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PubMedDate not supplied

[Calcium as a regulator of intracellular processes in actinomycetes: a review].

Data on the effects of calcium ions (Ca2+) on processes of morphological and physiological differentiation in cultures of actinomycetes have been reviewed, with emphasis on representatives of the genus Streptomyces. Evidence accumulated thus far, of the regulatory role of serine-threonine protein kinases in the differentiation and of the possible involvement of Ca2+-dependent protein kinases in secondary metabolism (including antibiotic biosynthesis) are analyzed. The possibility that regulatory elements of apoptosis (including Ca2+-dependent) function in actinomycetes is discussed. A hypothesis is advanced, according to which determinants of antibiotic resistance play a key role in the network of signal transduction systems of actinomycetes.

Actinobacteria↗
PubMedDate not supplied

Antifungal activity of some actinomycetes isolated from various habitats.

A total of 287 actinomycetes were isolated from 79 samples collected from five different habitats i.e., cultivated field soil (CFS), garden soil (GS), compost (CM), decaying organic matter (DOM) and stored agricultural products (SAP) of different localities of Sagar, Madhya Pradesh (23 degrees 50 degrees N latitude and 78 degrees 40 degrees E longitude). These were screened for antagonistic activity against Candida albicans, Aspergillus niger, Microsporum gypseun and Trichophyton sp. using 'Cross streak method'. Out of these, a total of 166 isolates were found antagonistic to Candida albicans, while 164, 134 and 132 actinomycetes showed antagonistic properties against A. niger, M. gypseum and Trichophyton sp., repectively. A total of 17 isolates showed very strong anticandidal activity causing total inhibition in the growth of C. albicans and hence, distribution of isolated test actinomycetes in different habitats and the cultural and antagonistic properties of selected 17 promising strains are reported here.

Actinobacteria↗
PubMed2005

[16S rDNA-RFLP analysis of actinomycetes associated with marine sponge Hymeniacidon perleve].

106 culturable symbiotic actinomycetes strains were isolated from intertidal marine sponge Hymeniacidon perleve collected from Chinese Yellow Sea. The 16S rDNA sequences of these strains were amplified and RFLP patterns were analyzed by digestion of 16S rDNA fragments with Hha I. 11 different patterns were identified, with confirmation by the RFLP analysis using Vector NTI simulation. Using Hha I RFLP patterns, the actinomycetes could be identified at the genus level. Phylogentic trees using 16S rDNA sequences were constructed. Majority of actinomycetes belonged to Streptomycetes (78). The other strains belonged to Nocardiopsis (18), Pseudonocardia (3), Nocardia (3), Micromonospora (2), Rhodococcus (1), Actinoalloteichus (1). Strain 177 is the candidate for new species of Actinalloteichus.

Actinobacteria↗
PubMed1991

[Development of integrative vectors for Actinomycetes--producers of antibiotics].

The integrative vectors pSU 475 and pSU 476 with variable numbers of copies per genome were developed for antibiotic producing actinomycetes. For this, the amplifying sequence AUD-Sr 1 of Streptomyces rimosus and the BamHIB fragment of the eSA 1 genetic element from Streptomyces antibioticus were used. The eSA 1 fragment was an element required for integration of a vector to the actinomycete chromosomes since it was homologous with the chromosomal DNAs of S. lividans, S. erythraeus and S. antibioticus. At the first stage the AUD-Sr 1 sequence within the actinomycete plastid pSU 23 was cloned by the vector pUC 19 to E coli. In that experiment the 12.4-kb plasmid pSU 449 was isolated. At the second stage the BamHIB-fragment of the eSA 1 element was incorporated into the resultant hybrid plasmid pSU 449. The 16.5-kb hybrid plasmids pSU 475 and pSU 476 were isolated. In these plasmids the BamHIB fragment of eSA 1 was present in two orientations. The developed vectors were useful in cloning DNA to S. lividans and S. erythraeus.

Anti-Bacterial Agents↗
PubMedDate not supplied

[Formation of dextranases by mycelial fungi and actinomycetes].

The dextranase activity of cultures of mycelial fungi of different genera and actinomycetes from the Chromogenes species of the Actinomyces genus was studied. About one third of the mycelial fungi and 8% of actinomycetes showed dextranase activity. The resulting extracellular dextranases demonstrated on endotypic pattern of action on the substrate. Actinomycete dextranases were several times more active than fungal dextranases and exhibited a significant activity in the neutral and weakly alkaline medium. Highly productive strains that are promising as dextranase producers were isolated.

Actinomyces↗
PubMedDate not supplied

The prevalence of actinomycetes-like organisms found in cervicovaginal smears of 300 IUD wearers.

The association of Actinomyces with IUD wearers has been widely documented and the possibility of the recognition of actinomycetes-like organisms in routine Papanicolaou-stained cervicovaginal smears has been reported. We conducted a retrospective study of IUD wearers to determine the prevalence and significance of actinomycetes-like organisms found in such smears. Three hundred smears from current IUD wearers were rescreened for actinomycetes-like organisms. Of this group, 200 patients were from a public health family planning clinic, and 100 were private patients. The incidence for the public health group was 25.5% and for the private patient group, 8%. A case history of actinomycosis is included. Findings such as other infectious agents, abnormal cytology and symptoms are also discussed. Although the presence of Actinomyces probably represents an opportunistic infection, the threat of pelvic actinomycosis with serious complications poses a management problem to the clinician when Actinomyces is reported in a routine Papanicolaou smear. Our findings lead us to question the practicality of the earlier recommendations of IUD removal and antibiotic therapy.

Actinomyces↗
PubMed1988

[Bacteriolytic enzymes produced by actinomycetes. I. The physicochemical properties of the enzymes and the spectrum of their lytic action].

This review is devoted to the bacteriolytic enzymes produced by many actinomycetes, mainly by Streptomyces genus. The bacteriolytic enzymes hydrolyse the specific bonds in bacterial peptidoglycans and cause the solubilization of the cellular walls and the disintegration of the bacterial cells. Many of the enzymes are purified to the electrophoretic homogeneity. The actinomycetes form the endo-N-acetylmuramidases more often, then the endopeptidases follow according to the frequency of occurrence, while the amidases and endo-N-acetylglucosaminidases are met rather seldom among the streptomycete-producers. The known amidases and exo-enzymes which are also produced by some species of actinomycetes are not related to the lytic enzymes proper. Almost all known endopeptidases from streptomyces hydrolyse the bridge peptide bonds in which the carboxyl group of terminal D-alanyl of peptide chain is involved. The bacteriolytic spectra of the different muramidases differ from each other and essentially differ from the spectrum of the egg-white lysozyme. Some endomuramidases from streptomyces are able to hydrolyse streptococci and some other important from the practical point of view microorganisms resistant to the action of lysozyme.

Actinomycetales↗
PubMed1987

Kitasatosporia setae, an interesting actinomycete strain isolated from Spitsbergen soil.

The phenotypic and genotypic properties as well as cell chemistry of an interesting actinomycete, which converted certain azacarbazoles into highly cytotoxic derivatives, were established. The strain was also compared with two similar Japanese actinomycetes of Kitasatosporia gen. nov. A great resemblance between the strains was observed. Apart from similar phenotypic properties they were characterized by contents of both L- and meso-DAP, glycine and galactose as the main cell wall components. They proved to have the same phospholipid, glycolipid and fatty acid patterns. The guanine-plus-cytosine contents of the deoxyribonucleic acids of the strains averaged 72.5 and there was a high degree of homology between the DNAs of the strains (approximately 80%). These data provide evidence that the Spitsbergen isolate and the Japanese actinomycetes belong to one genomic species.

Actinomycetales↗
PubMed1986

[Role of levorin and lytic enzymes in the interrelations of yeasts and actinomycete in a mixed culture].

Interrelation of yeasts and the actinomycete producing levorin, Streptomyces levoris in mixed cultures was studied. It was found that death of the accompanying microorganisms during fermentation with the two cultures was mainly due to the effect of the actinomycete lytic enzymes. The level of the enzymatic lysis depended on the genus and species characteristics of the organisms used in mixed cultures. By the end of the fermentation process the culture fluid contained no organisms with respect to which the lysoenzymes of S. levoris were highly active. In this case mixed cultivation of the actinomycete and yeasts resulted in increasing antibiotic synthesis by 45-48 per cent as compared to the control. The yeasts hydrolyzed by the S. levoris yeastlytic enzymes with difficulty or slightly remained viable up to the end of mixed cultivation and lowered the level of the antibiotic activity.

Antifungal Agents↗
PubMed1978

[Lysis of the cellular walls of Streptococcus group A by enzymes produced by actinomycetes].

More than 80 cultures of actinomycetes belonging to different taxanomic groups were studied with a purpose of screening actinomycetes actively producing enzymes lyzing the cell walls of group A streptococci. 31 strains of the actinomycetes producing enzymes which lyzed the cell walls by 20-50 and 60-80 per cent within 1 and 4 hours respectively were selected. The proteolytic activity of the enzymes produced by these strains was also studied. It was shown that 4 cultures, i.e. Actinomyces albus, strains 6 and 9, Actinomyces levoris, strain 29 and Actinomyces gibsonii, strain 42 were of interest as organisms producing enzymes which lyzed the streptococcal cell wall without impairing its antigenic components.

Actinomycetales↗
PubMed1985

[Experience with long-term preservation of international-standard cultures of Actinomycetes].

The results of the study on long-term maintenance (1-12 years) of 453 reference cultures of actinomycetes are presented. The cultures were maintained with the following methods: lyophilization, soil cultures and periodical passages on agarized nutrient media. Lyophilization was most efficient for storage of the majority of the cultures: 346 strains (77.4 per cent) preserved high viability over the observation period of 11-12 years. Lyophilization appeared less favourable for the cultures with low sporulation. The efficacy of the method of soil cultures on long-term storage of the whorl actinomycetes was low: 88 per cent of Streptoverticillium lost their viability within 1-2 years. However, this method was valuable for stabilization of the taxonomic features of streptomycetes. The maintenance of the actinomycetes by regular passages on agarized media every 6 months resulted in the changing of the cultural and morphological features in a number of the strains.

Actinomycetales↗
PubMed1982

[Distribution of actinomycetes of the genus Actinomadura in the light chestnut soils of Volgograd Province and their antagonistic properties].

Prevalence of the actinomycetes of the Actinomadura genus in the virgin and cultivated light chestnut soils of the Volgograd Region was studied. It was shown that Actinomadura were one of the constituents of the actinomycetous flora of these soils. No significant changes in the number of the Actinomadura and the total number of the actinomycetes were observed in the cultivated and virgin soils. The cultures of Actinomadura isolated from the virgin and cultivated soils belonged to 17 and 18 known species, respectively. Some ecological indices were determined for estimation of the similarities and differences in the species structure of Actinomadura in the virgin and cultivated soils. It was shown that cultivation of the soils increased the species variety, equalization and general variety of Actinomadura. In the process of the species identification of Actinomadura the chemical nature of the pigments of the substrate mycelium of the same group of the isolates and the type culture of A. salmonea ATCC 33580 was studied. The pigment responsible for the colour of the substrate mycelium of A. salmonea belonged to the maduromycin group. The antagonistic properties of the Actinomadura isolated from the soils were studied. The isolates had a moderate antagonistic activity mainly against grampositive organisms.

Actinomycetales↗
PubMedDate not supplied

[Use of molybdenum media with glycerin and admixtures of unassimilated polyols for differentiating actinomycetes].

Actinomycetes were cultivated in a medium containing from 0.15 to 0.2% of ammonium molybdate, glycerol and from 0.25 to 1% of polyol which was not assimilated by the cultures and inhibited the production of molybdenum blue in many actinomycetes. The cultures differed in their susceptibility to the inhibition by various polyols. There were not two polyols that would produce an identical effect on all of the cultures. Correlations were established in the action of polyols. The differences in the formation of molybdenum blue can be used for the differentiation and identification of actinomycetes to subdivide them into groups according to their sensitivity to inositol, mannitol, D-arabitol, xylitol, sorbitol, L-arabitol and dulcitol and according to their resistance to dulcitol (minimal, average and maximal resistance). The paper presents schemes for subdividing groups into subgroups and for establishing the properties.

Actinomycetales↗
PubMedDate not supplied

[Systematic position of an autotrophic actinomycete isolated from a floodplain marsh near Moscow].

A hydrogen-oxidizing actinomycete (Z-1046) was isolated from a flood-plain marsh in the Moscow Region. Its taxonomy was compared with that of similar cultures belonging to international special standards of actinomycetes (ISP). The strain Z-1046 was found to be identical with Streptomyces autotrophicus ISP-5011 (RIA-1008, ATCC-19727, CBS-466.68, IFO-12743). It has been also shown that the generic identification of the standard culture ISP-5011 is erroneous: as Hirsch (1960) holds, the culture belongs to the genus of Nocardia (Proactinomyces). Thus, the culture Streptomyces (Actinomyces) autotrophicus ISP-5011 must be eliminated from the international special standards of the genera Streptomyces and Streptoverticillium. The autotrophous actinomycete that we have isolated is classed as Proactinomyces autotrophicus comb. nov. (=Streptomyces autotrophicus Takamiya et Tubaki, 1956, ISP-5011, RIA-1008, ATCC-19727, CBS-466.68, IFO-12743, =Nocardia autotrophica, Hirsch, 1960).

Actinomycetales↗
PubMed1982

[Multiple antibiotic resistance of actinomycetes from the nodules and rhizosphere of the alder].

A total of 10 actinomycetous strains isolated from the root nitrogen-fixing tubercles and rhizosphere of alder were studied with respect to their sensitivity to 17 widely used antibiotics. By their cultural and morphological properties the isolates belonged to 3 groups. The strains were characterized by multiple resistance to the antibiotics. They were resistant to nalidixic acid, clindamycin and lincomycin and sensitive to novobiocin and vancomycin. Their behaviour with respect to the other antibiotics was diverse. The resistance spectra were specific of the strains belonging to groups I and II. The strains of group III were more heterogeneous by the character of their antibiotic sensitivity. The results of the study may be used for development of selective conditions for isolation of unusual actinomycetes from the alder tubercles and rhizosphere. The data on the diverse effect of some antibiotics on the growth and development of aerial mycelium of the strains belonging to group III may be used in the studies on cell differentiation of actinomycetes.

Actinomycetales↗
PubMedDate not supplied

[Date palm and fusariosis. VIII.--Parasitism of "Fusarium oxysporum" f. sp. "albedinis" by an actinomycete (author's transl)].

Fortuitous growth of an actinomycete on Fusarium oxysporum f. sp. albedinis culture has shown a host-parasite process. As a response to the actinomycete, the fungus produces thallospores with various forms which can germinate faster than the non-parasited F. o. albedinis microconidies. However, the strains obtained from thallospores showed as sensible as the mother strain towards actinomycete action.

Actinomycetales↗
PubMed1980

Response of developing branched bacteria to adverse environments. II. Micromorphological effects of lysozyme on some aerobic actinomycetes.

An early symptom of lysozyme treatment of developing actinomycete microcolonies is hyphal tip swelling, illustrating the plasticity of this region in relation to filament extension. The reaction is not limited to true mycelia of Streptomyces, Streptoverticillium and Rhodococcus but is also characteristic of unbranched filaments of actinomycetes exposed during their elongation stage. On the other hand rods whose extension has ceased and which are undergoing fragmentation do not show any localized weakness but a generalized lysis. Results are discussed with reference to polarity of growth in actinomycetes.

Actinomycetales↗
PubMed1995

[The influence of diesel fuel oil on the number of bacteria, fungi, actinomycetes and soil microbial biomass].

In laboratory conditions the influence of Diesel fuel oil on the total number bacteria, fungi, actinomycetes and content of microbial biomass in soil was studied. The fuel oil was applied at dosage of 1, 2 and 5 g/100 g of soil. Samples of soil were analysed 1, 7, 14, 21 and 150 days after oil applied. Microbiological analyses involved determinations of the total number of bacteria and actinomycetes (on Bunta-Roviry medium) and fungi (on Martin's agar) by the plate method. The content of microbial biomass in soil was determined using the physiological method of Anderson and Domsch. Diesel fuel oil application caused the changes of total number of investigated groups of soil microorganisms. These results were confirmed by the investigated groups of soil microorganisms. These results were confirmed by the investigation on microbial biomass in soil. In the most of cases the fuel oil was the most stimulated for the number of bacteria and the most inhibited for actinomycetes in comparison with soil without oil (control). From soil with Diesel fuel oil addition Pseudomonas, Arhtrobacter, Bacillus and Penicillium, Aspergillus, Fusarium, Trichoderma strains were isolated. The possibility of the fuel oil as source of carbon utilization by these strains will be investigate.

Actinomycetales↗