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pH Landscapes in a Novel Five-Species Model of Early Dental Biofilm

BACKGROUND: Despite continued preventive efforts, dental caries remains the most common disease of man. Organic acids produced by microorganisms in dental plaque play a crucial role for the development of carious lesions. During early stages of the pathogenetic process, repeated pH drops induce chan...

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Autores principales: Schlafer, Sebastian, Raarup, Merete K., Meyer, Rikke L., Sutherland, Duncan S., Dige, Irene, Nyengaard, Jens R., Nyvad, Bente
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2011
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3179500/
https://www.ncbi.nlm.nih.gov/pubmed/21966490
http://dx.doi.org/10.1371/journal.pone.0025299
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author Schlafer, Sebastian
Raarup, Merete K.
Meyer, Rikke L.
Sutherland, Duncan S.
Dige, Irene
Nyengaard, Jens R.
Nyvad, Bente
author_facet Schlafer, Sebastian
Raarup, Merete K.
Meyer, Rikke L.
Sutherland, Duncan S.
Dige, Irene
Nyengaard, Jens R.
Nyvad, Bente
author_sort Schlafer, Sebastian
collection PubMed
description BACKGROUND: Despite continued preventive efforts, dental caries remains the most common disease of man. Organic acids produced by microorganisms in dental plaque play a crucial role for the development of carious lesions. During early stages of the pathogenetic process, repeated pH drops induce changes in microbial composition and favour the establishment of an increasingly acidogenic and aciduric microflora. The complex structure of dental biofilms, allowing for a multitude of different ecological environments in close proximity, remains largely unexplored. In this study, we designed a laboratory biofilm model that mimics the bacterial community present during early acidogenic stages of the caries process. We then performed a time-resolved microscopic analysis of the extracellular pH landscape at the interface between bacterial biofilm and underlying substrate. METHODOLOGY/PRINCIPAL FINDINGS: Strains of Streptococcus oralis, Streptococcus sanguinis, Streptococcus mitis, Streptococcus downei and Actinomyces naeslundii were employed in the model. Biofilms were grown in flow channels that allowed for direct microscopic analysis of the biofilms in situ. The architecture and composition of the biofilms were analysed using fluorescence in situ hybridization and confocal laser scanning microscopy. Both biofilm structure and composition were highly reproducible and showed similarity to in-vivo-grown dental plaque. We employed the pH-sensitive ratiometric probe C-SNARF-4 to perform real-time microscopic analyses of the biofilm pH in response to salivary solutions containing glucose. Anaerobic glycolysis in the model biofilms created a mildly acidic environment. Decrease in pH in different areas of the biofilms varied, and distinct extracellular pH-microenvironments were conserved over several hours. CONCLUSIONS/SIGNIFICANCE: The designed biofilm model represents a promising tool to determine the effect of potential therapeutic agents on biofilm growth, composition and extracellular pH. Ratiometric pH analysis using C-SNARF-4 gives detailed insight into the pH landscape of living biofilms and contributes to our general understanding of metabolic processes in in-vivo-grown bacterial biofilms.
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spelling pubmed-31795002011-09-30 pH Landscapes in a Novel Five-Species Model of Early Dental Biofilm Schlafer, Sebastian Raarup, Merete K. Meyer, Rikke L. Sutherland, Duncan S. Dige, Irene Nyengaard, Jens R. Nyvad, Bente PLoS One Research Article BACKGROUND: Despite continued preventive efforts, dental caries remains the most common disease of man. Organic acids produced by microorganisms in dental plaque play a crucial role for the development of carious lesions. During early stages of the pathogenetic process, repeated pH drops induce changes in microbial composition and favour the establishment of an increasingly acidogenic and aciduric microflora. The complex structure of dental biofilms, allowing for a multitude of different ecological environments in close proximity, remains largely unexplored. In this study, we designed a laboratory biofilm model that mimics the bacterial community present during early acidogenic stages of the caries process. We then performed a time-resolved microscopic analysis of the extracellular pH landscape at the interface between bacterial biofilm and underlying substrate. METHODOLOGY/PRINCIPAL FINDINGS: Strains of Streptococcus oralis, Streptococcus sanguinis, Streptococcus mitis, Streptococcus downei and Actinomyces naeslundii were employed in the model. Biofilms were grown in flow channels that allowed for direct microscopic analysis of the biofilms in situ. The architecture and composition of the biofilms were analysed using fluorescence in situ hybridization and confocal laser scanning microscopy. Both biofilm structure and composition were highly reproducible and showed similarity to in-vivo-grown dental plaque. We employed the pH-sensitive ratiometric probe C-SNARF-4 to perform real-time microscopic analyses of the biofilm pH in response to salivary solutions containing glucose. Anaerobic glycolysis in the model biofilms created a mildly acidic environment. Decrease in pH in different areas of the biofilms varied, and distinct extracellular pH-microenvironments were conserved over several hours. CONCLUSIONS/SIGNIFICANCE: The designed biofilm model represents a promising tool to determine the effect of potential therapeutic agents on biofilm growth, composition and extracellular pH. Ratiometric pH analysis using C-SNARF-4 gives detailed insight into the pH landscape of living biofilms and contributes to our general understanding of metabolic processes in in-vivo-grown bacterial biofilms. Public Library of Science 2011-09-23 /pmc/articles/PMC3179500/ /pubmed/21966490 http://dx.doi.org/10.1371/journal.pone.0025299 Text en Schlafer et al. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.
spellingShingle Research Article
Schlafer, Sebastian
Raarup, Merete K.
Meyer, Rikke L.
Sutherland, Duncan S.
Dige, Irene
Nyengaard, Jens R.
Nyvad, Bente
pH Landscapes in a Novel Five-Species Model of Early Dental Biofilm
title pH Landscapes in a Novel Five-Species Model of Early Dental Biofilm
title_full pH Landscapes in a Novel Five-Species Model of Early Dental Biofilm
title_fullStr pH Landscapes in a Novel Five-Species Model of Early Dental Biofilm
title_full_unstemmed pH Landscapes in a Novel Five-Species Model of Early Dental Biofilm
title_short pH Landscapes in a Novel Five-Species Model of Early Dental Biofilm
title_sort ph landscapes in a novel five-species model of early dental biofilm
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3179500/
https://www.ncbi.nlm.nih.gov/pubmed/21966490
http://dx.doi.org/10.1371/journal.pone.0025299
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