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FEMS Microbiology Letters Nov 2008Actinomyces spp., predominant members of human oral biofilms, may use extracellular sialidase to promote adhesion, deglycosylate immunoglobulins and liberation of...
Actinomyces spp., predominant members of human oral biofilms, may use extracellular sialidase to promote adhesion, deglycosylate immunoglobulins and liberation of nutrients. Partial nanH gene sequences (1,077 bp) from Actinomyces oris (n=74), Actinomyces naeslundii (n=30), Actinomyces viscosus (n=1) and Actinomyces johnsonii (n=2) which included the active-site region and the bacterial neuraminidase repeats (BNRs) were compared. The sequences were aligned and each species formed a distinct cluster with five isolates having intermediate positions. These five isolates (two A. oris and three A. naeslundii) exhibited interspecies recombination. The nonsynonymous/synonymous ratio was <1 for both A. oris and A. naeslundii indicating that nanH in both species is under stabilizing selective pressure; nonsynonymous mutations are not selected. However, for A. oris significant negative values in tests for neutral selection suggested the rate of mutation in A. oris was greater than in A. naeslundii but with selection against nonsynonymous mutations. This was supported by the observation that the frequency of polymorphic sites in A. oris, which were monomorphic in A. naeslundii was significantly greater than the frequency of polymorphic sites in A. naeslundii which were monomorphic in A. oris (chi(2)=7.011; P=0.00081). The higher proportions of A. oris in the oral biofilm might be explained by the higher mutation rate facilitating an increased ability to respond successfully to environmental stress.
Topics: Actinomyces; Actinomycosis; Bacterial Proteins; Dental Plaque; Humans; Molecular Sequence Data; Mouth; Neuraminidase; Recombination, Genetic; Sequence Analysis, DNA; Species Specificity
PubMed: 18823396
DOI: 10.1111/j.1574-6968.2008.01336.x -
Journal of Bacteriology Nov 1967This study was an attempt to develop a fluorescent-antibody (FA) test to differentiate Actinomyces israelii and A. naeslundii as an aid in their laboratory... (Comparative Study)
Comparative Study
This study was an attempt to develop a fluorescent-antibody (FA) test to differentiate Actinomyces israelii and A. naeslundii as an aid in their laboratory identification. Two strains of A. israelii (X522 and A601) and two strains of A. naeslundii (X454 and X600), which had received intensive study by several investigators, were used for the immunization of rabbits. Working titers, based on tests with antigens prepared from the homologous strains and from well-established heterologous strains, were determined for each labeled antibody preparation. These conjugates and their normal serum control conjugates were used separately to stain 85 cultures of Actinomyes species and 23 strains of other species that might be confused with them. Acetone-precipitated soluble antigens from these same strains were tested with different antisera in the agar-gel diffusion test. Results showed that A. israelii (X522 and A601) and A. naeslundii (X454 and X600) labeled antiglobulins, when used at their working titers, stained most strains of their homologous species. Agar-gel diffusion results showed general agreement with those of the FA tests. The two tests appear to be equal in sensitivity, but the FA test is more specific, since several cross-reactions were noted with the agar-gel diffusion test whereas no cross-reactions were obtained with the FA reagents. Agar-gel and FA studies suggest that at least two serotypes of A. israelii may be associated with human disease. Although the majority of strains tested in this study appear to belong to a common serotype, "serotype 1," two strains of an apparent second serotype, "serotype 2," were encountered. FA staining of tissue impression smears from experimentally infected mice was successful when a counterstain, Evans Blue dye, was used.
Topics: Actinomyces; Actinomycosis; Animals; Antigen-Antibody Reactions; Antigens; Clinical Laboratory Techniques; Diagnosis, Differential; Fluorescent Antibody Technique; Humans; Immune Sera; Immunodiffusion; Mice; Rabbits
PubMed: 4964473
DOI: 10.1128/jb.94.5.1287-1295.1967 -
BMC Oral Health Apr 2021The aim of this study was to determine in vitro the bactericidal potential of 38% silver diamine fluoride (SDF) alone, potassium iodide (PI) alone, and the two in...
BACKGROUND
The aim of this study was to determine in vitro the bactericidal potential of 38% silver diamine fluoride (SDF) alone, potassium iodide (PI) alone, and the two in combination (SDF + PI) against three bacterial species commonly found in root canal samples (Enterococcus faecalis, Actinomyces naeslundii and Parvimonas micra).
METHODS
The potential bactericidal rates for SDF, PI and SDF + PI against E. faecalis, A. naeslundii and P. micra were calculated as reduction of bacteria colony forming units.
RESULTS
The bactericidal potential of SDF was at 99.97-100% against E. faecalis and 100% against A. naeslundii and P. micra. SDF + PI showed a 100% bactericidal effect against P. micra, 99.89-99.98% against E. faecalis and 99.98-100% against A. naeslundii. The bactericidal effect of PI was 99.51-99.98% against E. faecalis, 99.27-99.95% against A. naeslundii and 99.93-100% against P. micra. The differences between controls and bacteria exposed to the antibacterial agents were statistically significant (p < 0.05).
CONCLUSIONS
SDF had an effective bactericidal effect against the examined bacteria. However, the limitations of this in vitro study do not allow a recommendation of the employment of these solutions as root canal irrigants. Additional investigations are necessary to assess their endodontic clinical applicability.
Topics: Actinomyces; Anti-Bacterial Agents; Enterococcus faecalis; Firmicutes; Fluorides, Topical; Humans; Potassium Iodide; Quaternary Ammonium Compounds; Root Canal Irrigants; Silver Compounds
PubMed: 33827520
DOI: 10.1186/s12903-021-01531-1 -
Infection and Immunity May 1999Oral strains of Actinomyces spp. express type 1 fimbriae, which are composed of major FimP subunits, and bind preferentially to salivary acidic proline-rich proteins... (Comparative Study)
Comparative Study
Strains of Actinomyces naeslundii and Actinomyces viscosus exhibit structurally variant fimbrial subunit proteins and bind to different peptide motifs in salivary proteins.
Oral strains of Actinomyces spp. express type 1 fimbriae, which are composed of major FimP subunits, and bind preferentially to salivary acidic proline-rich proteins (APRPs) or to statherin. We have mapped genetic differences in the fimP subunit genes and the peptide recognition motifs within the host proteins associated with these differential binding specificities. The fimP genes were amplified by PCR from Actinomyces viscosus ATCC 19246, with preferential binding to statherin, and from Actinomyces naeslundii LY7, P-1-K, and B-1-K, with preferential binding to APRPs. The fimP gene from the statherin-binding strain 19246 is novel and has about 80% nucleotide and amino acid sequence identity to the highly conserved fimP genes of the APRP-binding strains (about 98 to 99% sequence identity). The novel FimP protein contains an amino-terminal signal peptide, randomly distributed single-amino-acid substitutions, and structurally different segments and ends with a cell wall-anchoring and a membrane-spanning region. When agarose beads with CNBr-linked host determinant-specific decapeptides were used, A. viscosus 19246 bound to the Thr42Phe43 terminus of statherin and A. naeslundii LY7 bound to the Pro149Gln150 termini of APRPs. Furthermore, while the APRP-binding A. naeslundii strains originate from the human mouth, A. viscosus strains isolated from the oral cavity of rat and hamster hosts showed preferential binding to statherin and contained the novel fimP gene. Thus, A. viscosus and A. naeslundii display structurally variant fimP genes whose protein products are likely to interact with different peptide motifs and to determine animal host tropism.
Topics: Actinomyces; Amino Acid Sequence; Animals; Bacterial Proteins; Base Sequence; Binding Sites; Cricetinae; DNA Primers; Fimbriae, Bacterial; Genes, Bacterial; Humans; Molecular Sequence Data; Mouth; Protein Binding; Rats; Salivary Proteins and Peptides; Sequence Homology, Amino Acid; Species Specificity
PubMed: 10225854
DOI: 10.1128/IAI.67.5.2053-2059.1999 -
Infection and Immunity Sep 1998Actinomyces naeslundii genospecies 1 and 2 bind to acidic proline-rich proteins (APRPs) and statherin via type 1 fimbriae and to beta-linked galactosamine (GalNAcbeta)...
Actinomyces naeslundii displays variant fimP and fimA fimbrial subunit genes corresponding to different types of acidic proline-rich protein and beta-linked galactosamine binding specificity.
Actinomyces naeslundii genospecies 1 and 2 bind to acidic proline-rich proteins (APRPs) and statherin via type 1 fimbriae and to beta-linked galactosamine (GalNAcbeta) structures via type 2 fimbriae. In addition, A. naeslundii displays two types of binding specificity for both APRPs-statherin and GalNAcbeta, while Actinomyces odontolyticus binds to unknown structures. To study the molecular basis for these binding specificities, DNA fragments spanning the entire or central portions of fimP (type 1) and fimA (type 2) fimbrial subunit genes were amplified by PCR from strains of genospecies 1 and 2 and hybridized with DNA from two independent collections of oral Actinomyces isolates. Isolates of genospecies 1 and 2 and A. odontolyticus, but no other Actinomyces species, were positive for hybridization with fimP and fimA full-length probes irrespective of binding to APRPs and statherin, GalNAcbeta, or unknown structures. Isolates of genospecies 1 and 2, with deviating patterns of GalNAcbeta1-3Galalpha-O-ethyl-inhibitable coaggregation with Streptococcus oralis Ss34 and MPB1, were distinguished by a fimA central probe from genospecies 1 and 2, respectively. Furthermore, isolates of genospecies 1 and 2 displaying preferential binding to APRPs over statherin were positive with a fimP central probe, while a genospecies 2 strain with the opposite binding preference was not. The sequences of fimP and fimA central gene segments were highly conserved among isolates with the same, but diversified between those with a variant, binding specificity. In conclusion, A. naeslundii exhibits variant fimP and fimA genes corresponding to diverse APRP and GalNAcbeta specificities, respectively, while A. odontolyticus has a genetically related but distinct adhesin binding specificity.
Topics: Actinomyces; Adhesins, Bacterial; Amino Acid Sequence; Bacterial Proteins; Fimbriae Proteins; Fimbriae, Bacterial; Galactosamine; Genes, Bacterial; Genetic Variation; Molecular Sequence Data; Peptides; Proline; Proline-Rich Protein Domains
PubMed: 9712794
DOI: 10.1128/IAI.66.9.4403-4410.1998 -
BMC Oral Health May 2019Zinc oxide nanoparticles (ZnONPs) have been widely studied as bactericidal reagents. However, it is still challenging to use ZnONPs as a root canal sealant to eliminate...
BACKGROUND
Zinc oxide nanoparticles (ZnONPs) have been widely studied as bactericidal reagents. However, it is still challenging to use ZnONPs as a root canal sealant to eliminate infecting microorganisms in the root canal system. This study aimed at understanding the antibacterial and biofilm effects of ZnONPs in the infected root canal and their effect on cell function.
METHODS
This study aimed to develop a better understanding of the antibacterial effects of ZnONPs in the infected root canal and their effect on cell function. Experiments were performed in two stages; the first stage included inhibition zone tests and the minimum inhibitory concentration (MIC) test, which were performed to examine the antibacterial activity of ZnONPs against Porphyromonas gingivalis (P. gingivalis) and Actinomyces Naeslundii (A. naeslundii) bacteria in vitro. ZnONPs were further evaluated for their biocompatibility using normal mouse NIH3T3 and OCCM-30 cells by the cell-based MTT assay. In addition, the influence of ZnONPs on matrix metalloproteinases in NIH3T3 cells and their inhibiting factors (Mmp13 and Timp1) were measured using the real-time PCR technique and western blot method.
RESULTS
The MIC of ZnONPs against P. gingivalis and A. naeslundii were confirmed to be 10 μg/mL and 40 μg/mL, respectively. The MTT assay showed that ZnONPs were nontoxic. The RT-PCR and western blotting results showed that Mmp13 was downregulated and Timp1 expression was increased. Meanwhile, ZnONPs were shown to increase the expression of the OCCM-30 osteogenesis-related factors Bsp and Runx2. Finally, there was no significant change in the morphology of NIH3T3 and OCCM-30 cells after the addition of different concentrations of ZnONPs for different periods of time.
CONCLUSION
ZnONPs have excellent antibacterial activity against P. gingivalis and A. naeslundii and have low cell cytotoxicity in vitro.
Topics: Actinomyces; Animals; Anti-Bacterial Agents; Dental Cementum; Mice; NIH 3T3 Cells; Nanoparticles; Porphyromonas gingivalis; Zinc Oxide
PubMed: 31088450
DOI: 10.1186/s12903-019-0780-y -
Journal of Dental Research Jan 2020Periodontitis is positively linked to cardiovascular disease (CVD), diabetes, cancer, and increased mortality. Empirically derived clusters of IgG antibodies against 19...
Periodontitis is positively linked to cardiovascular disease (CVD), diabetes, cancer, and increased mortality. Empirically derived clusters of IgG antibodies against 19 selected periodontal microorganisms have been associated with hyperglycemia. We further investigated associations between these serum IgG antibody clusters and all-cause and CVD mortality in a representative US population. Participants free of CVD and cancer and aged ≥40 y at baseline ( = 6,491) from the Third National Health and Nutrition Examination Survey (1988 to 1994) were followed up until December 31, 2011. Antibodies were categorized into 4 clusters: red-green, orange-red, yellow-orange, and orange-blue. Over a 23-y follow-up, 2,702 deaths occurred, including 810 CVD-related deaths. In fully adjusted Cox proportional hazard models, the red-green cluster was positively associated with all-cause mortality (tertile 3 vs. tertile 1: hazard ratio [HR] = 1.43, 95% CI = 1.08 to 1.90, = 0.015). The yellow-orange cluster was inversely associated with all-cause mortality (tertile 3 vs. tertile 1: HR = 0.78, 95% CI = 0.63 to 0.97, = 0.028) and CVD mortality (tertile 2 vs. tertile 1: HR = 0.57, 95% CI = 0.42 to 0.77, = 0.005). The orange-blue cluster (composed of antibodies against and ) was inversely associated with all-cause mortality (tertile 3 vs. tertile 1: HR = 0.65, 95% CI = 0.55 to 0.78, < 0.0001) and CVD mortality (tertile 3 vs. tertile 1: HR = 0.65, 95% CI = 0.47 to 0.88, = 0.007). These antibodies could predict prognosis or be potential intervention targets to prevent systemic effects of periodontal disease if further studies establish a causal relationship.
Topics: Actinomyces; Adult; Aged; Antibodies, Bacterial; Cardiovascular Diseases; Diabetes Mellitus; Female; Humans; Hyperglycemia; Male; Middle Aged; Nutrition Surveys; Periodontitis; Risk Factors
PubMed: 31634041
DOI: 10.1177/0022034519884012 -
JDR Clinical and Translational Research Apr 2020Periodontitis is a chronic inflammatory condition initiated by microorganisms and is positively linked to systemic conditions such as cancer, cardiovascular disease, and...
INTRODUCTION
Periodontitis is a chronic inflammatory condition initiated by microorganisms and is positively linked to systemic conditions such as cancer, cardiovascular disease, and diabetes mellitus.
OBJECTIVES
To prospectively investigate associations between empirically derived clusters of IgG antibodies against 19 selected periodontal microorganisms and cancer mortality in a representative sample of the US population.
METHODS
We evaluated 6,491 participants aged ≥40 y from the Third National Health and Nutrition Examination Survey (1988 to 1994), who had complete data on IgG antibody titers against 19 selected periodontal microorganisms and were free of cardiovascular disease and cancer. In a prior study, antibodies were categorized into 4 mutually exclusive groups via cluster analysis: red-green, orange-red, yellow-orange, and orange-blue. Cluster scores were estimated by summing z scores of the antibody titers making up each cluster. Participants were followed up to death until December 31, 2011. Cox proportional hazard models were applied to estimate hazard ratios (HRs) and 95% CIs for all-cancer mortality by tertiles of cluster scores.
RESULTS
During follow-up for a median of 15.9 y, there were 2,702 deaths (31.3%), including 631 cancer-related deaths (8.1%). After adjusting for multiple confounders, the orange-blue cluster was inversely associated with cancer mortality (tertile 2 vs. tertile 1: HR = 0.67, 95% CI = 0.54 to 0.84; tertile 3 vs tertile 1: HR = 0.62, 95% CI = 0.46 to 0.84). The association between the yellow-orange cluster and all-cancer mortality was also inverse but not significant, and the orange-red cluster and the red-green cluster were not associated with all-cancer mortality.
CONCLUSIONS
Antibodies against Eubacterium nodatum and Actinomyces naeslundii may be novel predictors of cancer mortality. If further studies establish a causal relationship between these antibodies and cancer mortality, they could be targets to prevent possible systemic effects of periodontal disease with potential interventions to raise their levels.
KNOWLEDGE TRANSFER STATEMENT
Periodontal antibodies against Eubacterium nodatum and Actinomyces naeslundii were inversely associated with cancer mortality among adults followed up for an average of 16 y. Periodontal antibodies may predict cancer mortality.
Topics: Actinomyces; Antibodies, Bacterial; Humans; Immunoglobulin G; Neoplasms; Periodontitis
PubMed: 31277564
DOI: 10.1177/2380084419859484 -
Infection and Immunity Nov 1979Rapid agglutination of Actinomyces viscosus and Actinomyces naeslundii cells by D-mannose solutions was observed during studies of their attachment to mammalian cells in...
Rapid agglutination of Actinomyces viscosus and Actinomyces naeslundii cells by D-mannose solutions was observed during studies of their attachment to mammalian cells in vitro. The specificity of the agglutination reaction was studied by slide agglutination tests and by measuring the rate of decrease in optical density of bacterial phosphate buffer suspensions caused by the setting of bacterial aggregates. Actinomyces cells were agglutinated by protein-containing mannose solutions of several chemical suppliers. Solutions of sugars other than D-mannose and solutions of mannitol and mannan all failed to agglutinate A. viscsus and A. naeslundii. "Mannose-enhanced" agglutination was impaired by boiling or autoclaving the mannose but was not affected by heating the bacteria, the presence of chloramphenicol, running the assay in the cold, or incorporating any of several commercially purchased sugars in the reaction mixture. During these hapten inhibition experiments, only 6-deoxy-L-talcose-containing extracts of an A. viscosus strain retarded the rate of mannose-enhanced agglutination. Protein-containing fractions of D-mannose mother liquors also agglutinated cells of A. viscosus and A. naeslundii. Other species of oral gram-positive rods were not agglutinated by mannose solutions. Together the data indicate that plant seed-derived D-mannose contains a protein-associated agglutinin for A. viscosus and A. naeslundii which may function via a "lectin-like" selective affinity for the unique cell wall sugar 6-deoxy-L-talose.
Topics: Actinomyces; Agglutination Tests; Agglutinins; Glucose; Hot Temperature; Mannose; Solutions; Stereoisomerism
PubMed: 546781
DOI: 10.1128/iai.26.2.427-434.1979 -
Infection and Immunity Jun 1979Coaggregation reactions between actinomycete and streptococcal cells occurred frequently when human strains of Actinomyces viscosus or A. naeslundii were mixed with...
Coaggregation reactions between actinomycete and streptococcal cells occurred frequently when human strains of Actinomyces viscosus or A. naeslundii were mixed with human isolates of Streptococcus sanguis or S. mitis, but were infrequent with other oral actinomycetes and streptococci. Two groups of actinomycetes and four groups of streptococci were defined by the patterns of their coaggregation reactions and by the ability of beta-linked galactosides (i.e., lactose) to reverse these reactions. Coaggregations occurred by one of the following three kinds to cell-cell interactions: (i) coaggregation that was blocked by heating the streptococcus but not the actinomycete and was not reversed by lactose; (ii) coaggregation that was blocked by heating the actinomycete but not the streptococcus and was reversed by lactose; and (iii) coaggregation that was blocked only by heating both cell types. The latter reaction was a combination of the first two since lactose reversed coaggregation between heated streptococci and unheated actinomycetes but did not reverse coaggregations between unheated streptococci and heated actinomycetes. Cells that could be heat inactivated also were inactivated by amino group acetylation or protease digestion, whereas cells that were unaffected by heat were not inactivated by these treatments. Coaggregation reactions of each kind were Ca2+ dependent and insensitive to dextranase treatment. These findings are consistent with the hypothesis that human strains of A. viscosus and A. naeslundii coaggregate with strains of S. sanguis and S. mitis by a system of specific cell surface interactions between protein or glycoprotein receptors on one cell type and carbohydrates on the other type.
Topics: Acetylation; Actinomyces; Calcium; Dextranase; Dextrans; Fructans; Hot Temperature; Humans; Lactose; Peptide Hydrolases; Streptococcus; Streptococcus mutans; Streptococcus sanguis
PubMed: 468376
DOI: 10.1128/iai.24.3.742-752.1979