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Establishment and distribution of Actinomyces viscosus and Actinomyces naeslundii in the human oral cavity.

The intraoral establishment and proportional distribution of suspected periodontal pathogens Actinomyces viscosus and Actinomyces naeslundii were studied using a recently developed differential plating medium, CNAC-20. Saliva and dental plaque samples were collected from 108 subjects ranging in age from infants to young adults; tongue and buccal mucosa samples were collected from only the adult subjects. Catalase-negative A. naeslundii was isolated from 40% of the predentate infants' and almost all other subjects' saliva samples. It predominated among CNAC-20 isolates in the saliva of subjects of all age groups, in the plaques of young children, and in the adult tongue samples. In contrast, catalase-positive A. viscosus was not isolated from predentate infant samples, and its frequency of isolation increased slowly with age (greater than 50% detection by age 7). A. viscosus was isolated in highest relative proportions from dental plaque and buccal mucosa samples. The two closely related species A. viscosus and A. naeslundii apparently differ in respect to factors determining the host age at which they colonize and their relative intraoral distribution in humans.

Actinomyces↗

Differences in the adsorptive behavior of human strains of Actinomyces viscosus and Actinomyces naeslundii to saliva-treated hydroxyapatite surfaces.

Human strains of Actinomyces viscosus and A. naeslundii differ in the time of their appearance and in their patterns of colonization in the mouth. Strains of these organisms were found to differ in their abilities to adsorb to saliva-treated hydroxyapatite (S-HA) surfaces, thought to mimic the teeth, and these differences parallel their patterns of colonizing the dentition. Thus, strains of A. viscosus tended to adsorb in higher numbers to hydroxyapatite (HA) treated with saliva of older children and adults than with saliva of younger children (ages 6 to 11). These salivary changes may account for the increased frequency with which this organism can be isolated from the mouths of children as they grow older. In contrast, strains of A. naeslundii and Streptococcus mutans did not show a preference for attaching to either type of S-HA. Strains of A. viscosus also generally adsorbed in higher numbers than A. naeslundii to HA treated with adult saliva; this may explain why higher proportions of A. viscosus are usually recoverable from the teeth of adults, even though A. naeslundii is generally present in higher proportions in saliva. Significant variation was noted between strains and between saliva samples collected from different donors. The differences in adsorptive behavior of strains of these species suggests that they are binding to different receptors in the salivary glycoprotein coating on HA surfaces. Adsorption of A. naeslundii ATCC 12104 was enhanced when S-HA was pretreated with neuraminidase, but this had little effect upon the adsorption of other Actinomyces strains tested. Adsorption of strain ATCC 12104 to S-HA was also strongly inhibited by fructose and sucrose and weakly inhibited by glucose, maltose, galactose, and lactose. However, other strains of A. naeslundii tested were affected less, or not at all, by these sugars. Adsorption of two strains of A. viscosus was not affected by any of the sugars or amines tested.

Actinomyces↗

Influence of growth medium on adsorption of Streptococcus mutans, Actinomyces viscosus, and Actinomyces naeslundii to saliva-treated hydroxyapatite surfaces.

The influence of the growth medium on the ability of strains of Streptococcus mutans, Actinomyces viscosus and A. naeslundii to attach to saliva-treated hydroxyapatite (S-HA) surfaces was studied. Preliminary experiments indicated that cells of each species harvested in lag, log, and early stationary phases of growth adsorbed comparably to S-HA; thus, early stationary phase cells were used in all subsequent assays. Strains were grown in chemically defined medium (CDM), in CDM supplemented with gastric mucin or with filter-sterilized or (60)Co-irradiated saliva from human donors of blood types A, B, or O, and in Trypticase soy broth (BBL Microbiology Systems) and Todd-Hewitt broth. Adherence of S. mutans H12 to S-HA tended to vary when the streptococci were grown in saliva-supplemented CDM, but the number of cells which attached was generally within twofold of that of CDM-grown cells. Attachment of A. viscosus S2 and LY7 and of A. naeslundii S4 and L13 was generally similar when grown in CDM or in CDM supplemented with saliva, but it tended to increase for organisms grown in CDM supplemented with gastric mucin. None of the strains studied appeared to destroy the blood group reactivity of the added salivary components, and they attached equally well to HA treated with homologous or heterogous saliva from that present in the medium in which they were grown. The A. viscosus strains adsorbed in 25 to 40% higher numbers to HA treated with blood type B saliva than with type A saliva, irrespective of the medium used for growth. S. mutans H12 cells displayed alpha- and beta-glucosidase and alpha-galactosidase activity; the Actinomyces strains exhibited these activities plus beta-galactosidase when grown in all media. However, the levels of these glycoside hydrolases did not correlate with cell adsorption to S-HA. The apparent weak influence of the growth medium on attachment of S. mutans was studied further. Strains of S. mutans isolated from the saliva of five human donors were made resistant to streptomycin, grown in CDM, and then added to new saliva samples from the respective donors from which they were obtained. The in vitro-grown cells were found to attach to S-HA comparably to S. mutans cells present naturally in the saliva.

ABO Blood-Group System↗

Isolation and characterization of coaggregation-defective mutants of Actinomyces viscosus, Actinomyces naeslundii, and Streptococcus sanguis.

Spontaneously occurring coaggregation-defective (COG-) mutants of oral actinomycetes and streptococci were isolated and used to study interactions between cells of these two kinds of bacteria. COG- mutants of each kind of bacteria were isolated by a simple enrichment scheme. Parent strains were mixed with a coaggregating partner strain, coaggregated cells were removed by low-speed centrifugation, and non-coaggregated cells were recycled by the addition of more partner strain cells. COG- mutants constituted up to 10% of the parent strain cell type in the final enriched cell suspension. Unlike their respective parent strains, COG- mutants of Actinomyces viscosus T14V and Actinomyces naeslundii ATCC 12104, and A. naeslundii I exhibited no lactose-reversible coaggregation with certain oral Streptococcus sanguis strains. However, these COG- mutants were not altered in their coaggregations with another S. sanguis strain, H1, a member of a streptococcal coaggregation group that exhibits only lactose-nonreversible coaggregations with oral actinomycetes. Although all coaggregations between S. sanguis H1 and these actinomycetes appear to be alike, examination of a COG- mutant of S. sanguis H1 revealed that, like its parent, it coaggregated with A. viscosus T14V and its COG- mutants, but unlike its parent, it did not coaggregate with the two A. naeslundii strains or their COG- mutants. Thus, it was concluded that at least two types of surface components are important in mediating coaggregation between S. sanguis H1 and actinomycetes. The COG- mutant of S. sanguis allowed detection of these components, which were indistinguishable in previous studies.

Actinomyces↗

Structural preferences of beta-galactoside-reactive lectins on Actinomyces viscosus T14V and Actinomyces naeslundii WVU45.

Specificities of lectins on Actinomyces viscosus T14V and Actinomyces naeslundii WVU45 were compared by measuring the abilities of D-galactose, N-acetyl-D-galactosamine, 14 beta-D-galacto-oligosaccharides, and 2 beta-D-fuco-oligosaccharides to inhibit coaggregation between Streptococcus sanguis 34 and each actinomycete. Inhibition profiles were similar, but WVU45 was significantly more sensitive to several inhibitors. D-Galactose-beta(1 leads to 3)-N-acetyl-D-galactosamine glycosides were most potent.

Actinomyces↗

Relative hydrophobicities of Actinomyces viscosus and Actinomyces naeslundii strains and their adsorption to saliva-treated hydroxyapatite.

The present study examined 42 strains of Actinomyces spp. to determine whether adsorption to saliva-treated hydroxyapatite (SHA) of the selected strains of this prominent group of dental-plaque bacteria correlated with hydrophobicity. The relative hydrophobicity of the strains was determined by their adsorption to hydrophobic gels (i.e., phenyl-Sepharose) and their aggregation in ammonium sulfate. Within serogroups the relative hydrophobicity for the strains was similar. The relative adsorption of strains to SHA was also similar within the respective serogroups. Strains which were relatively hydrophobic, as judged by their binding to the hydrophobic gel and aggregation in low concentrations of ammonium sulfate, adsorbed well to SHA. Strains which adsorbed poorly to SHA were relatively hydrophilic since they did not bind well to the hydrophobic gel and were only aggregated in relatively high concentrations of ammonium sulfate. Tween 80, a nonionic detergent known to inhibit hydrophobic interactions, blocked binding of cells to the hydrophobic gel, suggesting that hydrophobic interactions had been inhibited. However, Tween 80 exhibited no influence on the adsorption of cells to SHA. Thus, although there was a strong statistical correlation between the relative hydrophobicity of a strain and its adsorption to SHA, the data were consistent with the view that other interactions, such as ionic bonds and interactions between complimentary macromolecules, are involved in adsorption of the Actinomyces strains to SHA.

Actinomyces↗

Development of a selective medium for detection and enumeration of Actinomyces viscosus and Actinomyces naeslundii in dental plaque.

A selective medium (CFAT) was developed for the detection and enumeration of Actinomyces viscosus and Actinomyces naeslundii in dental plaque. Neutral acriflavin and potassium tellurite were used in combination with the known selective agents cadmium and fluoride to eliminate most of the competing plaque flora. Composition of CFAT per liter was as follows: Trypticase soy broth (BBL Microbiology Systems), 30 g; glucose, 5 g; agar, 15 g' cadmium sulfate, 13 mg; sodium fluoride, 85 mg; neutral acriflavin, 1.20 mg; potassium tellurite, 2.50 mg; basic fuchsin, 1.25 mg; defibrinated sheep blood, 50 ml. A. viscosus reference strains of human origin grew on CFAT without reduction in numbers under an atmosphere of 90% air-10% CO2. Animal strains of A. viscosus were inhibited at the level of cadmium in CFAT. Two of six A. naeslundii strains did not grow on CFAT. Improved recovery of A. viscosus and A. naeslundii from dental plaque occurred on CFAT, as compared with two other selective media which contained either cadmium sulfate or sodium fluoride, respectively, as selective agents. CFAT was more selective with regard to much of the extraneous gram-positive flora. Bacterionemia, Neisseria, yeasts, and streptococci were virtually eliminated.

Actinomyces↗

Assignment of Actinomyces viscosus and Actinomyces naeslundii strains to numerical taxonomy clusters by immunofluorescence based on antifibril antisera.

A previous observation, using a few representative laboratory strains, that rabbit antisera raised against isolated surface fibrils might be useful in identifying Actinomyces viscosus and Actinomyces naeslundii isolates to their correct numerical taxonomy clusters was reexamined with a large culture collection, including clinical isolates from three different laboratories. Strains were first identified by a slower standard procedure, including agglutination with anti-whole-cell antisera, catalase test, and gas and paper chromatography as needed. Indirect immunofluorescence tests indicated that antisera raised against fibrils of strains representing the three principal taxonomic clusters could separate most strains into their correct clusters. The antisera were particularly successful in separating two taxonomically distinct groups of A. naeslundii, clusters 3 and 5, but could not separate A. viscosus belonging to the principal cluster (no. 1) and minor clusters (no. 2, 4, 6).

Actinomyces↗

Glycogen synthetic abilities of Actinomyces viscosus and Actinomyces naeslundii freshly isolated from dental plaque over root surface caries lesions and non-carious sites.

Relative glycogen synthetic abilities of resting cells of fresh clinical isolates of Actinomyces viscosus and Actinomyces naeslundii originating from dental plaque samples over root surface caries lesions and non-carious sites were studied under anaerobic conditions at a constant pH of 7.0, with U-(14C)-glucose used as the carbon source. Although the rates of glucose utilization and total acid formation were essentially the same, A. viscosus strains isolated from root surface caries lesions showed glycogen synthetic abilities approximately two to seven times higher than did A. viscosus strains originating from non-carious sites, and also two to four times higher than did A. naeslundii strains originating from both carious and non-carious sites.

Acids↗

Characterization of the binding of Actinomyces naeslundii (ATCC 12104) and Actinomyces viscosus (ATCC 19246) to glycosphingolipids, using a solid-phase overlay approach.

Actinomyces naeslundii (ATCC 12104) and Actinomyces viscosus (ATCC 19246) were radiolabeled externally (125I) or metabolically (35S) and analyzed for their ability to bind glycosphingolipids separated on thin layer chromatograms or coated in microtiter wells. Two binding properties were found and characterized in detail. (i) Both bacteria showed binding to lactosylceramide (LacCer) in a fashion similar to bacteria characterized earlier. The activity of free LacCer was dependent on the ceramide structure; species with 2-hydroxy fatty acid and/or a trihydroxy base were positive, while species with nonhydroxy fatty acid and a dihydroxy base were negative binders. Several glycolipids with internal lactose were active but only gangliotriaosylceramide and gangliotetraosylceramide were as active as free LacCer. The binding to these three species was half-maximal at about 200 ng of glycolipid and was not blocked by preincubation of bacteria with free lactose or lactose-bovine serum albumin. (ii) A. naeslundii, unlike A. viscosus, showed a superimposed binding concluded to be to terminal or internal GalNAc beta and equivalent to a lactose-inhibitable specificity previously analyzed by other workers. Terminal Gal beta was not recognized in several glycolipids, although free Gal and lactose were active as soluble inhibitors. The binding was half-maximal at about 10 ng of glycolipid. A glycolipid mixture prepared from a scraping of human buccal epithelium contained an active glycolipid with sites for both binding specificities.

Actinomyces↗

[Characteristics of the ultrastructural organization of Actinomyces rimosus and Actinomyces violocinereus in monocultures and in an association producing extracellular proteases].

The ultrastructural organization of Actinomyces rimosus and Actinomyces violocinereus was compared in monocultures and in associations. The cells of the two species can be discriminated by certain cytological characteristics. A rimosus predominated under the studied conditions and periods of growth. This organism had growth processes disordered (intrahyphal growth). A. violocinereus was characterized by the following processes in the association: peptidoglycan hypersynthesis, formation of calloses of the cell wall which occurred in parallel to hypertrophy of mesosomes, a loss of the capability to form capsules, and delayed spore formation. The reduced synthesis of granular and fibrillar material indicated that these products were not associated with exoprotease. The enzymatic activity was higher and could be detected in earlier in the association than in the monoculture of A. rimosus.

Actinomyces↗

[A case of pulmonary actinomycosis, who expectorated sulfur granules, caused by Actinomyces odontolyticus and Actinomyces meyeri].

A 51-year-old man complaining of cough and bloody sputum, was admitted to our hospital because of antibiotic-resistant chronic pneumonia in the right upper lobe. Initially, bronchoscopic examination and sputum culture revealed no evidence of malignancy or any specific infection, either pathologically or microbiologically. However, pathological examination of a solid body expectorated with sputum revealed typical sulfur granules, indicating pulmonary actinomycosis. Two actinomyceses named Actinomyces odontolyticus and Actinomyces meyeri were detected later. Pulmonary infection caused by these types of actinomyceses is rare, and the diagnostic procedure seemed to be unusual.

Actinomycosis↗

[Population composition of Actinomyces tumemacerans and Actinomyces albus var. fungatus].

The population analysis of Actinomyces tumemacerans and Actinomyces albus var. fungatus has revealed identical homologous series of spontaneous variants, this suggesting the genetical relationship of the cultures. Variants of the same type (basic, oligosporous, asporogenous and proactinomycete-like) are identical not only according to their individual properties (Kuznetsov, 1973) but also in total characteristics typical of the variants of a given species. Populations of the studied cultures comprise variants synthesizing several antibiotics, i.e. albofungin, albonursin and tetraene (basic and oligosporous variants), albofungin and tetraene (asprogenous green variants), as well as variants producing only one tetraene antibiotic (proactinomycete-like variants). Therefore, the population analysis based on the law of homologous series in hereditary variability of actinomycetes can be used as a new approach to the taxonomy of these microorganisms.

Anti-Bacterial Agents↗

Biochemical and biological characterizations and ribotyping of Actinomyces pyogenes and Actinomyces pyogenes-like organisms from liver abscesses in cattle.

Actinomyces pyogenes is the second most frequently encountered pathogen, next only to Fusobacterium necrophorum, in liver abscesses of feedlot cattle. Ninety-one isolates, presumptively identified as A. pyogenes, isolated from liver abscesses of cattle were studied. Biochemical characteristics determined by the API 20 Strep kit were similar to those reported previously for A. pyogenes isolated from other infections, except that 18% of isolates hydrolyzed esculin. Nine isolates that resembled A. pyogenes in morphology and in certain biochemical characteristics, but fermented mannitol and/or raffinose, were called A. pyogenes-like (APL) organisms. The five antimicrobial agents, bacitracin, chlortetracycline, oxytetracycline, tylosin, and virginiamycin were inhibitory to all strains of A. pyogenes and APLs. Generally, APL organisms had higher mean hemolytic and leukotoxic activities than A. pyogenes. All isolates of A. pyogenes and APLs produced proteases and neuraminidases. Ribotyping with endonucleases, including BstEII, ClaI, EcoRI, EcoRV, HaeIII, MboI, PvuII, SalI, and SmaI alone or in combinations, showed considerable genetic heterogeneity in both A. pyogenes and APLs. No specific ribopattern characteristic of each group was observed with any of the endonuclease used. The origin of A. pyogenes and APLs and the relative importance of APLs in causing liver abscesses in feedlot cattle are not known.

Actinomyces↗

Inhibition of adherence of Actinomyces naeslundii (Actinomyces viscosus) T14V-J1 to saliva-treated hydroxyapatite by a monoclonal antibody to type 1 fimbriae.

A monoclonal antibody to Actinomyces naeslundii (A. viscosus) T14V-J1 type 1 fimbriae, capable of inhibiting the adherence of this bacterium to salivary proline-rich protein-treated hydroxyapatite, was generated by immunization of SWR mice with A. naeslundii 55-19, a strain derived from T14V-J1 that possess only type 1 fimbriae. Supernatants of hybridomas were screened for reactivity with purified type 1 fimbriae. An IgG monoclonal antibody, 86-49E, blocked the adsorption of the parent strain to proline-rich protein-treated hydroxyapatite by 77% with 1.0 microgram/ml of the monoclonal antibody; the Fab fragment derived from this monoclonal antibody inhibited adherence by 38% at the same concentration. Similarly, the adherence of strain 55-19 was inhibited by 100% and 64% to proline-rich protein-treated hydroxyapatite with 1.0 micrograms/ml of IgG and Fab fragments respectively. Control monoclonal antibody to the subunit of type 1 fimbriae, as well as to Actinobacillus actinomycetemcomitans caused only minimal adherence inhibition. Monoclonal antibody 86-49E also agglutinated both type 1 fimbriae-bearing strains of A. naeslundii T14V-J1 and 55-19 but not strains 59-51 and 147, which lack type 1 fimbriae. Further confirmation of the specificity of monoclonal antibody 86-49E was obtained using these fimbria-deficient mutant strains in an enzyme-linked immunosorbent assay, with the monoclonal antibody binding only to strains possessing type 1 fimbriae. Immunogold labeling in conjunction with electron microscopy suggested binding of monoclonal antibody 86-49E occurring near the distal end of the fimbriae. In contrast, when a monoclonal antibody specific for the type 1 fimbrial subunit but not capable of adherence inhibition was used together with 86-49E in double-labeling experiments, extensive labeling of the fimbriae by the subunit antibody was noted. These data suggest that a monoclonal antibody specific for the type 1 fimbriae of A. naeslundii that is capable of binding to a discrete site on the fimbriae has the capacity to inhibit the adsorption of this organism to saliva-treated hydroxyapatite.

Actinomyces viscosus↗

Comparative pathogenicity of Actinomyces naeslundii and Actinomyces israelii.

Typical actinomycosis has been produced in mice following single intraperitoneal injections of saline suspensions of Actinomyces israelii and A. naeslundii. A. israelii produced infections in 95.8% of the animals inoculated. A. naeslundii, generally considered to be a saprophytic organism, produced lesions in 89.7% of the inoculated animals. The finding that A. naeslundii produced lesions in mice similar to those produced by A. israelii suggests that A. naeslundii has similar pathogenic potential for man. The isolation of A. naeslundii from suppurative lesions of man also supports this conclusion.

Actinomyces↗