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Infection and Immunity Feb 1977A levansucrase was demonstrated in the growth medium and in association with the cell surface of Actinomyces viscosus. The amount of enzyme produced relative to cell...
A levansucrase was demonstrated in the growth medium and in association with the cell surface of Actinomyces viscosus. The amount of enzyme produced relative to cell density is not significantly affected by the growth conditions. Sugar alcohols inhibit growth of the cells. The levansucrase hydrolyzes sucrose to produce free glucose and levan; some free fructose is also formed. There is no requirement for cofactors. The Km for sucrose is 12 mM. A variety of heavy metal ions and two disaccharides, lactose and cellobiose, inhibit the enzyme. The levansucrase was purified to homogeneity and has a specific activity of 90 micronmol of glucose release per min per mg. The enzyme has a molecular weight of 220,000 and is composed of subunits of molecular weight 80,000. The levan product contains both beta(2 leads to 1) and beta(2 leads to 6) linkages. The enzyme remains tightly bound to the levan product, resulting in the formation of high-molecular-weight polymer on the order of 10(8) daltons. The possible role of the levan and levansucrase of A. viscosus in the pathogenesis of periodontal disease is discussed.
Topics: Actinomyces; Concanavalin A; Disaccharides; Fructose; Glucose; Hexosyltransferases; Hydrogen-Ion Concentration; Kinetics; Metals; Molecular Conformation; Molecular Weight; Myeloma Proteins; Polysaccharides, Bacterial; Sucrose; Temperature; Tromethamine
PubMed: 14893
DOI: 10.1128/iai.15.2.518-526.1977 -
Annals of Medicine and Surgery (2012) Sep 2022The present study aims to study antibacterial effects and cellular mechanisms of iron oxide magnetic nanoparticles loaded with piroctone olamine (Fe3O4@PO NPs) against...
BACKGROUND
The present study aims to study antibacterial effects and cellular mechanisms of iron oxide magnetic nanoparticles loaded with piroctone olamine (Fe3O4@PO NPs) against some cariogenic bacteria ( and
METHODS
Nanoparticles was synthesized by the coprecipitation method. Antibacterial effects of Fe3O4@PO NPs were performed by calculating the minimum inhibitory concentration (MIC). We also evaluated the level of reactive oxygen species (ROS) and protein leakage to assess whether antibacterial effects may be dependent on these mechanisms.
RESULTS
The results demonstrated that PO showed the lowest antibacterial effect compared to other drugs tested with MICs values of 53.33 and 64 μg/ml for and , respectively. In contrast, the highest antibacterial effect was related to Fe3O4@PONPs with MICs values of 2.66 and 3.33 μg/ml for and , respectively. Fe3O4@PONPs, Fe3O4MNP, and PO markedly increased (p < 0.001) ROS production and protein leakage of tested bacteria at ≥¼ MIC, ≥1/3 MIC, and ½ MIC, respectively.
CONCLUSION
The findings of the present survey revealed the promising antibacterial effects of Fe3O4@PONP against some cariogenic bacteria; whereas it triggered the ROS production and protein leakage as the possible antibacterial mode of action of anti-infective agents. However, additional surveys are necessary to elucidate the accurate mechanisms of these nanoparticles.
PubMed: 36147164
DOI: 10.1016/j.amsu.2022.104291 -
Applied and Environmental Microbiology Sep 1987Lactobacillus casei ATCC 4646 and Actinomyces viscosus OMZ105E were found to differ markedly in acid tolerance. For example, pH profiles for glycolysis of intact cells...
Lactobacillus casei ATCC 4646 and Actinomyces viscosus OMZ105E were found to differ markedly in acid tolerance. For example, pH profiles for glycolysis of intact cells in dense suspensions indicated that glycolysis by L. casei had an optimal pH of about 6.0 and that glucose degradation was reduced by 50% at a pH of 4.2. Comparable values for A. viscosus cells were at pHs of about 7.0 and 5.6. The difference in acid tolerance appeared to depend mainly on membrane physiology, and the addition of 40 microM gramicidin to cell suspensions increased the sensitivity of the glycolytic system by as much as 1.5 pH units for L. casei and up to 0.5 pH unit for A. viscosus. L. casei cells were inherently somewhat more resistant to severe acid damage than were A. viscosus cells, in that Mg release from L. casei cells in medium with a pH of 3.0 occurred only after a lag of some 4 h, compared with rapid release from A. viscosus cells. However, the major differences pertinent to the physiology of the organisms appeared to be related to proton-translocating ATPases. Isolated membranes of L. casei had about 3.29 U of ATPase per mg of protein, compared with only about 0.06 U per mg of protein for those of A. viscosus. Moreover, the ATPase of L. casei had a pH optimum for hydrolytic activity of about 5, compared with an optimal pH of about 7 for that of A. viscosus.(ABSTRACT TRUNCATED AT 250 WORDS)
Topics: Actinomyces; Adenosine Triphosphatases; Cell Membrane; Cell Membrane Permeability; Fluorides; Glycolysis; Gramicidin; Humans; Hydrogen-Ion Concentration; Lacticaseibacillus casei; Magnesium; Protons
PubMed: 2445289
DOI: 10.1128/aem.53.9.2124-2128.1987 -
Infection and Immunity Sep 1979A total of 12 well-characterized strains of Actinomyces viscosus and A. naeslundii grown on Trypticase soy agar plates supplemented with sheep erythrocytes were examined... (Comparative Study)
Comparative Study
A total of 12 well-characterized strains of Actinomyces viscosus and A. naeslundii grown on Trypticase soy agar plates supplemented with sheep erythrocytes were examined by light microscopy and transmission electron microscopy after treatment with appropriately labeled antisera to homologous and heterologous strains. Cells incubated with homologous rabbit antisera followed by fluorescein-isothiocyanate (FITC)-conjugated goat anti-rabbit immunoglobulin G (IgG) exhibited a completely smooth fluorescent outline in the case of A. naeslundii and and interrupted, irregular fluorescent outline in the case of human strains of A. viscosus. The different labeling patterns appeared to be related to the presence at the ultrastructural level of long, unevenly distributed strands of "fuzz" on the surface of human A. viscosus cells, whereas A. naeslundii cells had a narrower layer of fuzz, or more even thickness. The immunocoating reaction revealed homologous antibody binding to the irregular strands of fuzz on the surface of human A. viscosus cells, whereas homologous antisera to A. naeslundii coated A. naeslundii cells with a moderately electron-dense coating of antibody of even thickness. Human strains of A. viscosus incubated with heterologous antiserum to A. naeslundii followed by FITC-labeled goat anti-rabbit IgG exhibited a segmented fluorescent outline, which differed from that produced with homologous antisera. A. naeslundii incubated with heterologous rabbit antisera to human A. viscosus strains and FITC-labeled anti-rabbit IgG exhibited a completely smooth fluorescent outline similar to that produced with homologous antiserum. A. viscosus strains of hamster origin differed from A. viscosus strains of human origin by the absence of a surface fuzz and the comparatively smooth, even fluorescence produced by incubating these cells with homologous rabbit antiserum followed by FITC-labeled goat anti-rabbit IgG. Antiserum to a hamster strain did not cross-react with A. naeslundii or human strains of A. viscosus. Under the growth conditions of this experiment, ultrastructural features and labeling patterns with the indirect fluorescent technique may be useful in differentiating these serotypes from one another.
Topics: Actinomyces; Antigens, Bacterial; Cell Membrane; Cell Wall; Fluorescent Antibody Technique; Microscopy, Electron; Species Specificity
PubMed: 387589
DOI: 10.1128/iai.25.3.1016-1028.1979 -
Microbes and Infection Sep 2012Actinomyces viscosus has been suggested to be associated with periodontal disease. However, the pathogenicity of this bacterium is not known. In this study, we examined...
Actinomyces viscosus has been suggested to be associated with periodontal disease. However, the pathogenicity of this bacterium is not known. In this study, we examined inflammation-inducing activity by A. viscosus. Whole cells and a lipophilic fraction of A. viscosus ATCC19246 induced production of interleukin-8 and tumor necrosis factor alpha from both human oral epithelial cells and human monocytoid cells. This cytokine production was blocked by lipoprotein lipase treatment of the lipophilic fraction. In addition, anti-Toll-like receptor 2 antibody blocked the cytokine production. These results suggest that lipoprotein of A. viscosus triggers inflammatory responses in periodontitis by activation of Toll-like receptor 2.
Topics: Actinomyces viscosus; Actinomycosis; Analysis of Variance; Bacterial Proteins; Cytokines; Epithelial Cells; Gingiva; Gingival Diseases; HEK293 Cells; Host-Pathogen Interactions; Humans; Inflammation; Lipoproteins; Macrophages; Toll-Like Receptor 2
PubMed: 22561467
DOI: 10.1016/j.micinf.2012.04.015 -
The Journal of Clinical Pediatric... 2003The first step in the origination of caries is the formation of a dental plaque. Dental caries can lead to destruction of enamel and dentin resulting in bacterial... (Review)
Review
The first step in the origination of caries is the formation of a dental plaque. Dental caries can lead to destruction of enamel and dentin resulting in bacterial invasion of the pulp. Invasion of the pulp and the periapical areas can promote the development of dento-alveolar abscess and spread of the infection to other anatomical areas. Several oral acid producing aerobic and anaerobic bacteria, including Streptococcus mutans, Lactobacillus acidophilus, and Actinomyces viscosus, are capable of initiating the carious lesion. The organisms that predominate in pulpitis and dento-alveolar abscess are Prevotella, Porphyromonas, Fusobacterium, and Peptostreptococcus spp. Treatment of caries involves removal of all affected tooth structure and proper replacement with a restorative material. Once pulpitis has developed the infected tissue should be removed and root canal therapy instituted, or the tooth should be extracted. Extraction, root canal therapy and/or drainage of pus usually are indicated for an abscess. Antimicrobial therapy supplementing the dental care should be considered, especially when local or systemic spread of the infection is suspected. Penicillin or amoxicillin are generally effective against most of the aerobic and anaerobic bacteria recovered. The patient whose oral cavity may harbor penicillin-resistant organisms should be considered for treatment with drugs effective against these organisms. These agents include amoxicillin-clavulanate, clindamycin or the combination of metronidazole plus amoxicillin or a macrolide.
Topics: Anti-Bacterial Agents; Bacteria, Anaerobic; Bacterial Infections; Child; Child, Preschool; Dental Caries; Drainage; Humans; Lactobacillus; Periapical Abscess; Pulpitis; Root Canal Therapy; Streptococcus mutans
PubMed: 14604136
DOI: 10.17796/jcpd.28.1.uwjxq61753506255 -
Infection and Immunity Feb 1980Laboratory strains representing six numerical taxonomy clusters and fresh isolates of human Actinomyces viscosus and Actinomyces naeslundii were studied by standard...
Laboratory strains representing six numerical taxonomy clusters and fresh isolates of human Actinomyces viscosus and Actinomyces naeslundii were studied by standard flocculation slide tests for the ability to hemagglutinate erythrocytes (RBC) from various animal species. Human AB and horse RBC were agglutinated more frequently and rapidly than others; guinea pig RBC were agglutinated by only a few strains. Human AB RBC were selected for studies of hemagglutination mechanisms. Treatment of RBC with clostridial neuraminidase (NTRBC) greatly enhanced hemagglutination for almost all strains. In hapten inhibition experiments in which various concentrations of sugars were used, beta-galactosides were the most effective inhibitors of hemagglutination for both RBC and NTRBC; inhibition of NTRBC agglutination required higher concentrations. Soybean lectin agglutinated both RBC and NTRBC but not Actinomyces cells. NTRBC agglutinated at a 125-fold-lower concentration. Hemagglutination was sensitive to ethylenediaminetetraacetate for one strain tested. Hemagglutination reactions were reversible by addition of beta-galactosides. The ability of Actinomyces strains to "prime" RBC for hemagglutination by removing sialic acid to expose more penultimate beta-galactoside sites was studied by recycling Actinomyces-agglutinated RBC which were dispersed with a lactose solution and washed free of bacteria (primed RBC). Priming in this manner augmented subsequent hemagglutination by indicator Actinomyces strains and made the RBC more sensitive to agglutination by soybean lectin. The priming ability of Actinomyces strains generally correlated with the amount of sialic acid removed from primed RBC. Strains representing the numerical taxonomy clusters differed in both their hemagglutinating and priming activities. Cluster 5 strains (typical A. naeslundii) were good agglutinators of RBC, NTRBC, and primed RBC but were poor primers. Cluster 3 strains (atypical A. naeslundii) were the weakest hemagglutinators but could prime RBC adequately for subsequent agglutination by other strains. Together, these data indicate that Actinomyces hemagglutination proceeds via a two-step mechanism: (i) neuraminidase removal of terminal sialic acid and (ii) lectin-like binding to exposed beta-galactoside-associated sites on the RBC. Strains differ in the extent to which they can perform the two functions, and this specificity may relate to their taxonomic classification.
Topics: Actinomyces; Animals; Carbohydrates; Edetic Acid; Galactosides; Guinea Pigs; Hemagglutination; Horses; Humans; Lectins; Neuraminidase
PubMed: 6769798
DOI: 10.1128/iai.27.2.335-343.1980 -
Journal of Clinical Microbiology Jun 1978Metronidazole (10 microgram/ml) and cadmium sulfate (20 microgram/ml) were added to a gelatin-based medium to select for microaerophilic Actinomyces species from dental... (Comparative Study)
Comparative Study
Metronidazole (10 microgram/ml) and cadmium sulfate (20 microgram/ml) were added to a gelatin-based medium to select for microaerophilic Actinomyces species from dental plaque samples. The new medium (GMC), when incubated anaerobically, allowed 98% recovery of seven pure cultures of Actinomyces viscosus and 73% recovery of eight pure cultures of Actinomyces naeslundii, while suppressing 76% of the total count of other organisms in dental plaque samples. In 203 plaque samples, recoveries of A. viscosus and A. naeslundii on GMC and another selective medium for oral Actinomyces (CNAC-20) were compared. Recovery of A. viscosus was comparable on the two media. Recovery of A. naeslundii was significantly higher on GMC than CNAC-20 (P is less than 0.001), and GMC allowed a more characteristic cell morphology of both organisms. GMC medium appears to be useful for the isolation and presumptive identification of A. viscosus and A. naeslundii from dental plaque.
Topics: Actinomyces; Cadmium; Culture Media; Dental Plaque; Humans; Kanamycin; Metronidazole
PubMed: 670376
DOI: 10.1128/jcm.7.6.514-518.1978 -
Frontiers in Microbiology 2022To investigate the degradation effect of bovine trypsin on multispecies biofilm of periodontitis-related bacteria and to provide an experimental reference for exploring...
To investigate the degradation effect of bovine trypsin on multispecies biofilm of periodontitis-related bacteria and to provide an experimental reference for exploring new methods for controlling biofilms of periodontitis-related microorganisms, the multispecies biofilm of periodontitis-related microorganisms was established. Standard strains of subsp. , , and were co-cultured to form the biofilm. The experimental groups were treated with bovine trypsin, distilled water was applied as the blank control group, and phosphate saline buffer (pH = 7.4) as the negative control group. Morphological observation and quantitative analysis of extracellular polymeric substances (EPS), live bacteria, and dead bacteria were conducted using a laser confocal microscope. The morphological changes of EPS and bacteria were also observed using a scanning electron microscope. The results of morphological observations of modeling were as follows. EPS aggregated as agglomerates, and bacteria flora were wrapped by them, showing a three-dimensional network structure, and channel-like structures were inside the biofilm. Live bacteria were distributed on the surface of the EPS or embedded in them, dead bacteria aggregated between live flora and the bottom layer of biofilms. After being treated with bovine trypsin, the three-dimensional network structure and the channel-like structure disappeared, and the EPS and live and dead bacteria decreased. Quantitative analysis results are as follows. When biofilm was treated for 30 s, 1 min, and 3 min, the minimum effective concentrations of bovine trypsin to reduce EPS were 2 mg/ml ( < 0.05), 0.5 mg/ml ( < 0.05), and 0.25 mg/ml ( < 0.05), respectively. The minimum effective concentrations of bovine trypsin to reduce the live or dead bacteria were 2 mg/ml ( < 0.05), 0.5 mg/ml ( < 0.05), and 0.5 mg/ml ( < 0.05), respectively. There was no significant difference in the ratio of live/dead bacteria after the biofilm was treated for 30 s with bovine trypsin at the concentration of 0.25, 0.5, 1, and 2 mg/ml ( > 0.05), and the minimum effective concentration to reduce the ratio of live bacteria/dead bacteria was 0.25 mg/ml ( < 0.05) after treatment for 1 min and 3 min. Therefore, bovine trypsin can destroy biofilm structure, disperse biofilm and bacteria flora, and reduce the EPS and bacterial biomass, which are positively correlated with the application time and concentration.
PubMed: 35992661
DOI: 10.3389/fmicb.2022.951291 -
Journal of Advanced Pharmaceutical... 2021This study is aimed to test the efficacy of C-10 Massoia lactone in oral polymicrobial degradation. Polymicrobial of , , , and were studied. C-10 Massoia lactone...
This study is aimed to test the efficacy of C-10 Massoia lactone in oral polymicrobial degradation. Polymicrobial of , , , and were studied. C-10 Massoia lactone against biofilm degradation was investigated using modified crystal violet for biofilm staining. The effectiveness of C-10 Massoia lactone against biofilms was calculated by the minimum biofilm inhibitory concentration (MBIC) and the minimum value of biofilm eradication concentration (MBEC). Scanning electron microscope was used to study biofilm cell viability and morphological changes. The results showed a degradation effect of C-10 Massoia lactone against mature oral polymicrobial at 0.25% v/v. C-10 Massoia lactone can degrade polymicrobial biofilms of , , and . This compound can destroy the extracellular polymeric substances (EPS) of polymicrobial biofilms. The potential application of C-10 Massoia lactone for anti-polymicrobial medication should be applied in such a way that any negative effects are minimized. Further research is needed to confirm the findings of this study.
PubMed: 33532362
DOI: 10.4103/japtr.JAPTR_105_20