Project description:To combat dental implant-associated infections, there is a need for novel materials which effectively inhibit bacterial biofilm formation. In the present study, a titanium surface functionalization based on the “slippery liquid-infused porous surfaces” (SLIPS) principle was analyzed in an oral flow chamber system. The immobilized liquid layer was stable over 13 days of continuous flow. With increasing flow rates, the surface exhibited a significant reduction in attached biofilm of both the oral initial colonizer Streptococcus oralis and an oral multi-species biofilm composed of S. oralis, Actinomyces naeslundii, Veillonella dispar and Porphyromonas gingivalis. Using single cell force spectroscopy, reduced bacterial adhesion forces on the lubricant layer could be measured. Gene expression patterns in biofilms on SLIPS, on control surfaces and planktonic cultures were also compared. For this purpose, the genome of S. oralis strain ATCC® 9811TM was sequenced using PacBio Sequel technology. Even though biofilm cells showed clear changes in gene expression compared to planktonic cells, no differences could be detected between bacteria on SLIPS and on control surfaces. Therefore, it can be concluded that the ability of liquid-infused titanium to repel biofilms is solely due to weakened bacterial adhesion to the underlying liquid interface.
Project description:Oral biofilms, comprising hundreds of bacteria and other microorganisms on oral mucosal and dental surfaces, play a central role in oral health and disease dynamics. Streptococcus oralis, a key constituent of these biofilms, contribute significantly to their formation, serving as an early colonizer and microcolony scaffold. The interaction between S. oralis and the orally predominant mucin, MUC5B, is pivotal in biofilm development, yet the mechanism underlying MUC5B degradation remains poorly understood. This study introduces MdpS (Mucin Degrading Protease from Streptococcus oralis), a protease that extensively hydrolyses MUC5B and offers an insight into its sequence homology, physicochemical properties, and substrate- and amino acid specificity. MdpS exhibits high sequence conservation within the species and also explicitly among early biofilm colonizing streptococci. It is characterized as a calcium or magnesium dependent serine protease with strict physicochemical preferences, including narrow pH and temperature tolerance, and high sensitivity to increased sodium chloride and reducing agent concentrations. Furthermore, MdpS primarily hydrolyze proteins with O-glycans, but also show activity towards immunoglobulins IgA1/2 and IgM, suggesting potential immunomodulatory effects. Significantly, MdpS extensively degrades MUC5B in the N- and C-terminal domains, emphasizing its role in mucin degradation with implications in carbon and nitrogen sequestration for S. oralis with a potential function by cross-feeding the oral biofilm. Moreover, the enzyme displays amino acid preferences of serine, threonine or cysteine depending on substrate glycosylation. Understanding the interplay between S. oralis and MUC5B, facilitated by MdpS, has significant implications for the management of a healthy eubiotic oral microenvironment, offering potential targets for interventions aimed at modulating oral biofilm composition and succession. Additionally, the MdpS data challenges the presently acknowledged model of MUC5B degradation, because contrarily MdpS does not necessitate O-glycan removal prior to extensive peptide backbone hydrolysis. These findings emphasize the necessity for further research in this field.
Project description:Oral biofilms, comprising hundreds of bacteria and other microorganisms on oral mucosal and dental surfaces, play a central role in oral health and disease dynamics. Streptococcus oralis, a key constituent of these biofilms, contribute significantly to their formation, serving as an early colonizer and microcolony scaffold. The interaction between S. oralis and the orally predominant mucin, MUC5B, is pivotal in biofilm development, yet the mechanism underlying MUC5B degradation remains poorly understood. This study introduces MdpS (Mucin Degrading Protease from Streptococcus oralis), a protease that extensively hydrolyses MUC5B and offers an insight into its sequence homology, physicochemical properties, and substrate- and amino acid specificity. MdpS exhibits high sequence conservation within the species and also explicitly among early biofilm colonizing streptococci. It is characterized as a calcium or magnesium dependent serine protease with strict physicochemical preferences, including narrow pH and temperature tolerance, and high sensitivity to increased sodium chloride and reducing agent concentrations. Furthermore, MdpS primarily hydrolyze proteins with O-glycans, but also show activity towards immunoglobulins IgA1/2 and IgM, suggesting potential immunomodulatory effects. Significantly, MdpS extensively degrades MUC5B in the N- and C-terminal domains, emphasizing its role in mucin degradation with implications in carbon and nitrogen sequestration for S. oralis with a potential function by cross-feeding the oral biofilm. Moreover, the enzyme displays amino acid preferences of serine, threonine or cysteine depending on substrate glycosylation. Understanding the interplay between S. oralis and MUC5B, facilitated by MdpS, has significant implications for the management of a healthy eubiotic oral microenvironment, offering potential targets for interventions aimed at modulating oral biofilm composition and succession. Additionally, the MdpS data challenges the presently acknowledged model of MUC5B degradation, because contrarily MdpS does not necessitate O-glycan removal prior to extensive peptide backbone hydrolysis. These findings emphasize the necessity for further research in this field.
2024-04-18 | PXD046810 | Pride
Project description:In vitro biofilm growth of human oral biofilm
| PRJNA1021815 | ENA
Project description:Lectin staining of oral biofilm
| PRJNA833942 | ENA
Project description:Transcriptomic analysis of oral biofilm
Project description:<p>Bacterial metabolism in oral biofilms is comprised of complex networks of nutritional chains and biochemical regulations. These processes involve both intraspecies and interspecies networks as well as interactions with components from host saliva, gingival crevicular fluid, and dietary intake. In a previous paper, a large salivary glycoprotein, mucin MUC5B, was suggested to promote a dental health-related phenotype in the oral type strain of <em>Streptococcus gordonii</em> DL1, by regulating bacterial adhesion and protein expression. In this study, nuclear magnetic resonance-based metabolomics was used to examine the effects on the metabolic output of monospecies compared to dual species early biofilms of two clinical strains of oral commensal bacteria, <em>S. gordonii</em> and <em>Actinomyces naeslundii</em>, in the presence of MUC5B. The presence of <em>S. gordonii</em> increased colonization of <em>A. naeslundii</em> on salivary MUC5B, and both commensals were able to utilize MUC5B as a sole nutrient source during early biofilm formation. The metabolomes suggested that the bacteria were able to release mucin carbohydrates from oligosaccharide side chains as well as amino acids from the protein core. Synergistic effects were also seen in the dual species biofilm metabolome compared to the monospecies, indicating that <em>A. naeslundii</em> and <em>S. gordonii</em> cooperated in the degradation of salivary MUC5B. A better understanding of bacterial interactions and salivary-mediated regulation of early dental biofilm activity is meaningful for understanding oral biofilm physiology and may contribute to the development of future prevention strategies for biofilm-induced oral disease.</p>
Project description:Protein secretion into extracellular space is an important virulence mechanism both among Gram negative and Gram-positive bacteria. Prevotella intermedia, an important species associated with periodontitis, is known to be resistant to several antibiotics. Since P. intermedia is a part of normal oral microbiota, its complete elimination is not possible. Despite the remarkable clinical significance P. intermedia has, little is known about the molecular basis for its virulence. The aim of this study was to characterize the secretome of P. intermedia in biofilm and planktonic life mode. Proteins in the secretome preparations were identified by nanoLC-ESI-MS/MS. The biofilm secretome showed 109 proteins while the planktonic secretome showed 136 proteins. The biofilm and the planktonic secretomes contained 17 and 33 signal-peptide bearing proteins, 13 and 18 lipoproteins, respectively. Proteins with predicted virulence potential were 39 in biofilm and 44 in planktonic secretomes, respectively. Gene ontology analysis revealed that the biofilm secretome displayed a markedly higher percent proteins compared to planktonic secretome in terms of cellular amino acid metabolic process, nitrogen compound metabolic process, protein binding and methyltransferase and kinase activities. In conclusion, this study revealed differences in the protein profiles of P. intermedia biofilm and planktonic secretomes. This may set a basis for asking further questions into molecular mechanisms how this species exerts its virulence potential in the oral cavity.
2022-05-19 | PXD029419 | Pride
Project description:Strep. gordonii and Oral Biofilm Formation