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The authors have observed a case of Fusobacterium necrophorum associate with Actinomyces odontolyticus septicemia, which appears to be the first case reported. In a 19 year old man, 15 blood cultures allowed to isolate both germs. Clinical manifestations were: acute-like abdomen, encephalitis, myocarditis and pleural effusion. Treatment with amoxicillin and metronidazole was successful.
Five variants of Actinomyces lavendulae differing in the morphology of their colonies were found when natural variability of this organism was studied. A correlation was established between the colony morphology of the variants and their activity of cholesterol decomposition. The variants forming colonies of the basic and folded type had the highest activity. A variant with an elevated activity of cholesterol oxidase was selected. In order to maintain the high activity of the culture, it is necessary to examine its variability and to select variants corresponding to the basic type in their morphology.
When the levorin-producing organism Actinomyces levoris, strain 28 was cultivated on fermentation media under conditions of decreased oxidative-reduction values, a significant decrease in the processes of the culture multiplication and antibiotic production was observed. It was shown that the marked decrease in the catalase activity accompanied by a simultaneous increase in the dehydrogenase activity was one of the causes of the decrease in the processes of the culture multiplication and levorin synthesis. Addition of potassium chloride (0.2 per cent) stimulated the catalase activity and promoted the biomass increase and to some extent the antibiotic production.
The cytomorphology of an Actinomyces olivaceus culture was studied, in the course of its submerged cultivation in two media differing in phosphate content, in relation to lipid biosynthesis. The cells (including those grown under the conditions of phosphate deficiency in the medium) have well-developed membranous apparatus, particularly during the exponential growth phase and in the transition to the stationary phase whose time depends on the composition of the medium. No visible defects were found in the membranous apparatus of cells grown under the conditions of phosphate deficiency; the lipid component of these cells contained ornithinolipid instead of phosphatidyl ethanolamine. The fraction of ornithinolipid which had been found in this culture only under the conditions of phosphate deficiency was detected now in cells cultivated in a medium lacking CoCl2.6H2O but without phosphate deficiency during the stationary growth phase using the techniques of column and thin-layer chromatography. Nitrogen-containing polar lipids comprise cephalin (86.5%) and ornithinolipid (13.3%).
Submerged and aerial spores of Actinomyces chrysomallus, strain 2703, producing the antitumour antibiotic chrysomallin occupy, in their thermoresistance, an intermediate position between spores of other mesophilic cultures and endospores of some thermophilic actinomycetes. These spores were heated in water at 90 and 95 degrees C for 10 min. The fraction of highly thermoresistant spores constituted less than 0.001% of all the spores. It was found for the first time in the submerged culture. The structure of the submerged and aerial spores was studied by electron microscopy and was shown to be similar to that of the exotype spores. Heating at high temperatures of the spores often resulted in the strong variability of the culture and in the appearance of proactinomycete-like variants.
A 41-year-old man suffering from an actinomyces infection of the cornea of his right eye, was treated unsuccessfully with antibiotics especially intensive local and systematic therapy with penicillin, paracentesis of the anterior chamber with penicillin irrigation, and cautery of the corneal ulcer were fruitless. Finally, the corneal infection was cured by an urgent perforating keratoplasty.
The culture of Actinomyces griseus 15 was found to have a more complicated phage composition than it was supposed earlier. A new virulent mutant B has been isolated, which differs by its properties from the phage of Act. griseus 15, type I, isolated earlier. Phage lysates of the virulent mutants originating from different temperate phages of Act. griseus 15. Therefore, the culture of Act. griseus 15 is polylysogenic, defective lysogenic and contains at least three different phages.
Ultrastructural changes in the mycelium of Actinomyces (Streptomyces) chrysomallus 2703 producing the antibiotic chrysomallin in the process of submerged fermentation are described. When the antibiotic was produced at a high rate, most hyphae remained viable for a long period of time and had the ultrastructure typical of the young cells of actinomycetes. At the same time, a number of degenerative changes due to aging were observed; these resulted in autolysis. A decrease in the antibiotic titre was accompanied with intensive sporulation in a considerable number of the submerged hyphae. Structural changes in the sporeforming hyphae distinctly differed from those in the vegetative ones: the cell walls became thicker and numerous septa were formed. The exogenous formation of submerged spores in the culture under study has been studied in detail for the first time.
Actinomyces pyogenes was isolated from osteomyelitis lesions from the proximal tibia of mature tom turkeys. Gram-stained impression smears of the lesions resulted in bacteria that appeared as club-shaped, gram-positive pleomorphic rods. The bacteria grew better in a reduced-oxygen environment. The lesions were well demarcated and cavernous, ranging from purulent to caseous in consistency.
An orange antibiotically active substance isolated from the mycelium of a mutant strain of Actinomyces chrysomallus var. carotenoides was identified as a mixture of actinomycins according to its light absorption spectra, circular dichroism spectra, IR spectra and chromatographic comparison with the standard samples. A scheme for successive extraction of the biologically active substances from the mycelium resulting in isolation of a fraction enriched with antibiotic substances and a fraction enriched with pigments is presented. A method for separation and purification of 3 groups of biologically active substances from the mycelium enriched extract was developed.
Forty eight strains of Actinomyces lavendulae were studied. Morphological and physiological differences between the strains were found during growth on a liquid glucose-asparagine medium. In short-term experiments, the mycelium of 17 cultures of actinomycetes decomposed over 50% of cholesterol during two hours. The strains with a high activity of cholesterol decomposition (from 0.86 to 1.47-10(-2) conventional units of the specific activity) in short-term experiments were found: 556, 6959, 12348, 6960, 9840, and 10979. Introduction into the medium of such inductors as cholesterol, cortisone, cortisone acetate, and acetate of substance S had different effect on growth of the cells and their cholesterol decomposing ability.
Ultrastructural changes were found to occur in the mycelium of Actinomyces hygroscopicus, strain 33x, which produced an exocellular proteolytic enzyme during submerged fermentation, in both laboratory and semiindustrial conditions (in 100-1 fermenters). In the course of the enzyme accumulation, numerous vacuoles appeared in the hyphae, some hyphae became wider, and the cell walls were more loose. The greatest structural changes were found in the intracytoplasmic membrane systems. The ultrastructural changes of the mycelium are not presumably connected with the accumulation of the enzyme, but are the result of the differentiation of cellular structures during aging of the cells and their transition to the stage of autolysis.
The study of spontaneous variation of Act. werraensis not subjected to the treatment with mutagens and stabilizing selection revealed 6 variants within the homologous series of hereditary variation of apigmental actinomyces. The example of revealing the proactinomycete-like variants in Act. werraensis confirmed the prognosticating principle of the homologous series law in the hereditary variation of actinomycetes. Correlation between the cultural and morphological features of the spontaneous variants and the antibiotic-production level was shown. It was found that the variants of Act. werraensis had a high variation coefficient characteristic of the wild type actinomycetes. A possibility of increasing the biosynthetic activity of Act. werraensis by selection of spontaneous variants with artificial mutagenesis was shown.
GLC was used to study the composition of endocellular fatty acids of Actinomyces canosus 89 grown on a chemically defined medium and on a complex medium to which various components were added. Total lipids of the culture contain saturated and unsaturated fatty acids, from C13 to C18, with one or two double bonds. Addition of components to the medium stimulated the biosynthesis of myristic, stearic, oleic, and linoleic fatty acids. Changes in the composition of the growth medium modify the ratio between saturated and unsaturated fatty acids of total lipids, increasing the content of unsaturated fatty acids due to a higher rate of synthesis of linoleic and oleic fatty acids. An increase in the content of unsaturated fatty acids is a positive factor because these acids are involved in important physiological functions of both this organism and other living organisms.
A technique of "accelerated storage" was used to evaluate promptly the effectiveness of protective (suspension) media for lyophilization and further storage of spores of Actinomyces parvullus 99. The number of survived spores can be predicted using the Arrhenius diagram and the van't Hoff rule. Equine serum without a conserving agent was found to be the most effective protective medium for lyophilizing spores of Act. parvullus, as compared to such media as milk containing no fat or a mixture of 3 per cent solutions of gelatin and glucose.
Luminescence of Actinomyces enissus synthesizing heliomycin is caused by the action of UV; it is multicoloured, mosaic, and changes in the course of growth. Multicoloured luminescence is due to formation of substances with various colours of luminescence (antibiotics heliomycin and resistoflavin, coproporphyrins I and III, riboflavin, etc.); its mosaic character is caused by the presence in the population of variants with difference in the component composition of luminescent substances and the degree of differentiation of colonies.
Hydrolysis of olive oil by intact cells of Mycobacterium rubrum 403 and "acetone" preparations of Actinomyces streptomycini 116 was found to be inhibited by the following ions: Ca2+, Mg2+, Mn2+, Ba2+, Co2+, Cd2+, Cu2+, Zn2+, Fe2+, Fe3+, Ni2+. Olive oil is hydrolyzed by the growing culture of Act. streptomycini 116 only in the presence of bivalent metal ions. The biosynthesis of lipase by Mycobatcerium rubrum 403 and Act. streptomycini 116 is increased twofold by magnesium ions. The biosynthesis of lipase by Act. stroptomycini 116 is stimulated also by calcium ions.
The vegetative mycelium of a submerged culture of Actinomyces flavus 12 was studied by complex electron microscopy (negative and positive contrasting, cryofractography) in the course of biosynthesis of flavofungin. The antibiotic is accumulated first in the cytoplasm as singular small granules which later grow larger. Accumulation of flavofungin is accompanied with destruction of the cytoplasm, nucleoid and other structures. Secretion of the antibiotic is supposed to be accomplished according to holocrine type.