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PubMed1987

Intergeneric bacterial coaggregations involving mutans streptococci and oral actinomyces.

Mutans streptococci (MS) representing eight different serotypes were tested for their ability to coaggregate in vitro with oral actinomyces and other streptococcal species. Of the mutans streptococci tested, only strains of S. cricetus (formerly S. mutans serotype a) displayed pronounced coaggregations and only with certain strains of actinomyces. S. cricetus coaggregated, by lactose nonreversible mechanisms, with serotype 4 Actinomyces naeslundii WVU963 and WVU924 and with serotype 2 Actinomyces odontolyticus WVU758. The first pair was disaggregated by protein denaturants (e.g., sodium dodecyl sulfate and urea) and EDTA. This coaggregation was inhibited when the streptococcal, but not the actinomyces, partner was pretreated with either heat or protease, suggesting the presence of a protein mediator on only the streptococcal cell surface. The S. cricetus-A. odontolyticus coaggregation appeared to involve protein components on each cell, as shown by the lack of coaggregation after pretreatment of either cell type with heat or proteases. This coaggregation was also reversed by sodium dodecyl sulfate and urea, as well as by sodium deoxycholate, but not by EDTA. The data indicate that different mechanisms may be involved in each of these coaggregations.

Actinomyces↗
PubMed1988

Use of lytic bacteriophage for Actinomyces viscosus T14V as a probe for cell surface components mediating intergeneric coaggregation.

A lytic bacteriophage for Actinomyces viscosus T14V (the reference strain for actinomyces coaggregation group A) was isolated from raw sewage. This phage, designated BF307, also lysed the T14V-derived nonfimbriated mutant PK455-2 as well as A. viscosus MG-1 and T14AV but not the other serotype 2 or serotype 1 strains of this species that were tested or any of nine Actinomyces naeslundii isolates. Phages BF307 belonged to Bradley morphological group C and was similar in appearance to the A. viscosus MG-1 phages Av-1 and Av-3, which do not productively infect A. viscosus T14V. A. viscosus MG-1 mutants selected for resistance to phage BF307, Av-3, or CT7 (a human dental plaque isolate with the same host range as BF307) were coresistant to the other two phages but sensitive to Av-1. These results indicate that the receptors on A. viscosus MG-1 for phages BF307, Av-3, and CT7 are identical or share a common precursor and that the receptor for phage Av-1 is distinct. Comparison of the genomes of BF307, Av-3, and CT7 revealed that their DNAs were similar in size but distinguishable by restriction analysis. Two altered coaggregation phenotypes were identified among the phage BF307-resistant mutants of strains MG-1, T14V, T14AV, and PK455-2. Class I mutants had lost the ability to interact with coaggregation group 1 streptococci, and class II mutants did not coaggregate with either group 1 or group 2 streptococci. These results are consistent with the proposal that the phage BF307 receptor on these A. viscosus strains is related to one of the structures that mediates coaggregation with oral streptococci. A model to delineate the various coaggregation mediators on the surface of actinomyces coaggregation group A cells is presented, and the use of these phages to probe surface components of human oral actinomyces strains is discussed.

Actinomyces↗
PubMed1988

Specific and nonspecific inhibition of adhesion of oral actinomyces and streptococci to erythrocytes and polystyrene by caseinoglycopeptide derivatives.

Various caseinoglycopeptide derivatives prepared from mammalian milk were evaluated as inhibitors of hemagglutinations mediated by Actinomyces viscosus Ny1, Streptococcus sanguis OMZ9, and, for comparative purposes, plant lectins from Arachis hypogaea and Bauhinia purpurea. It was found that recognition of the beta-D-galactose-(1----3)-2-acetamido-2-deoxy-D-galactose carbohydrate chain by Actinomyces viscosus Ny1 organisms and Arachis hypogaea and B. purpurea agglutinins had similar structural requirements; in all cases, the desialylated bovine caseinoglycomacropeptide, on which several units of the above mentioned disaccharide are clustered, behaved as the most potent hemagglutination inhibitor. By contrast, none of the preparations tested inhibited erythrocyte agglutination by S. sanguis OMZ9. Thus, the desialylated bovine caseinoglycomacropeptide acts as a potent and specific inhibitor of oral Actinomyces adhesion to cell membranes (a soft surface) and could be used as a probe for the study of recognition mechanisms mediated by Actinomyces galactose-binding lectins. During the present study, both native and desialylated variants of the same bovine glycomacropeptide also totally prevented the adhesion of Actinomyces viscosus Ny1, S. sanguis OMZ9, and S. mutans OMZ176 to polystyrene surfaces. Comparative evaluations of various structurally different compounds gave the following results. Neither mono- nor disaccharides related to caseinoglycopeptide carbohydrates prevented adhesion; highly positively or negatively charged polypeptides and polysaccharides were either not or only moderately active. Besides these glycomacropeptides, an inhibitory activity was also exhibited by other mucin-type glycoproteins carrying short O-linked carbohydrate chains (including bovine submaxillary mucin), polyethylene glycol, and bovine serum albumin. Consequently, caseinoglycopeptide prevention of oral bacterial adhesion to polystyrene tubes (a hard surface) takes place with no species specificity and can be compared to nonspecific inhibition exhibited by various polymers with very different structural characteristics.

Actinomyces↗
PubMed2001

Identification of clinical isolates of actinomyces species by amplified 16S ribosomal DNA restriction analysis.

Amplified 16S ribosomal DNA (rDNA) restriction analysis (ARDRA), using enzymes HaeIII and HpaII, was applied to 176 fresh and 299 stored clinical isolates of putative Actinomyces spp. referred to the Anaerobe Reference Unit of the Public Health Laboratory Service for confirmation of identity. Results were compared with ARDRA results obtained previously for reference strains and with conventional phenotypic reactions. Identities of some strains were confirmed by analysis of partial 16S rDNA sequences. Of the 475 isolates, 331 (70%) were clearly assigned to recognized Actinomyces species, including 94 isolates assigned to six recently described species. A further 52 isolates in 12 ARDRA profiles were designated as apparently resembling recognized species, and 44 isolates, in 18 novel profiles, were confirmed as members of genera other than Actinomyces. The identities of 48 isolates in nine profiles remain uncertain, and they may represent novel species of Actinomyces. For the majority of species, phenotypic results, published reactions for the species, and ARDRA profiles concurred. However, of 113 stored isolates originally identified as A. meyeri or resembling A. meyeri by phenotypic tests, only 21 were confirmed as A. meyeri by ARDRA; 63 were reassigned as A. turicensis, 7 as other recognized species, and 22 as unidentified actinomycetes. Analyses of incidence and clinical associations of Actinomyces spp. add to the currently sparse knowledge of some recently described species.

Actinomyces↗
PubMed2001

Phenotypic identification of Actinomyces and related species isolated from human sources.

Recent advancements in chemotaxonomic and molecular biology-based identification methods have clarified the taxonomy of the genus Actinomyces and have led to the recognition of several new Actinomyces and related species. Actinomyces-like gram-positive rods have increasingly been isolated from various clinical specimens. Thus, an easily accessible scheme for reliable differentiation at the species level is needed in clinical and oral microbiology laboratories, where bacterial identification is mainly based on conventional biochemical methods. In the present study we designed a two-step protocol that consists of a flowchart that describes rapid, cost-efficient tests for preliminary identification of Actinomyces and closely related species and an updated more comprehensive scheme that also uses fermentation reactions for accurate differentiation of Actinomyces and closely related species.

Actinomyces↗
PubMed1999

Molecular and genetic analyses of Actinomyces spp.

Members of the genus Actinomyces are predominant primary colonizers of the oral cavity and play an important role in initiating plaque development. These bacteria have evolved unique mechanisms that favor colonization and persistence in this micro-environment. The expression of cell-surface fimbriae is correlated with the ability of these bacteria to adhere to specific receptors on the tooth and mucosal surfaces, and to interact with other plaque bacteria. The elaboration of sialidase is thought to enhance fimbriae-mediated adherence by unmasking the fimbrial receptors on mammalian cells. The presence of certain cell-associated or extracellular enzymes, including those involved in sucrose or urea metabolism, may provide the means for these bacteria to thrive under conditions when other growth nutrients are not available. Moreover, these enzyme activities may influence the distribution of other plaque bacteria and promote selection for Actinomyces spp. in certain ecological niches. The recent development of a genetic transfer system for Actinomyces spp. has allowed for studies the results of which demonstrate the existence of multiple genes involved in fimbriae synthesis and function, and facilitated the construction of allelic replacement mutants at each gene locus. Analyses of these mutants have revealed a direct correlation between the synthesis of assembled fimbriae and the observed adherence properties. Further genetic analysis of the various enzyme activities detected from strains of Actinomyces should allow for an assessment of the role of these components in microbial ecology, and their contribution to the overall success of Actinomyces spp. as a primary colonizer and a key player in oral health and disease.

Actinomyces↗
PubMed1992

Eubacterium nodatum mimics Actinomyces in intrauterine device-associated infections and other settings within the female genital tract.

Eubacterium nodatum is an obligately anaerobic, gram-positive, branching rod that markedly resembles Actinomyces, particularly Actinomyces israelii, in its cellular and colonial characteristics. Its isolation from the female genital tract was examined for a study period in which use of intrauterine contraceptive devices (IUDs) was common, and additional characteristics of the organism were investigated. Fifteen genital isolates of E nodatum were all associated with the presence of a foreign body, usually an IUD (12 patients). Six of these 12 patients had presented with clinically severe pelvic inflammatory disease. The remaining six had signs and symptoms related to IUD use and/or had a report of probable Actinomyces (five patients) by a Papanicolaou smear, demonstrating that E nodatum can be mistaken for Actinomyces in a Papanicolaou-stained smear. The three other patients had different types of foreign bodies. The frequency of isolation from cultures associated with IUD use during the study period was five (6.4%) of 78 for Actinomyces versus the 12 (15.4%) of 78 for E nodatum. In vitro-prepared E nodatum was not demonstrated to cross-react with A israelii or A naeslundii antisera. Both E nodatum and A israelii were shown to adhere in vitro to an inanimate object, indicating their propensities to colonize a foreign body. The present data, with the previous reports of isolation of E nodatum from cases of lumpy jaw and severe periodontitis, suggest that it is an opportunistic pathogen very much like A israelii.

Actinomyces↗
PubMedDate not supplied

Actinomyces in cervical smears of women using intrauterine contraceptive devices.

Cervical smears from 1,784 women who attended the family planning clinics of the Institute for Research in Reproduction were examined for the presence of Actinomyces-like organisms. Among 815 intrauterine contraceptive device (IUD) users, the repeat smears from 57 women were positive for Actinomyces-like organisms, giving a prevalence rate of 6.99%. Immunofluorescent staining using specific antisera confirmed the presence of A. israelii in all 57 women. Forty IUD users whose smears were positive for Actinomyces-like organisms underwent bacteriologic culture studies; A. israelii was isolated in 23 of these cases. The clinical findings at the time of smear collection in the 57 IUD users were within normal limits. The initial cervical smears of all IUD users and both the initial and repeat smears of all nonusers were negative for Actinomyces-like organisms. The data indicate that prolonged use (greater than 2 years) of an inert or copper intrauterine device promotes the overgrowth of Actinomyces in the vagina and that this can be detected by routine cervical cytology.

Actinomyces↗
PubMed1993

[Actinomyces-like organisms infection in intrauterine devices wearers].

The prevalence of actinomyces-like organisms in cervicovaginal smears of 2,327 Chinese women, including 1,279 intrauterine devices (IUD) wearers and 1,048 non wearers, was investigated. Cervical smears were stained by the Papanicolaou method for the microscopic examination of actinomyces-like organisms. The relationship between actinomyces-like organisms infection and occupations, age, duration of IUD wearing and clinical symptoms were analysis. The result showed that the overall detection rate of actinomyces-like organisms in 2,327 women was 0.69%. The detection rates in IUD wearers and non-wearers were 1.1% and 0.2%, respectively, which were significantly different (P < 0.01). The rate of actinomyces-like organisms infection was significantly higher in women wearing IUD for more than seven years. Whereas the occupation or age of women did not affect the detection rate significantly.

Actinomyces↗
PubMed2001

[Ovarian abscess due to Actinomyces sp. in absence of an intrauterine contraceptive device].

The disease caused by Actinomyces spp. is often of difficult diagnosis. Actinomyces spp. are anaerobic or microaerophilic non-spore-forming gram-positive rods that may reach, occasionally, the normal female genital tract. IUD and pessaries facilitate the access of the microorganisms to the pelvis. We report an unusual case of ovarian infection by Actinomyces sp. in a 41 year-old female without IUD, admitted at the Institute in November 1998, with persistent fever. She had had an early menopause 3 years before, and had received hormonal replacement therapy. Usual and unusual infections were discarded by microbiological and serologic studies. Abdominal ultrasonography showed a slight left pyelocalycial dilatation and a simple cyst in the left ovary; heart ultrasonography was normal. Gynecological examination showed an enlarged uterus, similar to an 8 week pregnancy, painless, and fixed anexial masses. The transvaginal ultrasonography showed uterine myomas, one of them of 42 mm in the isthmus region, large ovaries, cystic, with acoustic shadows, and the left one with a septum. The preoperative diagnosis was infected bilateral cystic teratoma. The procedure was an exploratory laparotomy, followed by a bilateral salpingo-oophorectomy. The specimen studies showed an endometrioma with calcium deposits in the wall of the right ovary, and an abscess in the left ovary, also with calcification of the wall. The sample from the left abscess developed Actinomyces sp. After surgery, and treatment with penicillin, the fever disappeared. It is important to remark that the ovarian infection by Actinomyces sp. can also occur in patients without an IUD or a pessary; it might cause anexial images that can be interpreted as a tumour, inducing to erroneous diagnosis and treatment.

Abscess↗
PubMed1996

Detection of Actinomyces species using nonradioactive riboprobes coupled with polymerase chain reaction.

We have been focusing our attention on the detection and identification of oral bacteria which are frequently associated with periodontal disease. In previous studies, Actinomyces species-specific riboprobes were generated and used to identify this microorganism. However, problems lie in the low sensitivity of this method. We have developed a novel system for the detection of Actinomyces species using nonradioactive riboprobes coupled with polymerase chain reaction (PCR) in this study. This system employs two procedures; initially, DNA fragments specific for the target microorganism are amplified by PCR, and these specific fragments are further hybridized with nonradioactive riboprobes. PCR analysis using chromosomal DNA isolated from Actinomyces species including laboratory strains, clinical isolates, and Actinomyces naeslundii (ATCC 12104) indicated the presence of the predicted common 756-bp fragment, a portion of the sialidase gene. These amplified DNA fragments were effectively visualized by hybridization with the digoxigenin-labeled riboprobes corresponding to the internal region of the amplified sialidase gene. With this system, approximately three orders of magnitude less chromosomal DNA was sufficient for the detection of specific microorganisms compared to the conventional riboprobe systems.

Actinomyces↗
PubMed1964

IDENTIFICATION OF SPECIES OF ACTINOMYCES.

Georg, Lucille K. (Communicable Disease Center, Atlanta, Ga.), Gordon W. Robertstad, and Sherry A. Brinkman. Identification of species of Actinomyces. J. Bacteriol. 88:477-490. 1964.-Four unusual isolates of Actinomyces species were compared with six control strains of well-identified Actinomyces species. Their oxygen requirements and their morphological and biochemical characteristics were determined. Final identifications were confirmed by cell-wall analyses for amino acid and carbohydrate composition and by agar-gel techniques. Two strains, A-13-R and A-13-S, isolated from the same cow head were shown to represent rough and smooth variants of A. bovis. The strains were not only morphologically distinct, but had different biochemical reactions and antigenic makeup. The two other strains, X407 and X573, isolated from human pleural fluid and a lung abscess, respectively, were shown to represent a new Actinomyces species.

Actinomyces↗
PubMed1993

Characterization of Actinomyces with genomic DNA fingerprints and rRNA gene probes.

Cellular DNA from 25 Actinomyces naeslundii and Actinomyces viscosus strains belonging to the 7 taxonomic clusters of Fillery et al. (1978) and several unclustered strains was obtained by enzymatic and N-lauroylsarcosine/guanidine isothiocyanate treatment of whole cells, followed by extraction of the nucleic acid. The DNA samples were digested with restriction endonucleases BamHI or PvuII, and agarose gel electrophoresis was used to obtain DNA fingerprints. The DNA fragments were subjected to Southern blot hybridization with a digoxigenin-labeled cDNA probe transcribed from Escherichia coli 16S and 23S rRNA. The patterns of bands from genomic (DNA fingerprints) and rDNA fingerprints (ribotypes) were used for comparison between the taxonomic cluster strains and strains within clusters. Representative strains from each taxonomic cluster provided different BamHI DNA fingerprints and ribotype patterns with 3 to 9 distinct bands. Some strains within a cluster showed identical ribotype patterns with both endonucleases (A. naeslundii B120 and A. naeslundii B102 from cluster 3), while others showed the same pattern with BamHI but a different pattern with PvuII (A. naeslundii ATCC 12104 and 398A from cluster 5). A viscosus ATCC 15987 (cluster 7) and its parent strain T6 yielded identical fingerprint and ribotype patterns. The genomic diversity revealed by DNA fingerprinting and ribotyping demonstrates that these techniques, which do not require phenotypic expression, are suited for study of the oral ecology of the Actinomyces, and for epidemiological tracking of specific Actinomyces strains associated with caries lesions and sites of periodontal destruction.

Actinomyces↗
PubMed1984

A simple method for extracting human lymphocyte stimulants from human dental plaque bacteria of the genus Actinomyces.

The effect of acid concentration on the hot-acid extraction of antigens from Actinomyces viscosus that stimulate human peripheral blood lymphocytes in vitro was tested. The optimum pH for release of these antigens in a soluble low molecular-weight form was pH 2.3. Preliminary purification on Sepharose 4B demonstrated that most of the lympho-stimulatory material (about 90 per cent) had a mol. wt of about 100,000. This partially-purified antigenic material was mainly protein. The pH 2.3 hot-acid extraction was also suitable for extracting antigens that stimulate cellular immune responses from three strains of Actinomyces naeslundii and 1 strain of Actinomyces israelii, but did not release lympho-stimulatory material from Streptococcus sanguis which is a poor human peripheral-blood lymphocyte-stimulant and was used to demonstrate that the hot-acid extraction is not simply extracting a mitogenic macromolecule common to all bacteria. As good yields of soluble, biologically-active antigens were obtained from all of the Actinomyces, the procedure described will facilitate the purification and characterization of these antigens.

Actinomyces↗
PubMed1990

Indirect immunofluorescence microscopy for the identification of Actinomyces sp. in endodontic disease.

Indirect immunofluorescence microscopy was used to determine the presence of select Actinomyces sp. in a clinical survey of teeth with endodontic disease. Thirty canal samples were tested for the presence of Actinomyces sp.: A. israelii, A. odontolyticus, A. viscosus serotype I, and A. viscosus serotype II. Actinomyces sp. were identified in 18 (60%) samples. A. israelii was most frequently identified with immunofluorescence in 16 (53%) cases examined and was the test organism most often associated with endodontic disease within the restrictions of this study. Positive and negative controls were appropriate to support findings. Indirect immunofluorescence microscopy can be used for the clinical identification of Actinomyces sp. in endodontic disease without the necessity of performing a parallel culture study.

Actinomyces↗
PubMed1999

Molecular approaches to the differentiation of Actinomyces species.

The definition of the genus Actinomyces relies heavily on traditional methods of taxonomy. This study sought to develop molecular tools for the identification of strains of Actinomyces israelii and Actinomyces gerencseriae. Oligonucleotide probes were designed and one of these successfully differentiated. A. gerencseriae from ten strains of A. israelii and three other Actinomyces species by DNA:DNA hybridization. However, probes based on known 16S rRNA sequences failed to hybridize to all the strains previously identified as A. israelii. Using the PCR technique, a region encoding a portion of the 16S rRNA was amplified from genomic DNA. The results showed that A. israelii can be divided into three different groups based on comparison of the amplified DNA sequences. This information should allow the development of probes that are specific for these newly identified groups of strains within the species A. israelii.

Actinomyces↗
PubMed1995

Description of human-derived Centers for Disease Control coryneform group 2 bacteria as Actinomyces bernardiae sp. nov.

Biochemical, chemotaxonomic, and molecular methods were used to establish the precise taxonomic position of the Centers for Disease Control (CDC) coryneform group 2 bacteria. The results of a comparative 16S rRNA sequence analysis demonstrated that the CDC coryneform group 2 bacteria constitute a distinct species within the genus Actinomyces. Actinomyces pyogenes was found to be the closest genealogical relative of the CDC coryneform group 2 bacteria, although these taxa were readily distinguished from each other and other Actinomyces spp. by using phenotypic criteria. On the basis of our findings we propose the name Actinomyces bernardiae sp. nov. for the CDC coryneform group 2 bacteria. The type strain is DSM 9152 (CCUG 33419).

Actinomyces↗
PubMed1997

Actinomyces europaeus sp. nov., isolated from human clinical specimens.

Ten strains of a hitherto undescribed catalase-negative, facultatively anaerobic, coryneform bacterium were isolated or collected by workers at three European clinical bacteriology laboratories or reference centers. These strains were isolated from humans, and most came from abscess material. Biochemical and chemotaxonomic characterization revealed that the strains belonged to the genus Actinomyces. The phenotypic features of the 10 strains were incompatible with the descriptions of the previously established Actinomyces species. A comparative 16S rRNA gene sequence analysis demonstrated that the previously undescribed strains constitute a new line in the genus Actinomyces. The name Actinomyces europaeus sp. nov. is proposed for these clinical isolates. The type strain is CCUG 32789A.

Actinomyces↗