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PubMed2001

Actinomyces marimammalium sp. nov., from marine mammals.

Three strains of a previously undescribed Actinomyces-like bacterium were isolated from samples taken from two dead seals and a porpoise. Biochemical testing and PAGE analysis of whole-cell proteins indicated the strains were phenotypically similar to each other but different from previously described Actinomyces and Arcanobacterium species. Comparative 16S rRNA gene sequencing studies showed the organisms from marine animals were genetically closely related and represent a hitherto unknown subline within the genus Actinomyces (sequence divergence values > 6% with recognized species). Based on phylogenetic and phenotypic evidence it is proposed that the unknown bacterium from the seals and a porpoise should be classified as Actinomyces marimammalium sp. nov. The type strain is CCUG 41710T.

Actinomyces↗
PubMed1975

Numerical taxonomy and laboratory identification of Actinomyces and Arachnia and some related bacteria.

A numerical taxonomic study was made on 49 facultative anaerobic Gram-positive filamentous and/or diphtheroidal organisms isolated from dental plaques, carious dentin and faeces, together with 63 reference strains belonging to the genera Actinomyces, Arachnia, Bifidobacterium, Actinobacterium, Propionibacterium, Eubacterium and Lactobacillus. They were examined for 90 unit characters covering a wide range of tests and properties. The data were subjected to computer analysis in which the simple matching coefficient (SSM) and the similarity index (SJ) were calculated, and the results of single linkage techniques and an unweighted average linkage cluster analysis technique were compared. The strains fell into six major groups (phena). The Actinomyces strains were recovered in two phena; the first contained Actinomyces israelii and the other facultative anaerobic Actinomyces, including subclusters equal to taxospecies of A. odontolyticus and A. viscosus/A. naeslundii, while the other phenon corresponded to the genera Arachnia, Actinobacterium, Bifidobacterium and Propionibacterium. The groups of Arachnia and Actinobacterium each contained one species, representing taxospecies of Arachnia propionica and Actinobacterium meyerii. Taxonomic criteria, both constant and discriminative, were selected to form a diagnostic table useful for laboratory identification of this group of organisms. Immunofluorescence supported the numerical data.

Actinomyces↗
PubMed2003

Actinomyces nasicola sp. nov., isolated from a human nose.

A previously undescribed facultatively anaerobic, catalase-negative, Actinomyces-like bacterium was isolated from the nose of a human. On the basis of its cellular morphology and the results of biochemical testing, the micro-organism was tentatively identified as a member of the genus Actinomyces, but it did not correspond to any currently recognized species. Comparative 16S rRNA gene sequencing studies showed the bacterium to be a hitherto unknown subline within the genus Actinomyces, displaying sequence divergence values of more than 6 % with respect to recognized species of the genus. On the basis of biochemical, molecular chemical and molecular phylogenetic evidence, it is proposed that the unknown organism, strain R2014(T) (=CCUG 46092(T)=CIP 107668(T)), be classified as the type strain of a novel species, Actinomyces nasicola sp. nov.

Actinomyces↗
PubMed2005

Actinomyces dentalis sp. nov., from a human dental abscess.

A previously undescribed filamentous, beaded, Gram-positive, rod-shaped bacterium was isolated from pus of a human dental abscess. Based on its cellular morphology and the results of biochemical testing the organism was tentatively identified as a member of the genus Actinomyces, but it did not correspond to any currently recognized species of this genus. Comparative 16S rRNA gene sequencing studies showed the bacterium represents a distinct subline within the genus Actinomyces, clustering within a group of species that includes Actinomyces bovis, the type species of the genus. Sequence divergence values of >8 % with other recognized species within this phylogenetic group clearly demonstrated that the organism represents a hitherto unknown species. Based on biochemical and molecular phylogenetic evidence, it is proposed that the unidentified organism recovered from a dental abscess be classified as a novel species, Actinomyces dentalis sp. nov. The type strain is R18165T (=CCUG 48064T=CIP 108337T).

Abscess↗
PubMed2006

Actinomyces ruminicola sp. nov., isolated from cattle rumen.

Two obligate anaerobic bacterial strains, B71(T) and D471, were isolated from cattle rumen. The novel strains were Gram-positive and rod-shaped. The strains hydrolysed xylan and starch, fermented some mono-, di- and oligosaccharides and produced formic, acetic and lactic acids as end products from glucose. Growth of the isolates was observed at 20-55 degrees Celsius and pH 6.5-9.0. The DNA G+C contents of strains B71(T) and D471 were 68.06 and 68.26 mol%, respectively. Although the two novel strains met the genus description for Actinomyces, some phenotypic characteristics, such as optimum growth temperature, requirement for O(2) and the end products of fermentation, distinguished them from previously described members of the genus. Phylogenetic analysis based on 16S rRNA gene sequences demonstrated that the novel strains belonged to the genus Actinomyces (88.3-93.6 % sequence similarity) and formed a distinct line within the clade containing Actinomyces bovis. On the basis of these results, a novel species, Actinomyces ruminicola sp. nov., is proposed. The type strain is B71(T) (=JCM 13352(T)=CGMCC 1.5030(T)).

Actinomyces↗
PubMed2004

Biofilm growth of Lactobacillus species is promoted by Actinomyces species and Streptococcus mutans.

The ability of oral bacteria to integrate within a biofilm is pivotal to their survival. A dependence on the amount of biofilm growth by noncoaggregating Lactobacillus rhamnosus and Lactobacillus plantarum on coculture with Actinomyces naeslundii, Actinomyces gerencseriae, Streptococcus mutans and Veillonella parvula was investigated using an artificial-mouth culture system. Biofilm formation by the lactobacilli in mono-culture was poor. In coculture with Actinomyces species the amount of L. rhamnosus increased 7-20 times and L. plantarum 4-7 times compared to its mono-culture biofilm. S. mutans also promoted substantial biofilm growth of lactobacilli but V. parvula had no effect. We conclude that these Actinomyces species promoted growth of key Lactobacillus species in a biofilm, as did S. mutans to a smaller extent, and that the ability of individual bacteria to form mono-culture biofilms is not necessarily an indicator of their survival and pathogenic potential in a complex multispecies biofilm community.

Actinomyces↗
PubMed1997

Incidence of tonsillar lesions caused by Tonsillophilus suis and Actinomyces sp infection in swine.

The tonsils of ten fattening pigs were compared with those of ten breeding sows to determine the relative incidence of Tonsillophilus suis and Actinomyces sp lesions. Macroscopic observation revealed mildly focal upheavals on the tonsillar mucosal surfaces of two of the breeding sows. In tonsillar slices from both pig groups, tiny nodules containing sulfur granules were found. Histopathologically, the T. suis and Actinomyces sp lesions were noted as tonsillar crypt abscesses in both pig groups, and granulomas due to T. suis were seen in the breeding sows. T. suis showed larger 'club-shaped' structures than Actinomyces sp, characterized as clubs showing a broom-like structure with degenerated central thalli. Breeding sows are known to have a higher incidence of tonsillar T. suis lesions than fattening pigs, and in this study, those fattening pigs showing greater propensity to infection by Actinomyces sp also showed a mixed infection with T. suis that produced the tonsillar crypt abscesses. In addition, it is known that in breeding sows, the T. suis lesion develops from a crypt abscess into a granuloma.

Actinomyces↗
PubMed1985

Immunocytochemical demonstration of Actinomyces species and Arachnia propionica in periapical infections.

Immunocytochemical methods were used for the demonstration of Actinomyces israelii, Actinomyces naeslundii and Arachnia propionica in bacterial colonies found in 7 routine biopsies from periapical inflammatory lesions. All 3 species were found in one specimen, both A. israelii and A. propionica in 3 specimens, and one of each species in the remaining 3 biopsies. Specificity controls by enzyme immunoassay showed that antiserum to A. israelii reacted also with A. odontolyticus, and that to A. naeslundii with A. viscosus, while antiserum to A. propionica did not show any cross-reactions with Actinomyces species. The results indicate that immunocytochemical methods can be used for the diagnosis of periapical actinomycosis at the species level. Actinomyces and Arachnia species seem to have an important role in the pathogenesis of complicated periapical infections.

Actinomyces↗
PubMed1971

Interaction of Actinomyces organisms with cationic polypeptides. I. Histochemical studies of infected human and animal tissues.

Histochemical techniques were used to study the nature of acidophilic hyaline clubs arranged radially at the peripheries of Actinomyces colonies in infected lung tissues of two persons. Concentrations of arginine-rich polypeptides were demonstrated in the acidophilic areas and in the cytoplasm of granulocytic leukocytes surrounding the colonies. Exposure of Actinomyces organisms to strongly cationic polypeptides (protamine, histone) in vitro killed the organisms and caused them to develop acidophilic staining. Weakly cationic proteins, ribonuclease, and hemoglobin produced no such effects. No acidophilic component could be detected in fresh broth-grown organisms themselves. Viable and nonviable colonies of the test strain lacking hyaline clubs were injected beneath the skin of guinea pigs. Agrinine-rich cationic polypeptides were evident in the cytoplasm of surrounding leukocytes and permeating the microbial colonies. In light of current evidence pertaining to leukocyte lysosomes and capsule production by Actinomyces and related organisms, the acidophilic hyaline clubs observed in human tissues appear to be a combination of a capsular component of the actinomycete and a cationic polypeptide component of host leukocytes. Organisms deeper in the human tissue colonies retained their normal basophilic reaction, suggesting a protective role for the peripheral hyaline club matrix. The acidophilic club complexes serve to indicate the reaction of cationic polypeptides in response of the human host to infecting Actinomyces organisms. These observations also support a broader concept that antimicrobial polypeptides of leukocyte lysosomes are an important factor in response of both the human and animal host to infecting bacteria.

Abscess↗
PubMed1988

Human salivary acidic proline-rich proteins and statherin promote the attachment of Actinomyces viscosus LY7 to apatitic surfaces.

Actinomyces viscosus LY7 cells adsorbed in high numbers to experimental pellicles formed on hydroxyapatite (HA) from human parotid or submandibular saliva but not to pellicles prepared from human plasma or serum. To determine the nature of the salivary components responsible for promoting adhesion, pellicles were prepared from fractions of submandibular and parotid saliva obtained by chromatography on Trisacryl GF 2000 columns. Adsorption of LY7 cells was promoted by two groups of fractions. Each group was rechromatographed on DEAE-agarose. Fractions which promoted adsorption of LY7 cells were found by polyacrylamide gel electrophoresis to contain the acidic proline-rich proteins (PRPs) and statherin. Pellicles prepared from 12-micrograms/ml solutions of pure PRP-1, PRP-2, or parotid isoelectric focusing (PIF-slow) variant promoted maximal adsorption of A. viscosus LY7 cells. Somewhat higher concentrations of PRP-3 and PRP-4 were required for maximal adsorption, indicating that the 44-residue carboxy-terminal segment of PRP-1, PRP-2, and PIF-slow enhances LY7 binding but is not essential. Much higher concentrations of statherin were required to promote LY7 adsorption. Adsorption of LY7 cells to pellicles prepared from PRP-1 was not affected over the range of pH 5 to 8. Adsorption was also not inhibited by 50 mM lactose, which is consistent with the notion that type 1 fimbriae, rather than type 2 fimbriae, were responsible. A. viscosus T14, Actinomyces odontolyticus ATCC 17982, and Actinomyces israelii 12597 also adsorbed to PRP-1 pellicles, whereas Actinomyces naeslundii ATCC 12104 did not. Although A. viscosus cells bind strongly to adsorbed PRP-1, the presence of PRP-1 or PRP-3 in solution did not inhibit adhesion. Similarly, [3H]PRP-1 did not bind to LY7 cells, nor was it degraded when incubated with the organism. However, LY7 cells adsorbed to [3H]PRP-1 pellicles. These data suggest that hidden molecular segments of PRP become exposed when the protein adsorbs to HA; these segments then react with adhesins of LY7 cells. The apparent ability of A. viscosus cells to recognize segments of PRPs which are exposed only in surface-adsorbed molecules provides a novel mechanism which enables the organism to attach to teeth when suspended in salivary secretions.

Actinomyces↗
PubMed1998

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.

Actinomyces↗
PubMed2000

Identification of polymorphonuclear leukocyte and HL-60 cell receptors for adhesins of Streptococcus gordonii and Actinomyces naeslundii.

Interactions of oral streptococci and actinomyces with polymorphonuclear leukocytes (PMNs), mediated by sialic acid- and Gal/GalNAc-reactive adhesins, respectively, result in activation of the PMNs and thereby may contribute to the initiation of oral inflammation. Sialidase treatment of PMNs or HL-60 cells abolished adhesion of Streptococcus gordonii but was required for adhesion of Actinomyces naeslundii. The same effects of sialidase were noted for adhesion of these bacteria to a major 150-kDa surface glycoprotein of either PMNs or undifferentiated HL-60 cells and to a 130-kDa surface glycoprotein of differentiated HL-60 cells. These glycoproteins were both identified as leukosialin (CD43) by immunoprecipitation with a specific monoclonal antibody (MAb). Adhesion of streptococci and actinomyces to a 200-kDa minor PMN surface glycoprotein was also detected by bacterial overlay of untreated and sialidase-treated nitrocellulose transfers, respectively. This glycoprotein was identified as leukocyte common antigen (CD45) by immunoprecipitation with a specific MAb. CD43 and CD45 both possess extracellular mucinlike domains in addition to intracellular domains that are implicated in signal transduction. Consequently, the interactions of streptococci and actinomyces with the mucinlike domains of these mammalian cell surface glycoproteins result not only in adhesion but, in addition, may represent the initial step in PMN activation by these bacteria.

Actinomyces↗
PubMed2003

Coaggregation-mediated interactions of streptococci and actinomyces detected in initial human dental plaque.

Streptococci and actinomyces that initiate colonization of the tooth surface frequently coaggregate with each other as well as with other oral bacteria. These observations have led to the hypothesis that interbacterial adhesion influences spatiotemporal development of plaque. To assess the role of such interactions in oral biofilm formation in vivo, antibodies directed against bacterial surface components that mediate coaggregation interactions were used as direct immunofluorescent probes in conjunction with laser confocal microscopy to determine the distribution and spatial arrangement of bacteria within intact human plaque formed on retrievable enamel chips. In intrageneric coaggregation, streptococci such as Streptococcus gordonii DL1 recognize receptor polysaccharides (RPS) borne on other streptococci such as Streptococcus oralis 34. To define potentially interactive subsets of streptococci in the developing plaque, an antibody against RPS (anti-RPS) was used together with an antibody against S. gordonii DL1 (anti-DL1). These antibodies reacted primarily with single cells in 4-h-old plaque and with mixed-species microcolonies in 8-h-old plaque. Anti-RPS-reactive bacteria frequently formed microcolonies with anti-DL1-reactive bacteria and with other bacteria distinguished by general nucleic acid stains. In intergeneric coaggregation between streptococci and actinomyces, type 2 fimbriae of actinomyces recognize RPS on the streptococci. Cells reactive with antibody against type 2 fimbriae of Actinomyces naeslundii T14V (anti-type-2) were much less frequent than either subset of streptococci. However, bacteria reactive with anti-type-2 were seen in intimate association with anti-RPS-reactive cells. These results are the first direct demonstration of coaggregation-mediated interactions during initial plaque accumulation in vivo. Further, these results demonstrate the spatiotemporal development and prevalence of mixed-species communities in early dental plaque.

Actinomyces↗
PubMed1967

Isolation and characterization of Actinomyces propionicus.

Three cultures of Actinomyces have been identified as Actinomyces propionicus. Two of these strains are recent isolates, one, 427, from a case of cervico-facial actinomycosis, and one, 439, from a case of lacrimal canaliculitis. The third strain, 346, was described by F. Lentze as A. israelii serological type II. These three strains were compared with the type strain of A. propionicus ATTC 14157 and with known strains of five other Actinomyces species. Morphologically and biochemically the three new cultures of A. propionicus were identical with the type strain but closely resembled A. israelii. In serological tests making use of fluorescent antibody, all four A. propionicus strains gave negative results with antisera for A. israelii, A. bovis, A. naeslundii, and A. eriksonii, but gave positive results with antisera for A. propionicus 14157 and strain 346. The A. propionicus antisera did not stain other Actinomyces species. A. propionicus contains diaminopimelic acid (DAP) in its cell wall and produces propionic acid from glucose. All three new isolates were shown to contain DAP and to produce propionic acid. By use of the presence of DAP in the cell wall and serological tests as the differential criteria, the three cultures described in the report were specifically identified as A. propionicus.

Actinomyces↗
PubMed1967

Comparative cell wall analyses of morphological forms within the genus Actinomyces.

Comparative cell wall analyses were made of mycelial and smooth forms of Actinomyces bovis and A. israelii to determine the changes which occur in the cell wall composition concurrent with a change in morphology, and to evaluate cell wall analyses as a criterion for taxonomic identification within the genus Actinomyces. Cell walls of the spider forms of A. boyis had little or no aspartic acid and a high hexosamine concentration; cell walls of the smooth forms had a high aspartic acid content and low concentrations of hexosamine. Both forms had large amounts of glutamic acid, alanine, and lysine, as previously reported. A strain of Actinomyces, previously identified as A. naeslundii on the basis of morphology and aerobic growth characteristics, was found to have the basic cell wall composition of A. israelii. When transferred from the Actinomyces maintenance broth to a thioglycolate broth, the cells of this strain passed from a mycelial form through a transient filamentous morphology to become diphtheroidal with continued incubation. Concomitantly, the concentrations of glutamic acid relative to alanine decreased, and the hexosamine content increased. Variation in morphology within the species A. israelii and A. bovis could not be related to any mutual chemical change of their cell walls.

Actinomyces↗
PubMed2003

Oral Actinomyces isolates forming red colonies on brain heart blood agar can bee unambiguously classified as A odontolyticus by macroscopic examination.

The accurate classification of oral Actinomyces isolates as one species is difficult. Out of 18 Actinomyces isolates forming red colonies on brain heart blood agar, 12 could be straightforwardly assigned as Actinomyces odontolyticus by biochemical, morphological, and chemotaxonomic characteristics. For the remaining six isolates, the results of the different identification methods were inconsistent. By sequencing a 16S ribosomal DNA fragment by a rapid mass spectrometric method, all isolates could be identified unambiguously as A. odontolyticus. This result proves the importance of red colony pigmentation on brain heart blood agar together with the characteristic cell morphology for unequivocal assignment of oral Actinomyces isolates to the species A. odontolyticus.

Actinomyces↗
PubMed2001

The importance of the removal of the intrauterine device in genital colonization by actinomyces.

OBJECTIVE: To determine whether, in addition to treatment with antibiotics, it is necessary to remove the intrauterine device (IUD) to eliminate genital colonization by Actinomyces. METHODS: A randomized clinical trial was carried out. Patients were divided into two groups. The intervention group did not have their IUDs removed, while the control group did. Both groups were treated with trimethoprim and sulfamethoxazole. A total of 43 patients were included. RESULTS: The patients from the intervention group and the control group proved to be comparable. The post-intervention cytology smear tested negative for Actinomyces in 100% of the patients whose IUD had been removed and in 66.7% of those whose IUD had not been removed (p = 0.005). The probability that colonization by Actinomyces will continue if the IUD is not removed is greater the longer the patient has been exposed to the IUD. After 24 months, relative risk (RR) = 2, after 36 months RR = 2.16 and after 48 months RR = 2.66. CONCLUSIONS: The removal of the IUD has been effective in genital colonization by Actinomyces. The protective effect exerted by the removal of the IUD was found to be greater in proportion to the length of time the patient had used it.

Actinomyces↗
PubMed1999

The predominant Actinomyces spp. isolated from infected dentin of active root caries lesions.

Actinomyces are Gram-positive pleomorphic rods (GPPR) which form a large proportion of the oral microflora of all mammals. They have been implicated in root caries, although their role in dental caries initiation and progression is not well-understood. Many studies have focused on Actinomyces naeslundii, but few reports have documented other members of the GPPR. Therefore, we investigated the GPPRs isolated from infected dentin of active root caries lesions (n = 9) to determine which species were the most frequently isolated. The GPPR were isolated under both aerobic and anaerobic conditions and identified by biochemical and physiological tests to the species level according to the new taxonomy. Of 654 GPPR isolates investigated, 607 were identified as belonging to the genus Actinomyces. Of these, 242 were identified as A. israelii, 225 as A. gerencseriae, 109 as A. naeslundii, 15 as A. odontolyticus, and 13 as A. georgiae. Individual strains of A. israelii (n = 56) and A. gerencseriae (n = 46) were also investigated at the DNA level by means of Repetitive Extragenic Palindromic polymerase chain-reactions (REP-PCR) for the study of clonal diversity. Although only a small number of isolates was investigated, REP-PCR showed that the genotypes of both A. gerencseriae and A. israelii populations were heterogeneous within individual root caries lesions. A. gerencseriae and A. israelii strains from the same lesions did not share the same REP-PCR patterns, showing the robustness of the identification scheme. A significantly greater proportion of A. gerencseriae was isolated from the aerobic plates (p < 0.05), while the proportion of A. israelii was significantly (p < 0.05) greater from anaerobic plates. The role of individual Actinomyces spp. in the root caries process remains unclear, since various populations of GPPRs were isolated from individual active root caries lesions.

Actinomyces↗