Center for Drug and Vaccine Development, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Hidetaka Miyazaki
- Department of Oculoplastic, Orbital and Lacrimal Surgery, Aichi Medical University, Nagakute, Japan
- Department of Oral and Maxillofacial Surgery, Division of Oral Health Sciences, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
| | - Masanori Toyofuku
- Microbiology Research Center for Sustainability, University of Tsukuba, Tsukuba, Japan
| | - Nobuhiko Nomura
- Microbiology Research Center for Sustainability, University of Tsukuba, Tsukuba, Japan
| | - Yukihiro Akeda
- Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Ryoma Nakao
- Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
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García-Bayona L, Said N, Coyne MJ, Flores K, Elmekki NM, Sheahan ML, Camacho AG, Hutt K, Yildiz FH, Kovács ÁT, Waldor MK, Comstock LE. A pervasive large conjugative plasmid mediates multispecies biofilm formation in the intestinal microbiota increasing resilience to perturbations. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.29.590671. [PMID: 38746121 PMCID: PMC11092513 DOI: 10.1101/2024.04.29.590671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Although horizontal gene transfer is pervasive in the intestinal microbiota, we understand only superficially the roles of most exchanged genes and how the mobile repertoire affects community dynamics. Similarly, little is known about the mechanisms underlying the ability of a community to recover after a perturbation. Here, we identified and functionally characterized a large conjugative plasmid that is one of the most frequently transferred elements among Bacteroidales species and is ubiquitous in diverse human populations. This plasmid encodes both an extracellular polysaccharide and fimbriae, which promote the formation of multispecies biofilms in the mammalian gut. We use a hybridization-based approach to visualize biofilms in clarified whole colon tissue with unprecedented 3D spatial resolution. These biofilms increase bacterial survival to common stressors encountered in the gut, increasing strain resiliency, and providing a rationale for the plasmid's recent spread and high worldwide prevalence.
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Nakao R, Hirayama S, Yamaguchi T, Senpuku H, Hasegawa H, Suzuki T, Akeda Y, Ohnishi M. A bivalent outer membrane vesicle-based intranasal vaccine to prevent infection of periodontopathic bacteria. Vaccine 2023; 41:4369-4383. [PMID: 37302966 DOI: 10.1016/j.vaccine.2023.05.058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 04/30/2023] [Accepted: 05/25/2023] [Indexed: 06/13/2023]
Abstract
Periodontal disease has become a serious public health problem, not only causing tooth loss, but also inducing chronic disorders of extra-oral organs. The present study assessed an intranasal vaccine strategy to prevent periodontal disease using outer membrane vesicles (OMVs) of two major periodontopathic bacteria, Porphyromonas gingivalis (Pg) and Aggregatibacter actinomycetemcomitans (Aa). We compared the morphology, composition, and immune activity between OMVs of Pg strain ATCC 33277 and Aa strain Y4. Aa OMVs had a smoother surface and stronger lipid A activity compared to Pg OMVs. The in vitro immune activity elicited by Aa OMVs in macrophage-like cells was remarkably stronger than that of Pg OMVs. Intranasal immunization of mice with Aa OMVs alone resulted in robust, humoral immune responses in blood and saliva. Despites the intrinsically low mucosal immunogenicity of Pg OMVs alone, using Aa OMVs as a mucosal adjuvant strongly enhanced Pg-specific immune responses, resulting in both serum IgG and salivary IgA, both of which aggregated Pg and Aa cells. Furthermore, Aa OMVs were found to be a more potent mucosal adjuvant than Poly(I:C) in the context of enhancing the production of Pg-specific IgG (especially IgG2a) and IgA. In addition, in a randomized, blinded study, mice oral challenged with Pg and Aa after intranasal immunization with Pg OMVs and Aa OMVs had significantly decreased numbers of both microorganisms compared to mock-immunized mice. Furthermore, in an intracerebral injection mouse model, there were no serious adverse effects on the brain even after administrating a dose of OMVs as same as that used for intranasal administration. Taken together, the bivalent OMV intranasal vaccine may be effective in preventing colonization of periodontopathic bacteria in the oral cavity and related systemic disorders associated with periodontal diseases.
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Affiliation(s)
- Ryoma Nakao
- Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo 162-8640, Japan.
| | - Satoru Hirayama
- Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo 162-8640, Japan; Division of Microbiology and Infectious Diseases, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8514, Japan
| | - Takehiro Yamaguchi
- Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
| | - Hidenobu Senpuku
- Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo 162-8640, Japan; Department of Microbiology and Immunology, School of Dentistry at Matsudo, Nihon University, Chiba 271-8587, Japan
| | - Hideki Hasegawa
- Department of Influenza Virus Research Center, National Institute of Infectious Diseases, Tokyo 208-0011, Japan
| | - Tadaki Suzuki
- Department of Pathology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
| | - Yukihiro Akeda
- Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
| | - Makoto Ohnishi
- Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
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Alshammari M, Ahmad A, AlKhulaifi M, Al Farraj D, Alsudir S, Alarawi M, Takashi G, Alyamani E. Reduction of biofilm formation of Escherichia coli by targeting quorum sensing and adhesion genes using the CRISPR/Cas9-HDR approach, and its clinical application on urinary catheter. J Infect Public Health 2023; 16:1174-1183. [PMID: 37271098 DOI: 10.1016/j.jiph.2023.05.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 04/07/2023] [Accepted: 05/21/2023] [Indexed: 06/06/2023] Open
Abstract
BACKGROUND Escherichia coli is a common cause of biofilm-associated urinary tract infections (UTIs). Biofilm formation in E. coli is responsible for various indwelling medical device-associated infections, including catheter-associated urinary tract infections (CAUTIs). This study aimed to reduce biofilm formation of E. coli ATCC 25922 by knocking out genes involved in quorum sensing (QS) (luxS) and adhesion (fimH and bolA) using the CRISPR/Cas9-HDR approach. METHOD Single-guide RNAs (sgRNAs) were designed to target luxS, fimH and bolA genes. Donor DNA for homologous recombination was constructed to provide accurate repairs of double-strand breaks (DSBs). A biofilm quantification assay (crystal violet assay) was performed to quantify the biofilm formation of mutant and wild-type strains. Morphological changes in biofilm architecture were confirmed by scanning electron microscopy (SEM). Further application of the biofilm formation of mutant and wild-type strains on urinary catheter was tested. RESULTS Crystal violet assay showed that the biofilm formation of ΔfimH, ΔluxS, and ΔbolA strains was significantly reduced compared to the wild-type strain (P value < 0.001). The percentage of biofilm reduction of mutant strains was as follows: ΔluxS1 77.51 %, ΔfimH1 78.37 %, ΔfimH2 84.17 %, ΔbolA1 78.24 %, and ΔbolA2 75.39 %. Microscopic analysis showed that all mutant strains lack extracellular polymeric substances (EPS) production compared to the wild-type strain, which was embedded in its EPS matrix. The adherence, cell aggregation, and biofilm formation of wild-type strain on urinary catheters were significantly higher compared to ΔfimH, ΔluxS and ΔbolA strains. CONCLUSION Altogether, our results demonstrated that the knockout of luxS, fimH, and bolA genes reduced EPS matrix production, which is considered the main factor in the development, maturation, and maintenance of the integrity of biofilm. This pathway could be a potential strategy to disrupt E. coli biofilm-associated UTIs. This study suggests that CRISPR/Cas9-HDR system may provide an efficient and site-specific gene editing approach that exhibits a possible antibiofilm strategy through intervention with the QS mechanism and adhesion property to suppress biofilm formation associated with UTI catheter infections.
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Affiliation(s)
- Maryam Alshammari
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
| | - Aldossary Ahmad
- Wellness and Preventive Medicine Institue, Health Sector, King Abdulaziz city for Science and Technology, Riyadh 11442, Saudi Arabia..
| | - Manal AlKhulaifi
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
| | - Dunia Al Farraj
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
| | - Samar Alsudir
- Wellness and Preventive Medicine Institue, Health Sector, King Abdulaziz city for Science and Technology, Riyadh 11442, Saudi Arabia.; Bioengineering institute, Health Sector, King Abdulaziz city for Science and Technology, Riyadh 11442, Saudi Arabia..
| | - Moahmed Alarawi
- Computational Bioscience Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia.
| | - Gojobori Takashi
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955, Saudi Arabia.
| | - Essam Alyamani
- Wellness and Preventive Medicine Institue, Health Sector, King Abdulaziz city for Science and Technology, Riyadh 11442, Saudi Arabia..
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Nakao R, Kobayashi H, Iwabuchi Y, Kawahara K, Hirayama S, Ramstedt M, Sasaki Y, Kataoka M, Akeda Y, Ohnishi M. A highly immunogenic vaccine platform against encapsulated pathogens using chimeric probiotic Escherichia coli membrane vesicles. NPJ Vaccines 2022; 7:153. [PMID: 36435869 PMCID: PMC9701205 DOI: 10.1038/s41541-022-00572-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 11/03/2022] [Indexed: 11/28/2022] Open
Abstract
Vaccines against infectious diseases should elicit potent and long-lasting immunity, ideally even in those with age-related decline in immune response. Here we report a rational polysaccharide vaccine platform using probiotic Escherichia coli-derived membrane vesicles (MVs). First, we constructed a probiotic E. coli clone harboring the genetic locus responsible for biogenesis of serotype 14 pneumococcal capsular polysaccharides (CPS14) as a model antigen. CPS14 was found to be polymerized and mainly localized on the outer membrane of the E. coli cells. The glycine-induced MVs displayed the exogenous CPS14 at high density on the outermost surface, on which the CPS14 moiety was covalently tethered to a lipid A-core oligosaccharide anchor. In in vivo immunization experiments, CPS14+MVs, but not a mixture of free CPS14 and empty MVs, strongly elicited IgG class-switch recombination with a Th1/Th2-balanced IgG subclass distribution without any adjuvant. In addition, CPS14+MVs were structurally stable with heat treatment and immunization with the heat-treated MVs-elicited CPS14-specific antibody responses in mouse serum to levels comparable to those of non-treated CPS14+MVs. Notably, the immunogenicity of CPS14+MVs was significantly stronger than those of two currently licensed vaccines against pneumococci. The CPS14+MV-elicited humoral immune responses persisted for 1 year in both blood and lung. Furthermore, the CPS14+MV vaccine was widely efficacious in mice of different ages. Even in aged mice, vaccination resulted in robust production of CPS14-specific IgG that bound to the pneumococcal cell surface. Taken together, the present probiotic E. coli MVs-based vaccine platform offers a promising, generalizable solution against encapsulated pathogens.
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Affiliation(s)
- Ryoma Nakao
- Department of Bacteriology I, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan.
| | - Hirotaka Kobayashi
- Department of Pathology, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan
| | - Yusuke Iwabuchi
- Department of Bacteriology I, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan.,Department of Pediatric Dentistry/Special Needs Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan
| | - Kazuyoshi Kawahara
- College of Science and Engineering, Kanto Gakuin University, 1-50-1, Mutsuura-higashi, Kanazawa-ku, Yokohama, Kanagawa, 236-8501, Japan
| | - Satoru Hirayama
- Department of Bacteriology I, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan.,Division of Microbiology and Infectious Diseases, Niigata University Graduate School of Medical and Dental Sciences, 2-5274, Gakkocho-dori, Chuo-ku, Niigata, 951-8514, Japan
| | - Madeleine Ramstedt
- Department of Chemistry, Umeå Centre for Microbial Research (UCMR), Umeå University, SE-901 87, Umeå, Sweden
| | - Yuki Sasaki
- Nanostructures Research Laboratory, Japan Fine Ceramics Center, 2-4-1 Mutsuno, Atsuta-ku, Nagoya, 456-8587, Japan
| | - Michiyo Kataoka
- Department of Pathology, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan
| | - Yukihiro Akeda
- Department of Bacteriology I, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan
| | - Makoto Ohnishi
- National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan
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Mechanical, Structural, and Biological Characteristics of Polylactide/Wollastonite 3D Printed Scaffolds. Polymers (Basel) 2022; 14:polym14193932. [PMID: 36235880 PMCID: PMC9572193 DOI: 10.3390/polym14193932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 09/13/2022] [Accepted: 09/15/2022] [Indexed: 11/17/2022] Open
Abstract
The present work aimed to study the synergistic response of bioresorbable polylactide/bioactive wollastonite scaffolds towards mechanical stability, mesenchymal stromal cell colonization, and antibacterial activity in the physiological environment. Wollastonite was synthesized at 800 °C within 2 h by sol-gel combustion method. The surface area was found to be 1.51 m2/g, and Transmission Electron Microscopy (TEM) micrographs indicated the presence of porous structures. Fused deposition modeling was used to prepare 3D-printed polylactide/wollastonite and polylactide/hydroxyapatite scaffolds. Scanning Electron Microscopy (SEM) micrographs confirmed the interconnected porous structure and complex geometry of the scaffolds. The addition of wollastonite decreased the contact angle of the scaffolds. The mechanical testing of scaffolds examined by computational simulation, as well as machine testing, revealed their non-load-bearing capacity. The chemical constituent of the scaffolds was found to influence the attachment response of different cells on their surface. The incorporation of wollastonite effectively reduced live bacterial attachment, whereas the colonization of mesenchymal cells was improved. This observation confirms polylactide/wollastonite scaffold possesses both bactericidal as well as cytocompatible properties. Thus, the risk of peri-implant bacterial film formation can be prevented, and the biological fixation of the scaffold at the defect site can be enhanced by utilizing these composites.
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Flores-Vargas G, Bergsveinson J, Lawrence JR, Korber DR. Environmental Biofilms as Reservoirs for Antimicrobial Resistance. Front Microbiol 2022; 12:766242. [PMID: 34970233 PMCID: PMC8713029 DOI: 10.3389/fmicb.2021.766242] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 11/22/2021] [Indexed: 12/17/2022] Open
Abstract
Characterizing the response of microbial communities to a range of antibiotic concentrations is one of the strategies used to understand the impact of antibiotic resistance. Many studies have described the occurrence and prevalence of antibiotic resistance in microbial communities from reservoirs such as hospitals, sewage, and farm feedlots, where bacteria are often exposed to high and/or constant concentrations of antibiotics. Outside of these sources, antibiotics generally occur at lower, sub-minimum inhibitory concentrations (sub-MICs). The constant exposure to low concentrations of antibiotics may serve as a chemical "cue" that drives development of antibiotic resistance. Low concentrations of antibiotics have not yet been broadly described in reservoirs outside of the aforementioned environments, nor is the transfer and dissemination of antibiotic resistant bacteria and genes within natural microbial communities fully understood. This review will thus focus on low antibiotic-concentration environmental reservoirs and mechanisms that are important in the dissemination of antibiotic resistance to help identify key knowledge gaps concerning the environmental resistome.
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Affiliation(s)
| | | | - John R Lawrence
- Environment and Climate Change Canada, Saskatoon, SK, Canada
| | - Darren R Korber
- Food and Bioproduct Sciences, University of Saskatchewan, Saskatoon, SK, Canada
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Lee IPA, Eldakar OT, Gogarten JP, Andam CP. Bacterial cooperation through horizontal gene transfer. Trends Ecol Evol 2021; 37:223-232. [PMID: 34815098 DOI: 10.1016/j.tree.2021.11.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/27/2021] [Accepted: 11/01/2021] [Indexed: 11/16/2022]
Abstract
Cooperation exists across all scales of biological organization, from genetic elements to complex human societies. Bacteria cooperate by secreting molecules that benefit all individuals in the population (i.e., public goods). Genes associated with cooperation can spread among strains through horizontal gene transfer (HGT). We discuss recent findings on how HGT mediated by mobile genetic elements promotes bacterial cooperation, how cooperation in turn can facilitate more frequent HGT, and how the act of HGT itself may be considered as a form of cooperation. We propose that HGT is an important enforcement mechanism in bacterial populations, thus creating a positive feedback loop that further maintains cooperation. To enforce cooperation, HGT serves as a homogenizing force by transferring the cooperative trait, effectively eliminating cheaters.
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Affiliation(s)
- Isaiah Paolo A Lee
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, USA
| | - Omar Tonsi Eldakar
- Department of Biological Sciences, Nova Southeastern University, Fort Lauderdale, FL 33314, USA
| | - J Peter Gogarten
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, USA.
| | - Cheryl P Andam
- Department of Biological Sciences, University at Albany, State University of New York, Albany, NY 12222, USA.
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Chadha J. In vitro effects of sub-inhibitory concentrations of amoxicillin on physiological responses and virulence determinants in a commensal strain of Escherichia coli. J Appl Microbiol 2021; 131:682-694. [PMID: 33387370 DOI: 10.1111/jam.14987] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 12/14/2020] [Accepted: 12/26/2020] [Indexed: 02/06/2023]
Abstract
AIMS The goal was to study the effects of sub-minimum inhibitory concentrations (sub-MICs) of amoxicillin (AMX) on various physiological responses and virulence determinants in a commensal strain of Escherichia coli. MATERIALS AND RESULTS The commensal strain was passaged under various sub-MICs of AMX and its effect on bacterial growth, motility, biofilm formation, expression of outer membrane proteins (OMPs) and cell adhesion was analysed. Bacterial growth was diminished at 1/2 and 1/4 MICs of AMX with significant reduction in growth rate. Using crystal violet (CV) assays and quantification of surface polysaccharides we observed strong biofilm formation, together with reduced swimming motility in E. coli at 1/2 MIC of AMX. Differential OMP expression upon AMX sub-MIC exposure coincided with enhanced cell adhesion to HT-29 cells in vitro. The results demonstrated that sub-MICs of AMX can stimulate unpredictable changes in commensal bacterial strains which can be a potent source for the propagation of antibiotic resistance. CONCLUSIONS The study reports that AMX at 1/2 MIC significantly compromised bacterial growth and swimming motility, alongside inducing biofilm formation. This was also accompanied by upregulation of a single OMP which subsequently increased cell adhesion capabilities in E. coli at 1/2 MIC, thereby enhancing its colonization and survival abilities within the gut microsphere. SIGNIFICANCE AND IMPACT OF THE STUDY For the first time, the effects of AMX sub-MICs on a commensal E. coli strain were described. The results corroborate on how antibiotics can act as stimulatory molecules and determine the pathogenicity of commensal bacteria in vivo that can disseminate resistance to other intestinal pathogens or microbes.
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Affiliation(s)
- J Chadha
- Department of Microbiology, University of Delhi South Campus, New Delhi, India
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10
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Gong H, He L, Zhao Z, Mao X, Zhang C. The specific effect of (R)-(+)-pulegone on growth and biofilm formation in multi-drug resistant Escherichia coli and molecular mechanisms underlying the expression of pgaABCD genes. Biomed Pharmacother 2021; 134:111149. [PMID: 33385683 DOI: 10.1016/j.biopha.2020.111149] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/29/2020] [Accepted: 12/14/2020] [Indexed: 01/11/2023] Open
Abstract
E. coli is associated with high rates of infection and resistance to drugs not only in China but also the rest of the world. In addition, the number of E. coli biofilm infections continue to increase with time. Notably, biofilms are attractive targets for the prevention of infections caused by multidrug-resistant bacteria. Moreover, the pgaABCD-encoded Poly-β-1,6-N-acetyl-d-glucosamine (PNAG) plays an important role in biofilm formation. Therefore, this study aimed to explore the specific effect of the (R)-(+)-pulegone (PU) on growth and biofilm formation in multi-drug resistant E. coli. The molecular mechanisms involved were also examined. The results showed that PU had significant antibacterial and antibiofilm formation activity against E. coli K1, with MIC and MBC values of 23.68 and 47.35 mg/mL, respectively. On the other hand, the maximum inhibition rate for biofilm formation in the bacterium was 52.36 % at 94.70 mg/mL of PU. qRT-PCR data showed that PU significantly down-regulated expression of the pgaABCD genes (P < 0.05). PU was also broadly effective against biofilm formation in MG1655 and MG1655/ΔpgaABCD, exhibiting the maximum inhibition rates were 98.23 % and 93.35 %, respectively. In addition, PU destroyed pre-formed mature biofilm in both MG1655 and MG1655/ΔpgaABCD about 95.03 % and 92.4 %, respectively. The study therefore verified that pgaA was a potential and key target for PU in E. coli although it was not the only one. Overall, the findings indicated that PU is a potential and novel inhibitor of drug resistance, This therefore gives insights on new ways of preventing and treating biofilm-associated infections in the food industry as well as in clinical practice.
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Affiliation(s)
- Haiyan Gong
- The Fifth Affiliated Hospital of Xinjiang Medical University, Xinshi District, No. 118 Henan West Road, Urumqi, Xinjiang, PR China.
| | - Lijuan He
- College of Public Health of Xinjiang Medical University, Shuimogou District, No. 567 Shangde North Road, Urumqi, Xinjiang, PR China.
| | - Zhilong Zhao
- The Fifth Affiliated Hospital of Xinjiang Medical University, Xinshi District, No. 118 Henan West Road, Urumqi, Xinjiang, PR China.
| | - Xinmin Mao
- College of Traditional Chinese Medicine, Key Discipline of Integrated Traditional Chinese and Western Medicine of Autonomous Region from Xinjiang Medical University, Shuimogou District, No. 567 Shangde North Road, Urumqi, Xinjiang, PR China.
| | - Chen Zhang
- Xinjiang Medical University, Shuimogou District, No. 567 Shangde North Road, Urumqi, Xinjiang, PR China.
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11
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Abstract
The release of extracellular vesicles (EVs) is a process conserved across the three domains of life. Amongst prokaryotes, EVs produced by Gram-negative bacteria, termed outer membrane vesicles (OMVs), were identified more than 50 years ago and a wealth of literature exists regarding their biogenesis, composition and functions. OMVs have been implicated in benefiting numerous metabolic functions of their parent bacterium. Additionally, OMVs produced by pathogenic bacteria have been reported to contribute to pathology within the disease setting. By contrast, the release of EVs from Gram-positive bacteria, known as membrane vesicles (MVs), has only been widely accepted within the last decade. As such, there is a significant disproportion in knowledge regarding MVs compared to OMVs. Here we provide an overview of the literature regarding bacterial membrane vesicles (BMVs) produced by pathogenic and commensal bacteria. We highlight the mechanisms of BMV biogenesis and their roles in assisting bacterial survival, in addition to discussing their functions in promoting disease pathologies and their potential use as novel therapeutic strategies.
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Affiliation(s)
- William J Gilmore
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, VIC, Australia
- Research Centre for Extracellular Vesicles, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
| | - Natalie J Bitto
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, VIC, Australia
- Research Centre for Extracellular Vesicles, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
| | - Maria Kaparakis-Liaskos
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, VIC, Australia.
- Research Centre for Extracellular Vesicles, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia.
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Abe K, Nomura N, Suzuki S. Biofilms: hot spots of horizontal gene transfer (HGT) in aquatic environments, with a focus on a new HGT mechanism. FEMS Microbiol Ecol 2020; 96:5766226. [PMID: 32109282 PMCID: PMC7189800 DOI: 10.1093/femsec/fiaa031] [Citation(s) in RCA: 165] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 02/27/2020] [Indexed: 12/21/2022] Open
Abstract
Biofilms in water environments are thought to be hot spots for horizontal gene transfer (HGT) of antibiotic resistance genes (ARGs). ARGs can be spread via HGT, though mechanisms are known and have been shown to depend on the environment, bacterial communities and mobile genetic elements. Classically, HGT mechanisms include conjugation, transformation and transduction; more recently, membrane vesicles (MVs) have been reported as DNA reservoirs implicated in interspecies HGT. Here, we review the current knowledge on the HGT mechanisms with a focus on the role of MVs and the methodological innovations in the HGT research.
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Affiliation(s)
- Kimihiro Abe
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, 305-8577 Japan
| | - Nobuhiko Nomura
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, 305-8577 Japan.,Microbiology Research Center for Sustainability, University of Tsukuba, Tsukuba, 305-8577 Japan
| | - Satoru Suzuki
- Center for Marine Environmental Studies, Ehime University, Matsuyama, 790-8577 Japan
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13
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Gama JA, Fredheim EGA, Cléon F, Reis AM, Zilhão R, Dionisio F. Dominance Between Plasmids Determines the Extent of Biofilm Formation. Front Microbiol 2020; 11:2070. [PMID: 32983050 PMCID: PMC7479130 DOI: 10.3389/fmicb.2020.02070] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 08/06/2020] [Indexed: 01/18/2023] Open
Abstract
Bacterial biofilms have an impact in medical and industrial environments because they often confer protection to bacteria against harmful agents, and constitute a source from which microorganisms can disperse. Conjugative plasmids can enhance bacterial ability to form biofilms because conjugative pili act as adhesion factors. However, plasmids may interact with each other, either facilitating or inhibiting plasmid transfer. Accordingly, we asked whether effects on plasmid transfer also impacts biofilm formation. We measured biofilm formation of Escherichia coli cells harboring two plasmid types, or when the two plasmids were present in the same population but carried in different cells. Using eleven natural isolated conjugative plasmids, we confirmed that some indeed promote biofilm formation and, importantly, that this ability is correlated with conjugative efficiency. Further we studied the effect of plasmid pairs on biofilm formation. We observed increased biofilm formation in approximately half of the combinations when both plasmids inhabited the same cell or when the plasmids were carried in different cells. Moreover, in approximately half of the combinations, independent of the co-inhabitation conditions, one of the plasmids alone determined the extent of biofilm formation – thus having a dominant effect over the other plasmid. The molecular mechanisms responsible for these interactions were not evaluated here and future research is required to elucidate them.
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Affiliation(s)
- João Alves Gama
- Department of Pharmacy, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
| | | | - François Cléon
- Department of Pharmacy, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway
| | - Ana Maria Reis
- Biosystems and Integrative Sciences Institute (BioISI), Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal.,Departamento de Biologia Vegetal, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Rita Zilhão
- Departamento de Biologia Vegetal, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Francisco Dionisio
- Departamento de Biologia Vegetal, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal.,Centre for Ecology, Evolution and Environmental Changes (cE3c), Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
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14
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Huang C, Liu LZ, Kong HK, Law COK, Hoa PQ, Ho PL, Lau TCK. A novel incompatibility group X3 plasmid carrying bla NDM-1 encodes a small RNA that regulates host fucose metabolism and biofilm formation. RNA Biol 2020; 17:1767-1776. [PMID: 32594845 DOI: 10.1080/15476286.2020.1780040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
The emergence of New Delhi metallo-beta-lactamase (NDM-1) has become a major health threat to clinical managements of gram-negative bacteria infections. A novel incompatibility group X3 plasmid (IncX3) pNDM-HN380 carrying bla NDM-1 has recently been found to epidemiologically link with multiple geographical areas in China. In this paper, we studied the metabolic responses of host bacteria E. coli J53 upon introduction of pNDM-HN380. A reduction of bacterial motility was observed in J53/pNDM-HN380. We profiled the RNA repertoires of the transconjugants and found a downregulation of genes involved in flagella and chemotaxis metabolic pathways at logarithmic (log) phase. We also identified a novel intragenic region (IGR) small RNA plas2. The plasmid-transcribed sRNA IGR plas2 was further characterized as a regulator of fucRwhich controls the fucose metabolism. By knockdown of IGR plas2 using an antisense decoy, we managed to inhibit the formation of bacterial biofilm of the host. Our study demonstrated a potential way of utilizing plasmid-transcribed sRNA against infectious bacteria.
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Affiliation(s)
- Chuan Huang
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong , Hong Kong, Hong Kong Special Administrative Region
| | - Liang-Zhe Liu
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong , Hong Kong, Hong Kong Special Administrative Region
| | - Hoi-Kuan Kong
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong , Hong Kong, Hong Kong Special Administrative Region
| | - Carmen O K Law
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong , Hong Kong, Hong Kong Special Administrative Region
| | - Pham Quynh Hoa
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong , Hong Kong, Hong Kong Special Administrative Region
| | - Pak-Leung Ho
- Department of Microbiology, The University of Hong Kong , Hong Kong, Hong Kong Special Administrative Region
| | - Terrence C K Lau
- Department of Biomedical Sciences, College of Veterinary Medicine and Life Science, City University of Hong Kong , Hong Kong, Hong Kong Special Administrative Region
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15
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Sarkar S. Release mechanisms and molecular interactions of Pseudomonas aeruginosa extracellular DNA. Appl Microbiol Biotechnol 2020; 104:6549-6564. [PMID: 32500267 DOI: 10.1007/s00253-020-10687-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 05/10/2020] [Accepted: 05/17/2020] [Indexed: 12/18/2022]
Abstract
Pseudomonas aeruginosa infection is a significant threat for clinicians. Increasing incidents of resistant biofilm infection result in high mortality rates worldwide. There is a considerable current interest in the field of extracellular DNA (eDNA)-mediated P. aeruginosa biofilm formation. eDNA acts as a glue to make biofilm more stable. This review focuses on the diverse mechanisms and factors, which enhance the eDNA release into the extracellular milieu. Furthermore, eDNA-mediated molecular interactions within the biofilm are emphasized. In addition, drug resistance mechanisms due to the versatility of eDNA are discussed. Spatial physiological diversity is expected due to different metabolic activity of bacterial subpopulation present in P. aeruginosa biofilm layers. In P. aeruginosa, eDNA release is accomplished by cell lysis and OMVs (outer membrane vesicles). eDNA release is a spontaneous and multifactorial process, which may be accomplished by PQS, pyocyanin, and lambda prophage induction. Hydrogen peroxide and pyocin trigger cell death, which may facilitate eDNA release. Lung mucosa of cystic fibrosis patients is enriched with eDNA, which acidifies biofilm and develops P. aeruginosa resistance to aminoglycosides. Further studies on spatial and molecular characterization of bacterial subpopulation in biofilm will shed light on eDNA-biofilm interaction more precisely.Key Points• Extracellular DNA (eDNA) is a key component of Pseudomonas aeruginosa biofilm.• P. aeruginosa eDNA acts as a glue to make biofilm more stronger.• Bacterial cell death or lysis may be the potential way to release P. aeruginosa eDNA into extracellular milieu.• P. aeruginosa eDNA contributes to develop resistance to antimicrobials.
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Affiliation(s)
- Subendu Sarkar
- Department of Surgery, University School of Medicine, Indiana University, Indianapolis, IN, 46202, USA. .,Department of Surgery, Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, 43210, USA.
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16
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The insect antimicrobial peptide cecropin A disrupts uropathogenic Escherichia coli biofilms. NPJ Biofilms Microbiomes 2020; 6:6. [PMID: 32051417 PMCID: PMC7016129 DOI: 10.1038/s41522-020-0116-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 01/15/2020] [Indexed: 12/11/2022] Open
Abstract
Current antibiotics cannot eradicate uropathogenic Escherichia coli (UPEC) biofilms, leading to recurrent urinary tract infections. Here, we show that the insect antimicrobial peptide cecropin A (CecA) can destroy planktonic and sessile biofilm-forming UPEC cells, either alone or when combined with the antibiotic nalidixic acid (NAL), synergistically clearing infection in vivo without off-target cytotoxicity. The multi-target mechanism of action involves outer membrane permeabilization followed by biofilm disruption triggered by the inhibition of efflux pump activity and interactions with extracellular and intracellular nucleic acids. These diverse targets ensure that resistance to the CecA + NAL combination emerges slowly. The antimicrobial mechanisms of CecA, thus, extend beyond pore-forming activity to include an unanticipated biofilm-eradication process, offering an alternative approach to combat antibiotic-resistant UPEC infections.
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17
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Charlton SGV, White MA, Jana S, Eland LE, Jayathilake PG, Burgess JG, Chen J, Wipat A, Curtis TP. Regulating, Measuring, and Modeling the Viscoelasticity of Bacterial Biofilms. J Bacteriol 2019; 201:e00101-19. [PMID: 31182499 PMCID: PMC6707926 DOI: 10.1128/jb.00101-19] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Biofilms occur in a broad range of environments under heterogeneous physicochemical conditions, such as in bioremediation plants, on surfaces of biomedical implants, and in the lungs of cystic fibrosis patients. In these scenarios, biofilms are subjected to shear forces, but the mechanical integrity of these aggregates often prevents their disruption or dispersal. Biofilms' physical robustness is the result of the multiple biopolymers secreted by constituent microbial cells which are also responsible for numerous biological functions. A better understanding of the role of these biopolymers and their response to dynamic forces is therefore crucial for understanding the interplay between biofilm structure and function. In this paper, we review experimental techniques in rheology, which help quantify the viscoelasticity of biofilms, and modeling approaches from soft matter physics that can assist our understanding of the rheological properties. We describe how these methods could be combined with synthetic biology approaches to control and investigate the effects of secreted polymers on the physical properties of biofilms. We argue that without an integrated approach of the three disciplines, the links between genetics, composition, and interaction of matrix biopolymers and the viscoelastic properties of biofilms will be much harder to uncover.
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Affiliation(s)
- Samuel G V Charlton
- School of Engineering, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Michael A White
- Interdisciplinary Computing & Complex BioSystems Research Group, School of Computing, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Saikat Jana
- School of Engineering, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Lucy E Eland
- Interdisciplinary Computing & Complex BioSystems Research Group, School of Computing, Newcastle University, Newcastle upon Tyne, United Kingdom
| | | | - J Grant Burgess
- School of Natural & Environmental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Jinju Chen
- School of Engineering, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Anil Wipat
- Interdisciplinary Computing & Complex BioSystems Research Group, School of Computing, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Thomas P Curtis
- School of Engineering, Newcastle University, Newcastle upon Tyne, United Kingdom
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18
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Prateeksha, Barik SK, Singh BN. Nanoemulsion-loaded hydrogel coatings for inhibition of bacterial virulence and biofilm formation on solid surfaces. Sci Rep 2019; 9:6520. [PMID: 31019240 PMCID: PMC6482171 DOI: 10.1038/s41598-019-43016-w] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 04/15/2019] [Indexed: 12/02/2022] Open
Abstract
The indiscriminate use of antibiotics has led to the emergence of drug-resistant bacteria which has become one of the biggest challenges of the twenty-first century for the researchers to combat and in turn search for novel targets which could lead to the development of effective and sustainable therapies. Inhibition of biofilm formation and virulence of bacterial pathogens is an emerging approach to address the challenges related to bacterial infections. To suppress the virulence and biofilm formation by Escherichia coli O157:H7 (ECOH), we developed stable nanoemulsion (NE) of Gaultheria fragrantissima Wall. essential oil’s (EO) bioactive compounds, viz., eugenol (E-NE) and methyl salicylate (MS-NE) that showed significantly higher anti-biofilm and anti-virulence activities as compared to eugenol and methyl salicylate without affecting ECOH planktonic cell growth. Transcriptional analysis showed that E-NE and MS-NE reduced the expression of genes, including curli, type I fimbriae, Shiga-like toxins, quorum sensing, and ler-controlled toxins, which are needed for biofilm formation, pathogenicity, and attachment. E-NE and MS-NE loaded hydrogel coatings showed superior anti-biofilm activity against ECOH on glass, plastic and meat surfaces as compared to eugenol and methyl salicylate loaded coatings. Conclusively, NE-loaded hydrogel coatings could be used in combating ECOH infection on solid surfaces through anti-biofilm and anti-virulence strategies.
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Affiliation(s)
- Prateeksha
- Herbal Nanobiotechnology Lab, Pharmacology Division, CSIR-National Botanical Research Institute, Lucknow, 226001, India
| | - Saroj Kanta Barik
- Herbal Nanobiotechnology Lab, Pharmacology Division, CSIR-National Botanical Research Institute, Lucknow, 226001, India.
| | - Brahma Nand Singh
- Herbal Nanobiotechnology Lab, Pharmacology Division, CSIR-National Botanical Research Institute, Lucknow, 226001, India.
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19
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Kwon HY, Kim JY, Liu X, Lee JY, Yam JKH, Dahl Hultqvist L, Xu W, Rybtke M, Tolker-Nielsen T, Heo W, Kim JJ, Kang NY, Joo T, Yang L, Park SJ, Givskov M, Chang YT. Visualizing biofilm by targeting eDNA with long wavelength probe CDr15. Biomater Sci 2019; 7:3594-3598. [DOI: 10.1039/c9bm00152b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We developed a small molecule CDr15, which has eDNA selectivity of bacterial biofilm.
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