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We describe two immunosuppressed female patients with fever and Actinomyces odontolyticus bacteremia, a combination documented once previously in an immunocompetent male patient. The patients were treated with doxycycline and clindamycin; these drugs, with beta-lactams, are effective treatment for A. odontolyticus infections.
A five-month-old, male Brazilian fila presented with a three-day history of a focal swelling in the left superior palpebra and a focal, subcutaneous swelling over the dorsal cervical region. Both lesions initially responded to warm compresses and a two-week course of oral amoxicillin-clavulanic acid therapy. The eyelid swelling recurred after discontinuation of the oral antibiotic therapy. The lesion was progressive and was refractory to trimethoprim-sulfadiazine therapy. Culture and sensitivity performed from a surgical biopsy sample of the eyelid mass identified Actinomyces viscosus and other bacterial genera. A combination of surgical debulkment, Penrose drain placement, and a one-month course of oral oxacillin therapy has resulted in clinical regression of the lesion at a six-month postoperative evaluation.
Pulmonary actinomycosis is an uncommon infection whose diagnosis is often delayed as clinically the disease may mimic tuberculosis or cancer. It is rare in children. We present the first report from Australasia of a case of Actinomyces meyeri pneumonitis in a 13-year-old boy.
Cetoniacytone A (1) and some related minor components (2, 6, 7) were produced by Actinomyces sp. (strain Lu 9419), which was isolated from the intestines of a rose chafer (Cetonia aureata). The structures of the novel metabolites were established by detailed spectroscopic analysis. The absolute configuration of 1 was determined by X-ray analysis and derivatisation with chiral acids. 1 exhibits a significant cytotoxicity against selected tumor cell lines. The biosynthesis of 1 was studied by feeding 13C labelled precursors. The results suggest that the characteristic p-C7N skeleton of the aminocarba sugar is formed via the pentose phosphate pathway by cyclisation of a heptulose phosphate intermediate.
Intracellular growth of a thermoinduced prophage was caused by the action of elevated temperature on the lysogenic culture of Actinomyces lividans 66 (phiC31 ct22). The growth took place in the nucleoid where loose, oval or round, particles consisting of twisted NA threads were formed. Later, electron-dense phage heads, covered with a sheath, appeared, and still later--phage tails. Thermoinduction was terminated by lysis of the mycelium of the actinomycete when mature particles of the actinophage were liberated into a surrounding medium.
Protoplasts of Actinomyces hygroscopicus were obtained in a hypertonic medium containing 10.3% sucrose. Lysozyme was employed as a lysing agent at a concentration of 1 mg/ml. The cells were subjected to lysis during 3-4 hours at 37 degree C, the concentration of biomass being 0.05 g of dry mycelium per 1 ml of hypertonic solution. Production of protoplasts was controlled by phase-contrast microscopy; the amount of the protoplast was determined by optical density at lambda=530 nm. The highest amount of the protoplasts was obtained during growth of the culture on a medium containing 0.5% glycine. The membrane fraction was isolated after lysis of the protoplasts in a hypotonic medium, treatment with DNase and RNase, and centrifugation at 22,000 g in the cold. Production of the membranes was controlled by electron microscopy. The yield of the membranes was 17-19% of the dry mycelium weight. They contained about 35% of lipids, 50% of protein, and 5% of RNA.
The antibiotic activity and fractional composition of the supernatant of the homogenate of Actinomyces streptomycini B-6 spores were investigated. The homogenate supernatant was of yellow colour and showed antibiotic activity when used as the test-organism of the culture St. aureus 209. The antibiotic activity was associated not with the homogenate pigment but with the colourless substance referring to streptomycins which was contained in spores.
The structure and function of the mycelium were studied with active and inactive variants of Actinomyces parvillus producing actinomycin D. Changes in the morphology were found in the hyphae of the active variant during its growth and production of the antibiotic: the cell wall became first thicker in the course of growth and then thinner with aging; the ribosomes aggregated prior to intensive synthesis of actinomycin but disintegrated later into fine-granular regions; electron-trasnparent bodies of irregular shape appeared in the cytoplasm, and their content was liberated into the medium upon lysis of the cytoplasmic membrane and cell wall. These changes were not detected in the mycelium of the inactive variant. The disintegrated mycelium of the active variant was studied by differential ultracentrifugation, and the electron-transparent bodies in the cells were presumed to be of the antibiotic nature. A capsule is formed around the hyphae at the beginning of the antibiotic synthesis, and thickens in the course of growth. Intrahyphal hyphae are very often encountered in the culture. Possible mechanisms protecting cells in unfavourable conditions are discussed.
Properties of a dark-brown pigment complex isolated from the spores, mycelium and cultural broth of Actinomyces umbriferus by a conventional technique were compared. The complex consists of three fractions: one is a true melanin while two other fractions differ by several characteristics from melanins and from each other. The fraction which is most similar to melanin prevails in the spores, is contained, in a relatively small amount, in the mycelium, and is absent from the cultural broth. Melanin isolated from the spores has a low relative content of carbon and nitrogen and a higher ash content as compared to melanin isolated from the vegetative mycelium. The pigment complex of the spores is characterized also by differences in properties of the first isolated fraction. The pigment complex from the cultural broth differs from the complex of the mycelium and spores by properties of the studied fractions.
We report a case of endocarditis caused by Actinomyces viscosus in a previously healthy young adult with no known identifiable portal of entry. Infective endocarditis caused by A viscosus is uncommon; two cases of endocarditis caused by this species have been previously reported. Primary actinomycotic endocarditis has been previously reviewed in 1993; we provide a review of additional cases since that report. In comparing our case with the other reported cases, we found that actinomycotic endocarditis (1) occurs in a wide spectrum of age, (2) affects primarily males, (3) has a high propensity for systemic embolization, and (4) has involved only native heart valves. The disease is manifested by the typical signs and symptoms of infective endocarditis and is curable with long-term penicillin therapy. The use of echocardiography in the diagnosis of endocarditis, techniques for improving the microbiologic diagnosis of endocarditis, and current indications for surgical intervention are discussed.
Some characteristics of UV-induced luminescence were studied with Actinomyces olivocinereus producing the antibiotic heliomycin. The luminescence of the growth medium was found to be caused not by heliomycin, but by some other factors. The luminescence of heliomycin in the colonies was quenched as a result of its screening with melanin pigments located in a layer between the aerial and substrate mycelium.
The persistence of anaerobic bacteria in the root canal system often leads to treatment failure. One possible reason for this may be the retention of micro-organisms in the dentinal tubules of root canal walls. This study was performed to compare the effectiveness of two root canal medicaments and a chlorhexidine solution in disinfecting Actinomyces israelii-infected root canal walls and dentinal tubules in vitro. Dentinal tubules of root canal walls of human teeth were experimentally infected with A. israelii. The root canals were exposed to either iodine potassium iodide, calcium hydroxide or 2% chlorhexidine for periods of 3, 7 and 60 days. At the end of the medication periods samples were removed at different depths and tested for A. israelii viability. Chlorhexidine was the only disinfectant that was able to eliminate A. israelii from all the samples after 3, 7 as well as 60 days while 25% of the specimens treated with iodine potassium iodide and 50% of the specimens treated with calcium hydroxide still had viable A. israelii after treatment. It is clear from this study that 2% chlorhexidine is superior to iodine potassium iodide and calcium hydroxide in its ability to remove A. israelii from infected dentinal tubules. However, in vivo trials need to be undertaken before its clinical use can be recommended.
The amino acid composition of the protease (TI-Ajl) inhibitor from Actinomyces janthinus 118 has been determined. It was shown that the TI-Ajl, S-SI and plasminostreptin inhibitors of trypsin and subtilisin have a number of common features: number of double bonds, tryptophane and tyrosine residues, prevalence of the acidic amino acids over the basic ones, ets. The effect of chemical modification of amino groups, arginine, tyrosine and methionine residues on the inhibitory activity of TI-Ajl was studied. The data obtained are indicative of the presence of two active centers of the inhibitor. The antitrypsin center contains a lysine residue.
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.
Variation of Actinomyces chromogenes var. trienicus 141-18 MSU, an organism producing trienin was studied under laboratory conditions. Nine stable spontaneous variants were isolated from the population of the initial culture when grown on Gause medium No. 1. The variants varied in differentiation and biosynthetic capacity, including such characteristics as size and form of the colonies, ability for formation of the aerial mycelium and its colour, capacity for sporulation, form of the spore chains and antibiotic production property. In the secondary structures the spores formed only in 6 variants out of 9 isolates. The spore form and spore membrane surface were close in all sporogenic variants, while there were significant differences in the structure of the sporophores. The variants forming the aerial mycelium of the same colour as that of the initial culture did not differ from it also by the nature of the spore chains (spirals with 3--8 turns). The variants with lighter aerial mycelium than that of the initial population formed straight sporophores or spirals with a small number of the turns (1--3). The comparative study of the antimicrobial spectrum of the variants and the component composition of the synthesized antibiotic complex showed that the asporogenic variants and dwarf variant signifcantly differed with respect to their phenotypes from the other cultures and had no antagonistic action. One of the assporogenic variants had only insignificant activity. All the spore forming variants did not differ from the initial culture in the complex of the antibiotics synthesized.
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.
A fibrinolytic enzyme was isolated from the cultural broth of Actinomyces thermovulgaris T-54 by precipitation with ammonium sulphate to 0.8 saturation and chromatography on GE-cellulose and CM-cellulose. The enzyme is homogeneous as was confirmed by disk electrophoresis in polyacrylamide gel. Some properties of the enzyme were studied. A modification of the method is suggested to assay the fibrinolytic activity.
An isolate of marine actinomyces MB-97 identified as Streptomyces microflavus could successfully colonize in the rhizoshpere of soybean, and inhibit Penicillium purpurogenum, a soybean deleterious rhizospheric microorganisms. After applied MB-97, the ratio of bacteria/fungi in the rhizosphere of soybean was increased, and the soil became to be "Bacterial type" from "Fungal type". The populations of P. purpurogenum were apparently suppressed about 80%, and the harm of toxins in soil was weak. The soybean root rot caused by soilborne fungi such as Fusarium was decreased 50%, and MB-97 could stimulate the growth of soybean seedlings. In field study, the mean yield of soybean raised by 15.2%, implying that Streptomyces microflavus was an effective plant growth-promoting rhizobacteria on soybean.