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Infection and Immunity Nov 1979Human A, B, and O erythrocytes (RBC) were agglutinated by many human strains of Actinomyces viscosus and A. naeslundii. At 37 degrees C, these bacterium-mediated...
Human A, B, and O erythrocytes (RBC) were agglutinated by many human strains of Actinomyces viscosus and A. naeslundii. At 37 degrees C, these bacterium-mediated hemagglutination reactions required the action of bacterial neuraminidase upon the RBC; however, at 4 degrees C, the requirement for neuraminidase was not as striking. Bacterial cell suspensions which caused hemagglutination at 37 degrees C contained both soluble extracellular and cell-associated neuraminidase activities as shown by enzyme assays using a soluble substrate (i.e., alpha 1-acid glycoprotein). Bacterium-mediated hemagglutination occurred only in the presence of soluble neuraminidase activity, and the rate of hemagglutination could be inhibited by 2-deoxy-2,3-dehydro-N-acetylneuraminic acid, a competitive inhibitor of purified soluble neuraminidase from A. viscosus T14V. Suspensions of bacteria which contained only cell-associated neuraminidase activity were unable to initiate hemagglutination, but they caused immediate hemagglutination when mixed with neuraminidase-treated RBC. All hemagglutination reactions were reversible in the presence of 0.02 M lactose and were abolished by heating (85 degrees C for 30 min) the actinomycete cells but not the RBC. The proposed mechanism of hemagglutination involves two sequential steps: (i) the action of neuraminidase to unmask galactose-containing receptors on the RBC and (ii) the multivalent binding of these receptors by many low-affinity lection sites on the bacterial surface.
Topics: Actinomyces; Chemical Phenomena; Chemistry; Clostridium perfringens; Cold Temperature; Dental Plaque; Erythrocytes; Glycoproteins; Hemagglutination; Humans; Neuraminidase; Sialic Acids; Solubility; Species Specificity
PubMed: 232691
DOI: 10.1128/iai.26.2.563-572.1979 -
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 -
Infection and Immunity Nov 1984The adherence of Actinomyces naeslundii WVU45 to monolayer cultures of human epithelial cell lines was mediated by the lactose-sensitive fimbriae (type 2) of strain...
The adherence of Actinomyces naeslundii WVU45 to monolayer cultures of human epithelial cell lines was mediated by the lactose-sensitive fimbriae (type 2) of strain WVU45. The attachment of Actinomyces viscosus T14V, which has both types 1 and 2 fimbriae, was approximately half that of A. naeslundii, and only minimal attachment of A. naeslundii and A. viscosus mutants lacking type 2 fimbriae was detected. The adherence of strain WVU45 was enhanced two- to threefold by neuraminidase treatment of the epithelial cells. The Fab fragments of antibodies which recognize the type 2 fimbriae inhibited the adherence of A. naeslundii WVU45 to the epithelial cells. The bacterial interaction with epithelial cells was inhibited by lactose, methyl-beta-D-galactoside, and N-acetyl-D-galactosamine, but not by methyl-alpha-D-galactoside, cellobiose, N-acetyl-D-glucosamine, L-fucose, or D-mannose. To further characterize the epithelial cell receptors for the bacterial lectin, we utilized several plant and invertebrate lectins as potential inhibitors of bacterial adherence. Lectins from Bauhinia purpurea and Arachis hypogaea which recognize N-acetyl-D-galactosamine, D-galactose, and D-galactose-beta-(1----3)-N-acetyl-D-galactosamine inhibited bacterial attachment, and binding of these lectins to epithelial cells was enhanced by the addition of neuraminidase. Lectins reacting with alpha-linked D-galactose, alpha-linked N-acetyl-D-galactosamine, D-mannose, or sialic acid were not inhibitory. Under similar assay conditions, adherence of a mannose-sensitive strain of Escherichia coli was inhibited by concanavalin A but not by the lectin from Bauhinia purpurea. These results indicate that certain plant lectins have specificities similar to that of the actinomyces fimbrial lectin and are, therefore, useful probes for identifying receptors on epithelial cells for certain bacteria.
Topics: Actinomyces; Adhesiveness; Carbohydrate Sequence; Cells, Cultured; Epithelium; Fimbriae, Bacterial; Humans; Microvilli; Receptors, Mitogen
PubMed: 6150008
DOI: 10.1128/iai.46.2.459-464.1984 -
Caries Research 1998The isolation of Actinomyces naeslundii from sound, exposed root surfaces (n = 56) and soft and leathery root carious lesions (n = 71) was investigated. Root carious...
The isolation of Actinomyces naeslundii from sound, exposed root surfaces (n = 56) and soft and leathery root carious lesions (n = 71) was investigated. Root carious lesions were sampled after the removal of overlying plaque. Supragingival plaque or carious dentine was sampled using a sterile excavator, the samples were disaggregated and cultured on both selective and non-selective media. A. naeslundii isolates were identified to the genospecies using specific antisera. Significantly greater numbers and proportions of A. naeslundii genospecies 2 than A. naeslundii genospecies 1 were isolated from all sites sampled. There was no significant difference between the numbers and proportions of the two genospecies isolated from leathery and soft lesions. The relationship between the presence of A. naeslundii genospecies and aciduric and acidogenic organisms was investigated. Those sound exposed root surfaces from which A. naeslundii genospecies 1 and/or 2 were isolated yielded significantly lower numbers of lactobacilli and yeasts than the surfaces from which A. naeslundii were not isolated. This difference was also found in leathery lesions but not soft root carious lesions. The microflora of soft root carious lesions was found to comprise primarily gram-positive pleomorphic rods which formed 70+/-7.8% of the flora, while in plaque from exposed root surfaces and in infected dentine from leathery lesions the gram-positive pleomorphic rods represented only 35% of the flora.
Topics: Actinomyces; Analysis of Variance; Bacterial Typing Techniques; Case-Control Studies; Chi-Square Distribution; Colony Count, Microbial; Dental Plaque; Dentin; Gram-Positive Rods; Humans; Root Caries
PubMed: 9544857
DOI: 10.1159/000016438 -
Journal of Clinical Microbiology Oct 1975A medium for detecting colonies of Actinomyces viscosus and Actinomyces naeslundii in dental plaque samples was developed. The medium (CNAC-20) contains 20.0 mug of...
A medium for detecting colonies of Actinomyces viscosus and Actinomyces naeslundii in dental plaque samples was developed. The medium (CNAC-20) contains 20.0 mug of 3CdSO4-8H2O per ml of Columbia CNA agar base. Laboratory strains of A. viscosus grew on CNAC-20 in characteristic round, white, smooth, opaque colonies. Increasing the cadmium concentration impaired the growth of some A. viscosus strains. Stock strains of A. naeslundii and A. israelii grew in colonies of similar white, opaque morphology. The few strains of other gram-positive plaque bacteria that grew on CNAC-20 had colonies easily distinguished from those of A. viscosus. Most of the bacterial strains freshly isolated from Actinomyces-like colonies on CNAC-20 that had been inoculated with human dental plaque samples were found to have cultural characteristics consistent with previous descriptions of A. viscosus or A. naeslundii. CNAC-20 may facilitate investigations into the relationship of microaerophilic Actinomyces with the etiology of dental diseases.
Topics: Actinomyces; Actinomycetaceae; Cadmium; Culture Media; Dental Plaque; Humans; Lactobacillus; Periodontal Diseases; Streptococcus
PubMed: 1184734
DOI: 10.1128/jcm.2.4.305-310.1975 -
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 -
Journal of Periodontology Feb 2005Gravida's poor periodontal health is emerging as a modifiable independent risk factor for preterm delivery and low birth weight.
BACKGROUND
Gravida's poor periodontal health is emerging as a modifiable independent risk factor for preterm delivery and low birth weight.
METHODS
To test the hypothesis that oral bacteria other than periodontal pathogens are also associated with pregnancy outcomes, specific oral bacterial levels measured during pregnancy were evaluated in relation to gestational age and birth weight while controlling for demographic, medical, and dental variables. The study population consisted of 297 predominantly African- American women who were pregnant for the first time. The salivary bacterial levels evaluated were Streptococcus mutans, Streptococcus sobrinus, Streptococcus sanguinus, Lactobacillus acidophilus, Lactobacillus casei, Actinomyces naeslundii genospecies (gsp) 1 and 2, total streptococci, and total cultivable organisms.
RESULTS
For 1 unit increase in log(10) A. naeslundii gsp 2 levels, there was a 60 gm decrease in birth weight (beta = -59.7 g; SE = 29.1; P = 0.04), and a 0.17 week decrease in gestational age (beta = -0.17 wk; SE = 0.09; P = 0.05). In contrast, per 1 unit increase in log(10) L. casei levels, there was a 42 gm increase in birth weight (beta = 42.2 g; SE = 19.3; P = 0.03), and a 0.13 week increase in gestational age (beta = 0.13 week; SE = 0.06; P = 0.04).
CONCLUSIONS
We conclude that other oral bacterial species can also be related to pregnancy outcomes in addition to previously reported periodontal pathogens. These organism levels may not only predict poor pregnancy outcomes, but also be used as modifiable risk factors in reducing prematurity and low birth weight.
Topics: Actinomyces; Adult; Black or African American; Analysis of Variance; Colony Count, Microbial; Female; Humans; Infant, Low Birth Weight; Infant, Newborn; Lacticaseibacillus casei; Linear Models; Male; Pregnancy; Pregnancy Complications, Infectious; Pregnancy Outcome; Premature Birth; Prognosis; Saliva
PubMed: 15974839
DOI: 10.1902/jop.2005.76.2.171 -
Infection and Immunity Sep 1980A standardized assay was used to measure the attachment of Actinomyces naeslundii ATCC 12104 to washed human buccal epithelial cells. Treatment of the A. naeslundii...
A standardized assay was used to measure the attachment of Actinomyces naeslundii ATCC 12104 to washed human buccal epithelial cells. Treatment of the A. naeslundii cells with hyaluronidases, wheat germ lipase, protease, trypsin, heat, or sonic oscillation significantly reduced their ability to attach to epithelial cells. Treatment of the epithelial cells with the above enzymes did not influence the attachment of A. naeslundii. Extraction of A. naeslundii with NaOH also significantly reduced the ability of the bacterium to attach to human buccal epithelial cells. The neutralized and dialyzed NaOH extract contained both carbohydrate and protein substances in a ratio of about 1:1. Adding this extract back to the extracted bacterial cells partially restored their ability to attach to epithelial cells. When the NaOH extract was preincubated with epithelial cells and residual extract was removed by washing, attachment of normal A. naeslundii was partially blocked. The ability of the extracted material to block attachment was significantly reduced when treated with hyaluronidases or with wheat germ lipase. Treatment with heat, protease, or trypsin did not significantly reduce the ability of the extracted materials to block attachment. Pretreatment of the epithelial cells with hyaluronic acid or chondroitin sulfate also reduced subsequent attachment of normal A. naeslundii cells. Pretreatment of epithelial cells with dextrans, proteins, or unpure mannose did not influence subsequent attachment of A. naeslundii. Pretreatment of A. naeslundii with galactose and lactose significantly inhibited attachment to normal epithelial cells. The results suggest that the attachment of A. naeslundii to human buccal epithelial cells may involve mucopolysaccharides similar to hyaluronic acid on the surface of the bacterial cells. Other attachment mechanisms may also be operative.
Topics: Actinomyces; Binding Sites; Carbohydrates; Cheek; Epithelium; Humans; Hyaluronoglucosaminidase; Lipase; Peptide Hydrolases; Sodium Hydroxide; Temperature; Time Factors; Trypsin
PubMed: 7000708
DOI: 10.1128/iai.29.3.981-989.1980 -
Infection and Immunity Jan 1981Human 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... (Comparative Study)
Comparative Study
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.
Topics: Actinomyces; Adsorption; Adult; Amines; Carbohydrates; Child; Humans; Hydroxyapatites; Neuraminidase; Saliva; Species Specificity
PubMed: 7216448
DOI: 10.1128/iai.31.1.261-266.1981 -
Oral Microbiology and Immunology Dec 1994The initial steps of sorbitol catabolism were studied in 4 strains of Actinomyces naeslundii and Actinomyces viscosus that had been isolated from human dental plaque....
The initial steps of sorbitol catabolism were studied in 4 strains of Actinomyces naeslundii and Actinomyces viscosus that had been isolated from human dental plaque. Cell-free extracts were prepared from cells grown in the presence of either sorbitol, xylitol or glucose. The extracts from all strains grown on sorbitol had nicotinamide adenine dinucleotide-linked dehydrogenase activities for sorbitol and xylitol and reduced nicotinamide adenine dinucleotide-linked reductase activities for fructose and xylulose. Two of the strains also exhibited these activities when grown in the presence of xylitol, and all glucose-grown cells lacked them. The results indicate that sorbitol metabolism in oral actinomyces involve oxidation of sorbitol to fructose by an inducible enzyme, nicotinamide adenine dinucleotide-linked sorbitol dehydrogenase. This step is followed by the phosphorylation of fructose with guanosine triphosphate as a main phosphoryl donor. Thus, the initial catabolic pathway of sorbitol in A. naeslundii and A. viscosus is different from those described for other oral bacteria.
Topics: Actinomyces; Actinomyces viscosus; Enzyme Induction; Fructosephosphates; Hexokinase; L-Iditol 2-Dehydrogenase; NAD; NADH, NADPH Oxidoreductases; Oxidoreductases; Sorbitol
PubMed: 7870473
DOI: 10.1111/j.1399-302x.1994.tb00288.x