Streptomyces Parvulus
Mostrando 1-12 de 22 artigos, teses e dissertações.
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1. Produção e caracterização de protease fibrinolítica de Streptomyces parvulus DPUA 1573
RESUMO As proteases fibrinolíticas são capazes de degradar coágulos de fibrina formados dentro dos vasos sanguíneos, evitando a trombose intravascular. Em animais, a tromboflebite, que acomete frequentemente os equinos, ocasiona, em seus casos graves, a obstrução jugular e também um edema de laringe, derivando a obstrução das vias aéreas, o que pos
Arq. Bras. Med. Vet. Zootec.. Publicado em: 2017-02
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2. Atividade antimicrobiana de moléculas bioativas produzidas por Streptomyces parvulus DPUA 1573 frente a Staphylococcus spp. multirresistentes de mastite bubalina
Resumo: A mastite é uma inflamação na glândula mamária que pode acarretar perdas na produção e na qualidade do leite, gerando prejuízos econômicos para a pecuária leiteira. O tratamento é baseado na utilização de antibióticos, sendo, em muitos casos, ineficazes devido à resistência bacteriana já conhecida para esta doença. O objetivo deste
Pesq. Vet. Bras.. Publicado em: 2016-09
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3. Antimicrobial, Antioxidant and Cytotoxic Activity of MarineStreptomyces parvulus VITJS11 Crude Extract
The main aim of the study was to evaluate the bioactive properties of ethyl acetate crude extract of Streptomyces parvulus VITJS11 with a view to assess their therapeutic potential. The biological activity of ethyl acetate extract was tested against fungal and bacterial pathogens. The free radical scavenging potential of the crude extract was determined by D
Braz. arch. biol. technol.. Publicado em: 14/10/2014
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4. Production of polypeptide antibiotic from Streptomyces parvulus and its antibacterial activity
A highly potent secondary metabolite producing actinomycetes strain is isolated from marine soil sediments of Visakhapatnam sea coast, Bay of Bengal. Over all ten strains are isolated from the collected soil sediments. Among the ten actinomycetes strains the broad spectrum strain RSPSN2 was selected for molecular characterization, antibiotic production and i
Braz. J. Microbiol.. Publicado em: 08/04/2014
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5. Development of a bioprocess for the production of actinomycin-D
S. parvulus was selected from three species of Streptomyces that produce actinomycins, as it has the greatest antibiotic activity (152 mg/L) and produces only actinomycin-D. Aiming at improving the antibiotic production in shaken flasks, the substitution of glucose by fructose in concentrations of 20, 30 and 40 g/L was investigated. In all cases this replace
Brazilian Journal of Chemical Engineering. Publicado em: 2002-07
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6. A chemically defined medium for production of actinomycin D by Streptomyces parvulus
Um meio quimicamente definido composto de D (+) frutose, L (-) treonina, K2HPO4, MgSO4.7H2O, ZnSO4.7H2O, CaCl2.2H2O, FeSO4.7H2O e água deionizada, foi desenvolvido para maximizar a síntese de actinomicina D pelo Streptomyces parvulus DAUFPE 3124. O meio proposto resultou numa concentração antibiótica máxima de 133 mg/L enquanto que no meio inicial a pr
Brazilian Archives of Biology and Technology. Publicado em: 2001-09
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7. High-frequency fusion of Streptomyces parvulus or Streptomyces antibioticus protoplasts induced by polyethylene glycol.
Conditions were established for the regeneration of protoplasts of Streptomyces parvulus and Streptomyces antibioticus to the mycelial form. Regeneration was accomplished with a hypertonic medium that contained sucrose, CaCl2, MgCl2, and low levels of phosphate. High-frequency fusion of protoplasts derived from auxotrophic strains of S. parvulus or S. antibi
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8. Site-specific integration of the actinophage R4 genome into the chromosome of Streptomyces parvulus upon lysogenization.
The lysogenization of Streptomyces parvulus by actinophage R4 occurs by site-specific integration of the phage genome into the chromosome. The DNA fragments containing the attachment sites on the host chromosome, the phage genome, and the two junctions created by insertion of the phage genome were cloned and sequenced. The attachment sites were found to shar
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9. Development of a Chemically Defined Medium for the Synthesis of Actinomycin D by Streptomyces parvulus
A chemically defined medium, consisting of d-fructose, l-glutamic acid, l-histidine, K2HPO4, MgSO4·7H2O, ZnSO4·7H2O, CaCl2·2H2O, FeSO4·7H2O, CoCl2·6H2O, and deionized water, was developed for synthesis of high yields (500 to 600 μg/ml) of actinomycin D by Streptomyces parvulus. Under these nutritional conditions, growth and actinomycin formation did no
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10. Actinomycin Biosynthesis by Protoplasts Derived from Streptomyces parvulus
Conditions are described for the formation of protoplasts from Streptomyces parvulus that are able to synthesize actinomycin D de novo. Antibiotic synthesis by protoplasts, in contrast to that by mycelium, was sensitive to inhibition by actinomycin D and to a decrease in sucrose concentration. On the other hand, synthesis by mycelium was much more sensitive
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11. Metabolic regulation in Streptomyces parvulus during actinomycin D synthesis, studied with 13C- and 15N-labeled precursors by 13C and 15N nuclear magnetic resonance spectroscopy and by gas chromatography-mass spectrometry.
Recent studies have suggested that the onset of synthesis of actinomycin D in Streptomyces parvulus is due to a release from L-glutamate catabolic repression. In the present investigation we showed that S. parvulus has the capacity to maintain high levels of intracellular glutamate during the synthesis of actinomycin D. The results seem contradictory, since
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12. Protoplast fusion permits high-frequency transfer of a Streptomyces determinant which mediates actinomycin synthesis.
Prototrophic recombinants and heterocaryotic colonies developed at high frequency when protoplasts of nutritionally complementary actinomycin-producing and nonproducing strains of Streptomyces antibioticus were fused in the presence of polyethylene glycol and plated on minimal regeneration medium. Of the spores obtained from aerial hyphae of a single heteroc