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At least 19 recordsLinked to original sources
PubMed1979

Production of beta-lactamase by non-streptomyces Actinomycetales.

Supernatants and whole cells from fermentation broths of Micromonospora, Nocardia, Oerskovia, and other genera of the Actinomycetales were examined for the presence of beta-lactamase activity by using the chromogenic cephalosporin 87/312. Nearly 60% of the 250 isolates examined produced detectable levels of beta-lactamase. All enzyme preparations were active over a range of pH values from 6.5 to 8.2, with maximum activity occurring between 7.0 and 7.8. The preparations varied in their stability at 60 degrees C. An examination of selected enzyme preparations revealed a similarity between substrate specificities of the non-Streptomyces Actinomycetales and gram-negative-bacterial beta-lactamases.

Actinomycetales↗
PubMed1975

Immunophyletic relationships between actinomycetales and eubacteriales determined by examinations of their cytoplasmic antigens.

Cytoplasms obtained from a total of 205 different strains of Actinomycetales, Eubacteriales, Lower Fungi, and Protozoa were examined against selected anti-cytoplasm antisera using the immunodiffusion and counterimmunoelectrophoresis procedures. Immunological relationships between the different genera have been revealed and, in respect to Eubacteriales, the possible immunophyletic determinants have been discerned. Cytoplasms of Enterobacter, Clostridium, Staphylococcus, and Diplococcus were found to retain the significant linkage determinants between large groups of Eubacteriales and Actinomycetales. Evolutionary implications of the findings are discussed.

Actinomycetales↗
PubMedDate not supplied

[Comparative characteristics of the ability to coagulate milk in different representatives of the order Actinomycetales].

The ability to clot milk was studied among 482 cultures of Actinomycetales. The highest activity was manifested by thermophilic actinomycetes, the next come globisporous, white, and gray groups of the genus Actinomyces. Cultures belonging to the genera Mycobacterium and Mycococcus did not clot milk. The ability to clot milk can be used as an additional taxonomic index while studying ray fungi.

Actinomyces↗
PubMed1979

[Actinomycetales in cutaneous pathology].

After discussing the classification of the Actinomycetales, the authors give a detailed description of the epidemiology and particularly of the clinical features of cutaneous diseases induced by genera such as Actinomyces, Norcardia and Streptomyces. Histopathological and immunological studies, together with laboratory and differential diagnostics, are also examined. In the last section, present therapeutic treatments are briefly outlined.

Actinomyces↗
PubMed1979

Studies on Actinomycetales producing antibiotics only on agar culture. I. Screening, taxonomy and morphology-productivity relationship of Streptomyces halstedii, strain SF-1993.

Soil Actinomycetales that produce antibiotics during growth on agar but not in submerged culture were searched for and about 25 strains were obtained. One of these, Streptomyces halstedii, strain SF-1993, which produces an antibiotic designated SF-1993 was studied taxonomically and morphologically. The antibiotic-productivity of strain SF-1993 was correlated with mycelial morphology. The vegetative mycelium was filamentous in antibiotic-producing agar cultures, but fragmented in non-producing submerged cultures. By maintaining submerged cells filamentous, production of antibiotic in the submerged fermentations was accomplished. Filamentation was maintained by the use of diluted media or non-fragmented mutant substrains.

Agar↗
PubMed1979

Glaucescin, a bacteriocin-like substance from Streptomyces glaucescens.

Streptomyces glaucescens ETH 22794 produced a variety of antibiotic substances. Besides low molecular weight antibiotics like hydroxystreptomycin and the tetracenomycins, this strain excreted glaucescin, a high molecular weight product with bacteriocin-like properties. In plate tests the antagonism of glaucescin against Streptomyces canadiensis was masked by the large inhibition zone caused by the tetracenomycins. Glaucescin activity was revealed when a tetracenomycin-resistant mutant of S. canadiensis NRRL 3155 was used as an indicator. Glaucesin was produced on complex and minimal solid and liquid media. It was not inducible by mitomycin C. The killing activity of glaucescin was thermolabile and resistant to DNAase, RNAase, various proteinases, and lipase. Its apparent molecular weight was estimated as 196000 by gel filtration and glycerol gradient centrifugation. Glaucescin preferentially killed outgrowing spores of S. canadiensis. Resting spores and mycelium were considerably less sensitive to the inhibitor, and adsorption of glaucescin by S. canadiensis paralleled sensitivity. The activity spectrum of the bacteriocin was restricted to spore-forming Actinomycetales. Non spore-forming nocardiae and a variety of Gram-positive and Gram-negative bacteria were resistant to glaucescin.

Actinomycetales↗
PubMed1979

Demonstration of tuberculostearic acid in sputum from patients with pulmonary tuberculosis by selected ion monitoring.

Selected ion monitoring was used to detect tuberculostearic acid (10-methyloctadecanoic acid) in sputum from patients with pulmonary tuberculosis. The specimens were autoclaved, lyophilized, extracted, and methanolysed before being subjected to thin-layer chromatography and injected into the gas chromatograph/mass spectrometer. Tuberculostearic acid could be detected in five of six tuberculous sputum specimens containing acid-fast rods detectable by light microscopy of Ziehl-Neelsen stained smears. After the sputum specimens had been cultured for five days on Löwenstein-Jensen medium, when still no colonies could be observed visually, the presence of tuberculostearic acid was demonstrated in all six cases of tuberculosis. In corresponding analyses of sputum from eight patients with non-tuberculous pneumonia, tuberculostearic acid was not found. This fatty acid, the presence of which was also demonstrated in cultures of various mycobacterial and nocardial species, is characteristic of organisms of the order Actinomycetales. The demonstration of tuberculostearic acid in sputum specimens may constitute a rapid and sensitive way of diagnosing pulmonary tuberculosis.

Chromatography, Gas↗
PubMed1976

[Pulmonary reactions to non-infective antigenic contaminants].

There are different categories of non-infectious antigenic contaminants capable of provoking pulmonary reactions: thermophilic actinomycetales, fungi, vegetable particles, protein antigens, arthropods, drugs; their identification is based on their isolation, culture, and the study of their biochemical composition. The pulmonary reactions depend on the size and number of antigenic particles inhaled and by the underlying background. The immunological mechanisms brought into play a complex Arthus's phenomenon: in addition to the IgGs, the IgEs and the different factors of complement intervene; the recent acquisitions of immunomorphology enable better comprehension of the histogenesis of the pulmonary granuloma. The diagnosis of extrinsic allergic alveolitis is founded on well defined criteria of clinical, radiological, respiratory functional, immunological and histophthological order. These conditions are met with in agricultural, industrial and urban environments or are related to iatrogenic diseases. Many problems still remain obscure with regards to the pathogenesis and integration within the framework of immunological pneumonia of various conditions, and especially certain sarcoidosis.

Antibodies↗
PubMed1979

Bacterionema matruchotii ocular infections.

One case of endophthalmitis and two cases of corneal ulceration, each occurring in a structurally altered eye, were associated with Bacterionema matruchotii, a gram-positive filamentous bacillus.

Actinomycetales↗
PubMed1977

Modified techniques for the isolation of Dermatophilus spp. from infected material.

Two improved techniques are described for the isolation of Dermatophilus spp. The first is suitable for samples of scab from lesions of the disease in animals, except for sheep affected with lumpy wool. The second is for the isolation of the organism from samples of lumpy wool in sheep. Both techniques are simple, rapid and reliable and are based on releasing the organism by pulverizing the scab and then by suppressing contaminants by including polymixin B sulphate in the medium. Excellent results are obtained with or without pre-incubation exposure to CO2.

Actinomycetales↗
PubMed1979

Humoral and cell-mediated immune response to crude antigens of Dermatophilus congolensis during experimental infection of rabbits.

Rabbits were infected with Dermatophilus congolensis and tested for humoral immune response by indirect haemagglutination and for cell-mediated immune response to crude antigens of D. congolensis. Lymphocyte transformation and macrophage migration inhibition assays were used as in vitro correlates of cell-mediated immune response while cutaneous delayed hypersensitivity was used in vivo. Endo-antigen and whole cell antigen were found to significantly induce cell-mediated immune response. In contrast, humoral responses were found to be more significantly induced by exo-antigen. A biphasic immune response was revealed by the lymphocyte transformation test.

Actinomycetales↗