Actinomyces georgiae sp. nov., Actinomyces gerencseriae sp. nov., designation of two genospecies of Actinomyces naeslundii, and inclusion of A. naeslundii serotypes II and III and Actinomyces viscosus serotype II in A. naeslundii genospecies 2

DNAs of type strains and representative members of Actinomyces groups from the human periodontal flora and from other habitats were compared by using the S1 nuclease procedure to determine their genetic relatedness. One rather common group from the human periodontal flora, previously called "Actinomyces D08," is phenotypically distinct from, and genetically unrelated to, previously described species. We propose the name of Actinomyces georgiae for this organism; the type strain is strain ATCC 49285. Another common group from the human periodontal flora is Actinomyces israelii serotype II, which was found genetically distinct from the type strain of A. israelii (serotype I) and from other previously described species of Actinomyces. We propose the name Actinomyces gerencseriae for this organism; the type strain is strain ATCC 23860. A. naeslundii serotype I strains were distinct from the other strains studied. A separate genospecies which included strains of A. naeslundii serotypes II and III and A. viscosus serotype II was delineated. Strains of Actinomyces serotype WVA 963 constitute an additional distinct genospecies. Because there are no reliable phenotypic tests, other than serological analyses, to differentiate Actinomyces serotype WVA 963 and the two genospecies of A. naeslundii, no taxonomic changes are proposed for these three genospecies.     

Reclassification of Corynebacterium pyogenes (Glage) in the genus Actinomyces, as Actinomyces pyogenes comb.nov

Corynebacterium pyogenes (Glage) differs to such an extent from the type species of Corynebacterium, Corynebacterium diphtheriae (Lehmann and Neumann), that it cannot be retained in this genus. Numerical phenetic and chemical data indicate a close relationship between Corynebacterium pyogenes and the species Actinomyces bovis (Harz). It is proposed that Corynebacterium pyogenes be reclassified in the genus Actinomyces, as Actinomyces pyogenes (Glage) comb.nov.     

Red light kills bacteria via photodynamic action.

With the increase in the number of antibiotic resistant strains of microorganism, the search for alternative treatments of microbial infections becomes all the more important. We report a novel method for bacterial inactivation based on the optical excitation of the naturally occurring (endogenous) photosensitzing porphyrins by red light. In particular, the pathogenic Gram-positive porphyrin producing ATCC strains Propionibacterium acnes, Actinomyces odontolyticus and Porphyromonas gingivalis were investigated. Sensitive autofluorescence spectroscopy revealed that these bacteria naturally synthezise the fluorescent photosensitizer protoporphyrin IX. In addition, bacterial plaque samples of periodontitis patients were studied. Non-labeled fluorescent bacterial colonies were exposed to red light at 632.8 nm, 100 mW/cm2 light intensity and 360 J/cm2 energy density using a helium-neon laser. The survival rate after a single phototreatment with red light was found to be 0.58 +/- 0.09 in the case of Propionibacterium acnes, 0.30 +/- 0.04 in Actinomyces odontolyticus and 0.59 +/- 0.10 in Porphyrormonas gingivalis compared to non-exposed bacteria suspensions. No photoeffect was found for the bacterium Streptococcus mutans which exhibited no detectable porphyrin autofluorescence. Red-light exposed plaque samples of patients showed significant reduction of colony forming units by 50% as well as a pronounced photoeffect on the pigmented species Prevotella intermedia. Taken together, these results suggest the treatment with red light can be potentially employed as an therapeutic method to inactivate certain pathogenic strains of porphyrin producing bacteria without the use of external photosensitizers.     

Actinomyces denticolens Dent & Williams sp. nov: a new species from the dental plaque of cattle

D ent , V.E. & W illiams , R.A.D. 1984. Actinomyces denticolens Dent & Williams sp. nov: a new species from the dental plaque of cattle. Journal of Applied Bacteriology 56 , 183–192.
Six strains of actinomyces isolated from the dental plaque of cattle were assigned presumptively to the genus Actinomyces on the basis of Gram reaction, cellular and colony morphology and acid end-products of metabolism. This assignment was confirmed by the peptidoglycan composition which is shared with Actinomyces species from dental plaque. These cattle strains formed a homogeneous group on the basis of cell wall carbohydrate components, DNA base composition, polypep-tide molecular weight distribution and physiological reactions but could not be classified with any recognised species of Actinomyces . A new taxon Actinomyces denticolens is proposed for these strains.     

Phylogenetic evidence for the transfer of Eubacterium suis to the genus Actinomyces as Actinomyces suis comb. nov.

The 16S rRNA primary structures of Eubacterium suis DSM 20639T (T = type strain) and Bifidobacterium bifidum DSM 20456T were determined by sequencing in vitro amplified rDNA. Sequence comparisons indicated that B. bifidum is moderately related to representatives of the genera Actinomyces and Mobiluncus. The closest relative of E. suis is Actinomyces pyogenes. E. suis and A. pyogenes are more closely related phylogenetically to one another than to the other Actinomyces species that have been investigated by using comparative 16S rRNA analysis. Therefore, we propose that E. suis should be transferred to the genus Actinomyces as Actinomyces suis comb. nov.     

Actinomyces hongkongensis sp. nov. a novel Actinomyces species isolated from a patient with pelvic actinomycosis

A bacterium was isolated from the pus of a patient with pelvic actinomycosis. The cells were strictly anaerobic, straight, non-sporulating, Gram-positive rods. It grows on sheep blood agar as non-haemolytic, pinpoint colonies after 24 hours of incubation at 37 degrees C in anaerobic environment. It is non-motile and does not produce catalase. 16S ribosomal RNA (rRNA) gene sequencing showed that there were 6.6% difference between the 16S rRNA gene sequence of the bacterium that of Actinomyces marimammalium (GenBank Accession no. AJ276405), a new species described in 2001, isolated from two seals and a porpoise. For these reasons a new species, Actinomyces hongkongensis sp. nov., is proposed, for which HKU8(T) is the type strain. Further studies should be performed to ascertain the potential of this bacterium to become an important cause of actinomycosis.     

Coaggregation between Prevotella nigrescens and Prevotella intermedia with Actinomyces naeslundii strains

Abstract Using a visual coaggregation assay, 43% (6 of 14) of Prevotella nigrescens and 50% (4 of 8) of Prevotella intermedia strains coaggregated with Actinomyces naeslundii strains which represented the six Actinomyces coaggregation groups (A to F). For both species, coaggregation occurred most frequently with A. naeslundii strains from coaggregation groups C, D and E. No coaggregation was observed with Actinomyces israelii , Actinomyces odontolyticus or six oral Streptococcus species. Coaggregation was not inhibited by lactose, saliva or serum. Pretreatment of Prevotella strains with heat, SDS and proteinase K abolished coaggregation when the treated cells were added to untreated Actinomyces strains. The same pretreatment of the Actinomyces strains had no effect on their ability to coaggregate with untreated Prevotella strains. Pretreatment of all coaggregating P. nigrescens strains with trypsin abolished coaggregation, whereas the coaggregation ability of the P. intermedia and Actinomyces strains was resistant to trypsin pretreatment. Pretreatment of the strains of both Prevotella species and the Actinomyces with periodate abolished coaggregation in all cases. These results suggest that the Prevotella strains each possess a protein coaggregation adhesin, which for the P. intermedia strains is resistant to trypsin, that interacts with a non-protein receptor on the A. naeslundii strains.     

Assignment of Actinomyces pyogenes-like (CDC coryneform group E) bacteria to the genus Actinomyces as Actinomyces radingae sp. nov. and Actinomyces turicensis sp. nov.

In a previous study the authors reported the characterization of some facultatively anaerobic, Gram-positive, non-sporeforming rods which were found in mixed cultures from various infectious processes, including patients with otitis, empyema, perianal abscesses and decubitus ulcers. Phenotypically these organisms closely resembled Actinomyces pyogenes although their precise taxonomic position remained unknown. In the present investigation the authors have determined the 16S rRNA gene sequences of some representative strains of the Actinomyces pyogenes -like bacteria and report the results of a comparative sequence analysis. On the basis of the results of the present and earlier findings two new Actinomyces species, Actinomyces radingae sp. nov. and Actinomyces turicensis sp. nov. are proposed. The type strains are DSM 9169^T and DSM 9168^T, respectively.     

Coaggregation properties of human oral Veillonella spp.: relationship to colonization site and oral ecology.

The primary habitats of oral veillonellae are the tongue, dental plaque, and the buccal mucosa. Isolates were obtained from each habitat and tested for coaggregation with a battery of other oral bacterial strains. All 59 tongue isolates tested for coaggregation were Veillonella atypica or Veillonella dispar. All but one of them coaggregated with strains of Streptococcus salivarius, a predominant inhabitant of the tongue surface but not subgingival dental plaque. These tongue isolates were unable to coaggregate with most normal members of the subgingival flora such as Actinomyces viscosus, Actinomyces naeslundii, Actinomyces israelii, and Streptococcus sanguis. In contrast, 24 of 29 Veillonella isolates, of which 20 were Veillonella parvula from subgingival dental plaque samples, coaggregated strongly with the three species of Actinomyces, S. sanguis, and other bacteria usually present in subgingival plaque, but they did not coaggregate with S. salivarius. The majority of isolates from the buccal mucosa (42 of 55) has coaggregation properties like those from the tongue. These results indicate that the three human oral Veillonella species are distributed on oral surfaces that are also occupied by their coaggregation partners and thus provide strong evidence that coaggregation plays a critical role in the bacterial ecology of the oral cavity.     

Characterization of Actinomyces species isolated from failed dental implant fixtures

In the oral cavity, Actinomyces form a fundamental component of the indigenous microflora, being among initial colonizers in polymicrobial biofilms. However, some differences may exist between different species in terms of their attachment not only to teeth but also to biomaterials. In this study we investigated the distribution of Actinomyces in 33 dental implant fixtures explanted from 17 patients. The identification was based on comprehensive biochemical testing and gas-liquid chromatography and when needed, 16S rRNA sequencing. Actinomyces was the most prevalent bacterial genus in these failed implants, colonizing 31/33 (94%) of the fixtures. Proportions of Actinomyces growth of the total bacterial growth in the Actinomyces-positive fixtures varied from 0.01% up to 75%. A. odontolyticus was the most common Actinomyces finding, present in 26/31 (84%) Actinomyces-positive fixtures. Actinomyces naeslundii and A. viscosus were both detected in 10/31 (32%) and A. israelii in 7/31 (23%) fixtures. Other Actinomyces species, including A. georgiae, A. gerencseriae and A. graevenitzii, were detected less frequently. Our results suggest that Actinomyces species are frequent colonizers on failed implant surfaces, where A. odontolyticus was the far most prominent Actinomyces species.     

The occurrence of antagonistic actinomycetes in bulgarian soils and their antibiotic properties

Of 1448 actinomycete strains isolated from different types of soils 46% exhibited an antibiotic activity. Strains exhibiting a narrow antibiotic spectrum were more usual than those exhibiting a broad spectrum. An antifungal effect was the most common property. Strains exhibiting a considerable activity against pathogenic, phytopathogenic and dermatophytic microorganisms were found among isolated cultures. Fifty-three antagonistic actinomycetes were classified in 29 species.Actinomyces candidus, Actinomyces flaveolus, Actinomyces flavoviridis andActinomyces griseovariabilis were the most common. The antibiotic spectrum of individual strains belonging to the same species was qualitatively different in most cases.     

New producer of carminomycin, Actinomycer cremeospinus sp. nov.]

An actinomycete strain No. 85 was isolated from a soil sample on media with bleomycin. It was described as a representative of a new species. Actinomyces cremeospinus sp. nov. An antibiotic substance identical with carminomycin, an antitumor antibiotic was isolated from the culture fluid of the strain.     

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.     

Coaggregation properties of human oral Veillonella spp.: relationship to colonization site and oral ecology

The primary habitats of oral veillonellae are the tongue, dental plaque, and the buccal mucosa. Isolates were obtained from each habitat and tested for coaggregation with a battery of other oral bacterial strains. All 59 tongue isolates tested for coaggregation were Veillonella atypica or Veillonella dispar. All but one of them coaggregated with strains of Streptococcus salivarius, a predominant inhabitant of the tongue surface but not subgingival dental plaque. These tongue isolates were unable to coaggregate with most normal members of the subgingival flora such as Actinomyces viscosus, Actinomyces naeslundii, Actinomyces israelii, and Streptococcus sanguis. In contrast, 24 of 29 Veillonella isolates, of which 20 were Veillonella parvula from subgingival dental plaque samples, coaggregated strongly with the three species of Actinomyces, S. sanguis, and other bacteria usually present in subgingival plaque, but they did not coaggregate with S. salivarius. The majority of isolates from the buccal mucosa (42 of 55) has coaggregation properties like those from the tongue. These results indicate that the three human oral Veillonella species are distributed on oral surfaces that are also occupied by their coaggregation partners and thus provide strong evidence that coaggregation plays a critical role in the bacterial ecology of the oral cavity.     

Directed biosynthesis of proteolytic enzymes in Actinomyces thermovulgaris]

The biosynthesis of proteolytic enzymes in the thermophilic culture of Actinomyces thermovulgaris, strain T-54, was directed by changing the composition of the medium and the temperature of cultivation. A temperature of 40 degrees C is optimal for the growth and production of neutral and alkaline proteases. The maximum activity of acid proteases was found during the growth on a complex medium at 30 degrees C. An increase of temperature to 50 degrees C during the cultivation of the microorganism on a chemically defined medium resulted in its secondary growth and a sharp rise in the activity of alkaline and neutral proteases.     

Actinomyces--gathering evidence of human colonization and infection

The roles of the 'classical'Actinomyces spp. as colonizers of oral cavities of man and animals, in development of intra-oral infections and as agents of actinomycosis have been well documented. This mini-review focuses on perceptions of human colonization and infection that have emerged in the past decade, largely as a result of advances in classification, identification and direct detection from clinical material. Arguably, of the greatest importance is the recognition of actinomycosis as a major factor and indicator of poor prognosis in both infected osteoradionecrosis and bisphosphonate-associated osteonecrosis of the jaws. Among recently described species, Actinomyces graevenitzii has been isolated almost exclusively from oral and respiratory sites and may be a causative agent of actinomycosis. Conversely, several other Actinomyces spp. are isolated commonly from superficial soft tissue infections. Members of the genus Actinobaculum, which is closely related to Actinomyces, are strongly associated with urosepsis. Isolation and identification of Actinomyces and related genera by conventional methods remain difficult. Diagnosis is commonly belated and based solely upon histological findings. Development of direct detection methods may aid patient management and further elucidate clinical associations.     

Chemical and physical differentiation of superoxide dismutases in anaerobes.

Superoxide dismutase activity in crude or partially purified cell extracts from several species and strains of obligate anaerobe Bacteroides was inhibited instantaneously by NaN3 and was inactivated rapidly upon incubation with H2O2. The extent of NaN3 inhibition varied from 41 to 93%, and the half-life of the enzymatic activity in 5 mM H2O2 ranged from 1.2 to 6.1 min, depending upon the organism tests. When grown in a defined medium containing 59Fe, Bacteroides fragilis (VPI 2393) incorporated radiolabel into a 40,000-molecular-weight NaN3- and H2O2-sensitive superoxide dismutase but did not incorporate 54Mn into that protein under similar growth conditions. The anaerobe Actinomyces naeslundii (VPI 9985) incorporated 54Mn but not 59Fe into a NaN3-insensitive and H2O2-resistant superoxide dismutase. The apparent molecular weight of the superoxide dismutase from this and several other Actinomyces spp. was estimated to be 110,000 to 140,000. Comparison of these data with studies of homogeneous metallosuperoxide dismutases suggests that the Bacteroides spp. studied contain a ferrisuperoxide dismutase, whereas Actinomyces spp. contain a managanisuperoxide dismutase.     

Hepatic actinomycosis diagnosed by fine needle aspiration. A case report

A 43-year-old woman, a long-term intrauterine contraceptive device (IUD) wearer with a history of Actinomyces organisms seen in cervicovaginal smears, developed hepatic actinomycosis 13 months after removal of the IUD. The liver involvement was diagnosed by fine needle aspiration (FNA) cytology and the use of immunocytochemical techniques. Histopathologic examination of a right pelvic mass removed at surgical exploration revealed an Actinomyces tuboovarian abscess, the primary lesion in this case. The importance of cytologic detection of Actinomyces in cervicovaginal smears for the prevention of IUD-related pelvic inflammatory disease (PID) is discussed, as is the usefulness of FNA cytology in the diagnosis of systemic actinomycosis.     

SEROLOGICAL GROUPING OF ACTINOMYCES BY MEANS OF FLUORESCENT ANTIBODIES.

Slack, John M. (West Virginia University, Morgantown), Ann Winger, and Dane W. Moore, Jr. Serological grouping of actinomyces by means of fluorescent antibodies. J. Bacteriol. 82:54-65. 1961.-Serological groups A, B, C and D of actinomyces were established using fluorescent antibody techniques. One hundred and thirty-eight cultures were included in the study. Eighty-nine were classed in group A, 15 in B, 13 in C, and 21 in D.The isolates were from patients and animals with actinomycosis and from healthy human beings. There was no correlation between source of the isolate and serological group. Furthermore, no one species could be placed exclusively in one group although the majority of those designated as Actinomyces bovis were in group A.Seventeen anaerobic diphtheroids and seven Corynebacterium acnes isolates were placed in group A. One diphtheroid was in each of groups B and D. On this basis it is suggested that these organisms be included in the genus Actinomyces.Additional species of Corynebacterium as well as Lactobacillus Propionibacterium, Streptomyces, and Nocardia did not fluoresce with any of the group antisera.