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Doron Steinberg - One of the best experts on this subject based on the ideXlab platform.

  • The role of fructans on dental bio¢lm formation by Streptococcus sobrinus, Streptococcus mutans, Streptococcus gordonii
    2016
    Co-Authors: Actinomyces Viscosus, Ramona Rozen, Gilad Bachrach, Moshe Bronshteyn, I Gedalia, Doron Steinberg
    Abstract:

    Dental plaque biofilm plays a pivotal role in the progression of dental diseases. Polysaccharides are of great importance in the ecology of the dental biofilm. We studied the effect of fructans, glucans and a mixture of both fructans and glucans, synthesized in situ by immobilized fructosyltransferase or glucosyltransferase, on the adhesion of Streptococcus sobrinus, Streptococcus mutans, Streptococcus gordonii and Actinomyces viscosus to hydroxyapatite beads coated with human saliva (sHA). The adhesion of A. viscosus to sHA was found to be fructan-dependent. Adhesion of both S. sobrinus and S. mutans was found to be mediated mainly by glucans, while the adhesion of S. gordonii was found to be both glucan- and fructan-dependent. Treatment with fructanase prior to A. viscosus adhesion resulted in a significant reduction in adhesion to sHA, while adhesion of S. sobrinus, S. mutans and S. gordonii was slightly influenced by fructanase treatment. Treatment with fructanase after adhesion of S. gordonii to sHA resulted in a significant reduction in their adhesion to sHA. Our results show that fructans may play a role in the adhesion and colonization of several cariogenic bacteria to sHA, thus contributing to the formation of dental plaqu

  • initial biofilm formation of Streptococcus sobrinus on various orthodontics appliances
    Journal of Oral Rehabilitation, 2004
    Co-Authors: Doron Steinberg, Shahar Eyal
    Abstract:

    Biofilms accumulate on hard and soft surface in the oral cavity. Accumulation of biofilms on orthodontic appliance bear scientific and clinical interest. The objection of this study was to examine the formation of dental biofilm by Streptococcus sobrinus on different types of orthodontics appliances, using a model consisting of host and bacterial constituents. The adsorption pattern of saliva to the orthodontics appliances was determined by means of gel electrophoresis coupled with computerized densitometry techniques. The amount of salivary proteins adsorbed onto the surfaces was measured using the Bradford method. Sucrose-dependent bacterial adhesion to the saliva-coated orthodontics appliances was tested by radioactive-labelled S. sobrinus. Our results show different adsorption patterns of salivary proteins to the various orthodontic appliances as modules, brackets, springs and intra oral elastics. Modules and brackets demonstrated the most affinity to salivary proteins. A surface dependent adhesion profile was recorded, showing a high affinity of albumin and amylase to modules. Bacterial accumulation was the highest on modules compared with springs which demonstrated the least bacterial adhesion. Our study demonstrates the specificity of biofilm formation on the different orthodontic appliances. Formation of a variety of dental biofilms has a significant impact on the progression of dental diseases associated with orthodontic treatment.

  • Early formation of Streptococcus sobrinus biofilm on various dental restorative materials.
    Journal of dentistry, 2002
    Co-Authors: Doron Steinberg, Shahar Eyal
    Abstract:

    Abstract Objectives : To examine the formation of dental biofilm by Streptococcus sobrinus on different types of restorative materials, using a model consisting of host and bacterial constituents. Methods : The adsorption pattern of saliva to the restorative material was determined by means of gel electrophoresis coupled with computerized densitometry techniques. The amount of salivary proteins adsorbed onto the surfaces was measured using the Bradford method. Sucrose-dependent bacterial adhesion to the saliva-coated restorative material was tested by radioactive-labelled Streptococcus sobrinus, and viable counts of these bacteria in the biofilm was determined using bacterial culture techniques. Results : Different adsorption patterns by salivary proteins to restorative materials were recorded. Durafil and acrylic dental materials demonstrated the most affinity to salivary proteins. A surface dependent adhesion profile was recorded, showing a high affinity of albumin and amylase to Acrylic and Durafil materials. Bacterial accumulation was the highest with Fuji LC and Fuji GC, which also demonstrated the highest bacterial viability. Conclusions : Our study demonstrates the specificity of biofilm formation on different brands of dental restorative materials. Formation of a variety of dental biofilms has a significant impact on the progression of dental diseases in the oral cavity.

  • the role of fructans on dental biofilm formation by Streptococcus sobrinus Streptococcus mutans Streptococcus gordonii and actinomyces viscosus
    Fems Microbiology Letters, 2001
    Co-Authors: Ramona Rozen, Gilad Bachrach, Moshe Bronshteyn, I Gedalia, Doron Steinberg
    Abstract:

    Dental plaque biofilm plays a pivotal role in the progression of dental diseases. Polysaccharides are of great importance in the ecology of the dental biofilm. We studied the effect of fructans, glucans and a mixture of both fructans and glucans, synthesized in situ by immobilized fructosyltransferase or glucosyltransferase, on the adhesion of Streptococcus sobrinus, Streptococcus mutans, Streptococcus gordonii and Actinomyces viscosus to hydroxyapatite beads coated with human saliva (sHA). The adhesion of A. viscosus to sHA was found to be fructan-dependent. Adhesion of both S. sobrinus and S. mutans was found to be mediated mainly by glucans, while the adhesion of S. gordonii was found to be both glucan- and fructan-dependent. Treatment with fructanase prior to A. viscosus adhesion resulted in a significant reduction in adhesion to sHA, while adhesion of S. sobrinus, S. mutans and S. gordonii was slightly influenced by fructanase treatment. Treatment with fructanase after adhesion of S. gordonii to sHA resulted in a significant reduction in their adhesion to sHA. Our results show that fructans may play a role in the adhesion and colonization of several cariogenic bacteria to sHA, thus contributing to the formation of dental plaque biofilm.

  • growth rate and biofilm thickness of Streptococcus sobrinus and Streptococcus mutans on hydroxapatite
    Apmis, 2001
    Co-Authors: Ramona Rozen, Gilad Bachrach, Batia Zachs, Doron Steinberg
    Abstract:

    Bacteria in biofilm and planktonic bacteria exhibit different properties. The objective of the present study was to compare the growth rates of Streptococcus sobrinus and Streptococcus mutans on different types of biofilm with their planktonic growth rate. Our experimental model consisted of hydroxyapatite beads coated with human saliva (sHA). Glucans or fructans were synthesized in situ on sHA by immobilized cell-free glucosyltransferase or fructosyltransferase isolated from oral bacteria. S. sobrinus or S. mutans was then adsorbed onto the glucan- or fructan-coated sHA and incubated for different time intervals. The depth of the developing biofilm was measured. Our results show that growth rates of S. sobrinus and S. mutans on both fructan- and glucan-coated sHA were similar during a 23 h period. In addition, the profile was similar to the growth profile of the same planktonic bacteria. The resemblance in growth rates between planktonic and biofilm bacteria may be attributed to the thin and non-dense biofilm formed in the initial stages of the biofilm formation. The thin biofilm coat, reaching a maximal depth of 11 μm, has only imposed limited diffusion restrictions, thus not affecting the growth of the bacteria in the biofilm. Our study shows that growth of bacteria on surfaces may resemble their growth in suspension if the bacteria are not embedded in a thick dense biofilm.

R J Doyle - One of the best experts on this subject based on the ideXlab platform.

  • inhibitory effects of plant polyphenoloxidase on colonization factors of Streptococcus sobrinus 6715
    Antimicrobial Agents and Chemotherapy, 2000
    Co-Authors: M M Cowan, E A Horst, S Luengpailin, R J Doyle
    Abstract:

    Exogenously added polyphenoloxidase (EC 1.14.18.1), an enzyme which oxidizes tyrosine residues and is commonly found in many dietary components, abolished the aggregation of Streptococcus sobrinus 6715 by high-molecular-weight dextran. The enzyme decreased glucan-binding lectin and/or glucosyltransferase I activities.

  • multiple glucan binding proteins of Streptococcus sobrinus
    Journal of Bacteriology, 1996
    Co-Authors: M O Lassiter, K. G. Taylor, J A Banas, Michael Y Galperin, R J Doyle
    Abstract:

    Several proteins from culture supernatants of Streptococcus sobrinus were able to bind avidly to Sephadex G-75. The proteins could be partially eluted from the Sephadex by low-molecular-weight alpha-1,6 glucan or fully eluted by 4 M guanidine hydrochloride. Elution profiles were complex, yielding proteins of 16, 45, 58 to 60, 90, 135, and 145 kDa, showing that the wild-type strain possessed multiple glucan-binding proteins. Two mutants of Streptococcus sobrinus incapable of aggregation by high-molecular-weight alpha-1,6 glucan were isolated. One mutant was spontaneous, from a cell suspension to which glucan had been added, whereas the other was induced by ethyl methanesulfonate. Both mutants were devoid of a 60-kDa protein, as shown by gel electrophoresis of culture supernatants and whole cells. Amino acid analysis showed that the 58- to 60-kDa protein and the 90-kDa protein were distinct, although both were N-terminally blocked. Both mutants retained their ability to adhere to glass in the presence of sucrose and to ferment mannitol and sorbitol. Both mutants retained their glucosytransferase activities, as shown by activity gels. Western blots (immunoblots), employing antibody against a glucan-binding protein of Streptococcus mutans, failed to reveal cross-reactivity with S. sobrinus proteins. The results show that even though S. sobrinus produces several proteins capable of binding alpha-1,6 glucans, the 60-kDa protein is probably the lectin needed for glucan-dependent cellular aggregation.

  • Subinhibitory concentrations of antibiotics affect cell surface properties of Streptococcus sobrinus
    Journal of Bacteriology, 1995
    Co-Authors: Qi Wu, K. G. Taylor, Q Wang, R J Doyle
    Abstract:

    Several antibiotics, at subinhibitory concentrations, caused an increase in the ability of Streptococcus sobrinus to bind alpha-1,6-glucans, whereas other antibiotics decreased glucan binding. In every case, glucan binding was inversely proportional to cell surface hydrophobicity. High levels of glucan-binding activity resulted in low levels of hydrophobicity, whereas low levels of glucan binding caused high levels of cellular hydrophobicity. The results show that low concentrations of antibiotics may modulate lectin and hydrophobin adhesins in streptococci.

Ramona Rozen - One of the best experts on this subject based on the ideXlab platform.

  • The role of fructans on dental bio¢lm formation by Streptococcus sobrinus, Streptococcus mutans, Streptococcus gordonii
    2016
    Co-Authors: Actinomyces Viscosus, Ramona Rozen, Gilad Bachrach, Moshe Bronshteyn, I Gedalia, Doron Steinberg
    Abstract:

    Dental plaque biofilm plays a pivotal role in the progression of dental diseases. Polysaccharides are of great importance in the ecology of the dental biofilm. We studied the effect of fructans, glucans and a mixture of both fructans and glucans, synthesized in situ by immobilized fructosyltransferase or glucosyltransferase, on the adhesion of Streptococcus sobrinus, Streptococcus mutans, Streptococcus gordonii and Actinomyces viscosus to hydroxyapatite beads coated with human saliva (sHA). The adhesion of A. viscosus to sHA was found to be fructan-dependent. Adhesion of both S. sobrinus and S. mutans was found to be mediated mainly by glucans, while the adhesion of S. gordonii was found to be both glucan- and fructan-dependent. Treatment with fructanase prior to A. viscosus adhesion resulted in a significant reduction in adhesion to sHA, while adhesion of S. sobrinus, S. mutans and S. gordonii was slightly influenced by fructanase treatment. Treatment with fructanase after adhesion of S. gordonii to sHA resulted in a significant reduction in their adhesion to sHA. Our results show that fructans may play a role in the adhesion and colonization of several cariogenic bacteria to sHA, thus contributing to the formation of dental plaqu

  • the role of fructans on dental biofilm formation by Streptococcus sobrinus Streptococcus mutans Streptococcus gordonii and actinomyces viscosus
    Fems Microbiology Letters, 2001
    Co-Authors: Ramona Rozen, Gilad Bachrach, Moshe Bronshteyn, I Gedalia, Doron Steinberg
    Abstract:

    Dental plaque biofilm plays a pivotal role in the progression of dental diseases. Polysaccharides are of great importance in the ecology of the dental biofilm. We studied the effect of fructans, glucans and a mixture of both fructans and glucans, synthesized in situ by immobilized fructosyltransferase or glucosyltransferase, on the adhesion of Streptococcus sobrinus, Streptococcus mutans, Streptococcus gordonii and Actinomyces viscosus to hydroxyapatite beads coated with human saliva (sHA). The adhesion of A. viscosus to sHA was found to be fructan-dependent. Adhesion of both S. sobrinus and S. mutans was found to be mediated mainly by glucans, while the adhesion of S. gordonii was found to be both glucan- and fructan-dependent. Treatment with fructanase prior to A. viscosus adhesion resulted in a significant reduction in adhesion to sHA, while adhesion of S. sobrinus, S. mutans and S. gordonii was slightly influenced by fructanase treatment. Treatment with fructanase after adhesion of S. gordonii to sHA resulted in a significant reduction in their adhesion to sHA. Our results show that fructans may play a role in the adhesion and colonization of several cariogenic bacteria to sHA, thus contributing to the formation of dental plaque biofilm.

  • growth rate and biofilm thickness of Streptococcus sobrinus and Streptococcus mutans on hydroxapatite
    Apmis, 2001
    Co-Authors: Ramona Rozen, Gilad Bachrach, Batia Zachs, Doron Steinberg
    Abstract:

    Bacteria in biofilm and planktonic bacteria exhibit different properties. The objective of the present study was to compare the growth rates of Streptococcus sobrinus and Streptococcus mutans on different types of biofilm with their planktonic growth rate. Our experimental model consisted of hydroxyapatite beads coated with human saliva (sHA). Glucans or fructans were synthesized in situ on sHA by immobilized cell-free glucosyltransferase or fructosyltransferase isolated from oral bacteria. S. sobrinus or S. mutans was then adsorbed onto the glucan- or fructan-coated sHA and incubated for different time intervals. The depth of the developing biofilm was measured. Our results show that growth rates of S. sobrinus and S. mutans on both fructan- and glucan-coated sHA were similar during a 23 h period. In addition, the profile was similar to the growth profile of the same planktonic bacteria. The resemblance in growth rates between planktonic and biofilm bacteria may be attributed to the thin and non-dense biofilm formed in the initial stages of the biofilm formation. The thin biofilm coat, reaching a maximal depth of 11 μm, has only imposed limited diffusion restrictions, thus not affecting the growth of the bacteria in the biofilm. Our study shows that growth of bacteria on surfaces may resemble their growth in suspension if the bacteria are not embedded in a thick dense biofilm.

Toshihiko Koga - One of the best experts on this subject based on the ideXlab platform.

  • development of a 5 nuclease based real time pcr assay for quantitative detection of cariogenic dental pathogens Streptococcus mutans and Streptococcus sobrinus
    Journal of Clinical Microbiology, 2003
    Co-Authors: Akihiro Yoshida, Nao Suzuki, Yoshio Nakano, Miki Kawada, Takahiko Oho, Toshihiko Koga
    Abstract:

    A 5' nuclease TaqMan PCR assay was developed for the quantitative detection of the major cariogenic bacteria Streptococcus mutans and Streptococcus sobrinus. The absolute and relative numbers of bacteria were measured by this method. This assay will be useful for quantifying these organisms in oral specimens and for analyzing biofilm formation.

  • simple and rapid detection of Streptococcus mutans and Streptococcus sobrinus in human saliva by polymerase chain reaction
    Oral Microbiology and Immunology, 2000
    Co-Authors: Yoshihisa Yamashita, Yoshihiro Shimazaki, Mitoshi Kushiyama, Toshihiko Koga
    Abstract:

    Streptococcus mutans and Streptococcus sobrinus are major pathogens causing dental caries in humans. A simple and rapid method to detect these species in human saliva simultaneously was developed using the polymerase chain reaction (PCR). Chromosomal DNA was extracted by boiling bacterial cells in lysis solution containing 1% Triton X-100. Oligonucleotide primers specific for portions of the glucosyltransferase genes (gtfB of S. mutans and gtf1 of S. sobrinus) were designed. After PCR using two sets of these primers, S. mutans and S. sobrinus were specifically identified. The method was capable of amplifying DNA fragments specific for these species from chromosomal DNA extracted from 1×10 3 cells, or from 10 μl of clinical saliva samples containing 1×10 colony-forming units of either streptococcal species. A second PCR, using the first PCR product as a template with newly designed internal primers, made it possible to detect 1×10 2 colony-forming units of either streptococcal species in 10 μl of saliva samples. These results indicate that the PCR method developed in this study is useful for detecting S. mutans and S. sobrinus in saliva and that it can be used in epidemiological studies to evaluate the prevalence level of these organisms.

  • simple and rapid detection of Streptococcus mutans and Streptococcus sobrinus in human saliva by polymerase chain reaction
    Oral Microbiology and Immunology, 2000
    Co-Authors: Takahiko Oho, Yoshihisa Yamashita, Yoshihiro Shimazaki, Mitoshi Kushiyama, Toshihiko Koga
    Abstract:

    Streptococcus mutans and Streptococcus sobrinus are major pathogens causing dental caries in humans. A simple and rapid method to detect these species in human saliva simultaneously was developed using the polymerase chain reaction (PCR). Chromosomal DNA was extracted by boiling bacterial cells in lysis solution containing 1% Triton X-100. Oligonucleotide primers specific for portions of the glucosyltransferase genes (gtfB of S. mutans and gtfI of S. sobrinus) were designed. After PCR using two sets of these primers, S. mutans and S. sobrinus were specifically identified. The method was capable of amplifying DNA fragments specific for these species from chromosomal DNA extracted from 1 x 10(3) cells, or from 10 microliters of clinical saliva samples containing 1 x 10(3) colony-forming units of either streptococcal species. A second PCR, using the first PCR product as a template with newly designed internal primers, made it possible to detect 1 x 10(2) colony-forming units of either streptococcal species in 10 microliters of saliva samples. These results indicate that the PCR method developed in this study is useful for detecting S. mutans and S. sobrinus in saliva and that it can be used in epidemiological studies to evaluate the prevalence level of these organisms.

Gilad Bachrach - One of the best experts on this subject based on the ideXlab platform.

  • The role of fructans on dental bio¢lm formation by Streptococcus sobrinus, Streptococcus mutans, Streptococcus gordonii
    2016
    Co-Authors: Actinomyces Viscosus, Ramona Rozen, Gilad Bachrach, Moshe Bronshteyn, I Gedalia, Doron Steinberg
    Abstract:

    Dental plaque biofilm plays a pivotal role in the progression of dental diseases. Polysaccharides are of great importance in the ecology of the dental biofilm. We studied the effect of fructans, glucans and a mixture of both fructans and glucans, synthesized in situ by immobilized fructosyltransferase or glucosyltransferase, on the adhesion of Streptococcus sobrinus, Streptococcus mutans, Streptococcus gordonii and Actinomyces viscosus to hydroxyapatite beads coated with human saliva (sHA). The adhesion of A. viscosus to sHA was found to be fructan-dependent. Adhesion of both S. sobrinus and S. mutans was found to be mediated mainly by glucans, while the adhesion of S. gordonii was found to be both glucan- and fructan-dependent. Treatment with fructanase prior to A. viscosus adhesion resulted in a significant reduction in adhesion to sHA, while adhesion of S. sobrinus, S. mutans and S. gordonii was slightly influenced by fructanase treatment. Treatment with fructanase after adhesion of S. gordonii to sHA resulted in a significant reduction in their adhesion to sHA. Our results show that fructans may play a role in the adhesion and colonization of several cariogenic bacteria to sHA, thus contributing to the formation of dental plaqu

  • the role of fructans on dental biofilm formation by Streptococcus sobrinus Streptococcus mutans Streptococcus gordonii and actinomyces viscosus
    Fems Microbiology Letters, 2001
    Co-Authors: Ramona Rozen, Gilad Bachrach, Moshe Bronshteyn, I Gedalia, Doron Steinberg
    Abstract:

    Dental plaque biofilm plays a pivotal role in the progression of dental diseases. Polysaccharides are of great importance in the ecology of the dental biofilm. We studied the effect of fructans, glucans and a mixture of both fructans and glucans, synthesized in situ by immobilized fructosyltransferase or glucosyltransferase, on the adhesion of Streptococcus sobrinus, Streptococcus mutans, Streptococcus gordonii and Actinomyces viscosus to hydroxyapatite beads coated with human saliva (sHA). The adhesion of A. viscosus to sHA was found to be fructan-dependent. Adhesion of both S. sobrinus and S. mutans was found to be mediated mainly by glucans, while the adhesion of S. gordonii was found to be both glucan- and fructan-dependent. Treatment with fructanase prior to A. viscosus adhesion resulted in a significant reduction in adhesion to sHA, while adhesion of S. sobrinus, S. mutans and S. gordonii was slightly influenced by fructanase treatment. Treatment with fructanase after adhesion of S. gordonii to sHA resulted in a significant reduction in their adhesion to sHA. Our results show that fructans may play a role in the adhesion and colonization of several cariogenic bacteria to sHA, thus contributing to the formation of dental plaque biofilm.

  • growth rate and biofilm thickness of Streptococcus sobrinus and Streptococcus mutans on hydroxapatite
    Apmis, 2001
    Co-Authors: Ramona Rozen, Gilad Bachrach, Batia Zachs, Doron Steinberg
    Abstract:

    Bacteria in biofilm and planktonic bacteria exhibit different properties. The objective of the present study was to compare the growth rates of Streptococcus sobrinus and Streptococcus mutans on different types of biofilm with their planktonic growth rate. Our experimental model consisted of hydroxyapatite beads coated with human saliva (sHA). Glucans or fructans were synthesized in situ on sHA by immobilized cell-free glucosyltransferase or fructosyltransferase isolated from oral bacteria. S. sobrinus or S. mutans was then adsorbed onto the glucan- or fructan-coated sHA and incubated for different time intervals. The depth of the developing biofilm was measured. Our results show that growth rates of S. sobrinus and S. mutans on both fructan- and glucan-coated sHA were similar during a 23 h period. In addition, the profile was similar to the growth profile of the same planktonic bacteria. The resemblance in growth rates between planktonic and biofilm bacteria may be attributed to the thin and non-dense biofilm formed in the initial stages of the biofilm formation. The thin biofilm coat, reaching a maximal depth of 11 μm, has only imposed limited diffusion restrictions, thus not affecting the growth of the bacteria in the biofilm. Our study shows that growth of bacteria on surfaces may resemble their growth in suspension if the bacteria are not embedded in a thick dense biofilm.