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1.
Biochim Biophys Acta ; 1074(2): 237-42, 1991 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-1648397

RESUMEN

The cell wall of Streptomyces rutgersensis var. castelarense contains structurally different chains of 1,3-type glycerol teichoic acid. Part of the molecules consisting of 20-25 monomers, carry on every third glycerol phosphate unit (at C-2) alpha-glucosamine residues, only half of which are N-acetylated. There are chains with O-lysine groups, and free nonsubstituted ones. The chain structure has been ascertained by chemical analysis and 13C- and 1H-NMR spectroscopy.


Asunto(s)
Pared Celular/química , Lipopolisacáridos/aislamiento & purificación , Streptomyces/análisis , Ácidos Teicoicos/aislamiento & purificación , Secuencia de Carbohidratos , Glicósidos/aislamiento & purificación , Hidrólisis , Lipopolisacáridos/química , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Monoéster Fosfórico Hidrolasas , Polímeros/aislamiento & purificación , Ácidos Teicoicos/química
2.
J Chromatogr ; 547(1-2): 411-8, 1991 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-1894724

RESUMEN

Thin-layer chromatography coupled with flame ionization detection was used to develop a method to separate and to determine simultaneously three polyether carboxylic ionophore antibiotics (abierixin, nigericin and grisorixin) produced by Streptomyces hygroscopicus NRRL B 1865. Various proportions of chloroform, methanol and formic acid (or acetic acid as a substitute for formic acid) were used in the developing solvent to determine changes in RF values of the antibiotics and to allow conditions for maximum resolution to be obtained. Development on Chromarods SII with chloroform-methanol-formic acid (97:4:0.6, v/v/v) gave satisfactory and reliable separations of the three polyether antibiotics. Under these conditions, the internal standard methyl desoxycholate was found to be suitable for their simultaneous determination in the lipid extracts of Streptomyces hygroscopicus NRRL B 1865.


Asunto(s)
Cromatografía en Capa Delgada/métodos , Nigericina/análogos & derivados , Nigericina/análisis , Streptomyces/análisis , Calibración , Ionización de Llama , Lípidos/análisis , Piranos/análisis
3.
Chem Pharm Bull (Tokyo) ; 39(3): 607-11, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2070441

RESUMEN

The structure of WS1279, isolated from Streptomyces sp. as an immunoactive lipopeptide, has been deduced on the basis of chemical and physical evidence as S-[2,3-bis(palmitoyloxy)propyl]-N alpha-palmitoyl-Cys-Asn-Ser-Gly-Gly-Ser- OH. This was confirmed by synthesis.


Asunto(s)
Lipoproteínas/química , Secuencia de Aminoácidos , Lipoproteínas/síntesis química , Datos de Secuencia Molecular , Streptomyces/análisis
4.
Agric Biol Chem ; 55(2): 407-17, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1368692

RESUMEN

C-1027-AG, a selective antagonist of antitumor antibiotic C-1027, was isolated by column chromatography on DEAE-cellulose, butyl-Toyopearl and Sephadex G-50 from a culture filtrate of Streptomyces globisporus. The amino acid sequence of purified C-1027-AG was determined with a protein sequencer on the basis of fragment peptides obtained by enzymatic hydrolysis with lysylendopeptidase, V8 protease, endopeptidase AspN and chymotrypsin, after performic acid oxidation. C-1027-AG is shown to consist of a single polypeptide chain cross-linked by two disulfide bonds, and to contain a total of 110 amino acid residues with alanine and glycine as its amino- and carboxyl-termini, respectively; its molecular weight was calculated to be 10,500 daltons. The primary structure of C-1027-AG is indicated to be identical to the protein moiety of C-1027, and is highly homologous to the sequences of antitumor proteins obtained from other Streptomyces species.


Asunto(s)
Aminoglicósidos , Antibacterianos , Proteínas/aislamiento & purificación , Streptomyces/análisis , Secuencia de Aminoácidos , Aminoácidos/análisis , Antibióticos Antineoplásicos/antagonistas & inhibidores , Enediinos , Datos de Secuencia Molecular , Proteínas/antagonistas & inhibidores , Proteínas/química
5.
Chem Biol Interact ; 79(2): 137-49, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1884427

RESUMEN

The calf thymus DNA (CT-DNA) and poly(dI-dC).poly(dI-dC) binding properties of the natural antitumor antibiotic CC-1065 and selected analogs of CC-1065 were studied by circular dichroism (CD) and absorbance methods. The results indicate that the intense long wavelength DNA-induced CD band of these molecules originates from a chiral electronic transition which is delocalized over the whole molecule. Both the covalently bound species (N-3 adenine adduct) and the reversibly bound species exhibit the characteristic spectral behavior of an inherently dissymmetric chromophore when these agents bind within the minor groove of B-form DNA. This mechanism of optical activity accounts for why CC-1065 shows a weak CD in buffer but a very intense induced CD at long wavelength when bound to DNA, why the intensity of the induced CD of CC-1065 analogs depends upon how many fused ring systems the analog contains, and why covalently bound analogs having the mirror image configuration of the natural configuration also exhibit an intense positive induced CD band at long wavelength.


Asunto(s)
Antibióticos Antineoplásicos/química , Dicroismo Circular , ADN/farmacología , Indoles , Leucomicinas/química , Sitios de Unión , Duocarmicinas , Conformación Molecular , Streptomyces/análisis
6.
Rev. argent. micol ; 14(2): 27-32, 1991. ilus
Artículo en Español | LILACS | ID: lil-105662

RESUMEN

Se presenta un caso de artritis de rodilla por Streptomyces somaliensis, raro agente causal de micetomas, que predomina en el continente africano. Es el segundo caso encontrado en la Argentina, con aislamiento e identificación microbiológica del agente causal y el único donde se demostró compromiso intra-articular


Asunto(s)
Actinomicosis/diagnóstico , Artritis Infecciosa/etiología , Rodilla , Traumatismos de la Rodilla/complicaciones , Streptomyces/aislamiento & purificación , Actinomycetales/análisis , Actinomycetales/aislamiento & purificación , Actinomycetales/metabolismo , Actinomicosis/patología , Actinomicosis/terapia , Argentina , Artritis Infecciosa/patología , Enfermedad Crónica , Micetoma/complicaciones , Streptomyces/análisis , Streptomyces/metabolismo
7.
FEBS Lett ; 277(1-2): 137-40, 1990 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-2176611

RESUMEN

Tautomycin inhibited the catalytic subunits of protein phosphatase-1 (Kiapp = 0.16 nM) more potently than protein phosphatase 2A (Kiapp = 0.4 nM), and the native forms of these enzymes in mammalian, protozoan and plant extracts were inhibited in a similar manner. Protein phosphatase 2B was inhibited 10,000-fold less potently, while two other phosphatases and six protein kinases were unaffected at 10 microM. Okadaic acid prevented the binding of tautomycin to protein phosphatase 2A, indicating a common binding site for both inhibitors. The different relative potencies of tautomycin and okadaic acid for protein phosphatases 1 and 2A suggest that parallel use of both inhibitors may help to identify physiological substrates for each enzyme.


Asunto(s)
Fosfoproteínas Fosfatasas/antagonistas & inhibidores , Piranos , Compuestos de Espiro , Streptomyces/análisis , Antifúngicos/farmacología , Éteres Cíclicos/farmacología , Técnicas In Vitro , Cinética , Toxinas Marinas , Microcistinas , Ácido Ocadaico , Péptidos Cíclicos/farmacología , Fosforilasas/metabolismo , Proteína Fosfatasa 1 , Proteína Fosfatasa 2
8.
J Chromatogr ; 520: 325-31, 1990 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-2086584

RESUMEN

A procedure is described for the purification of hydrophobic microbial proteins such as streptavidin from Streptomyces avidinii, using Benzyl-DC bead cellulose as the column material. The separation is rapid with a high loading capacity and sufficient resolution for preparative uses. Advantages are discussed especially for industrial purposes.


Asunto(s)
Proteínas Bacterianas/aislamiento & purificación , Cromatografía de Afinidad/métodos , Cromatografía por Intercambio Iónico/métodos , Estreptavidina , Streptomyces/análisis , Streptomyces/citología
9.
J Biochem ; 108(2): 158-65, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2229019

RESUMEN

The three-dimensional structure of an alpha-amylase inhibitor, HAIM, composed of 78 amino acids, was analyzed by two-dimensional NMR techniques. Sequence-specific assignments were made for the amino acid residues from Ile-6 to Cys-72. Distance geometry analysis of the interresidue NOEs revealed that the HAIM molecule consists of two beta-sheets, as is the case in a homologous alpha-amylase inhibitor, Tendamistat, though one of its beta-strands is much shorter than that of Tendamistat. The combination of molecular modeling from Tendamistat and distance geometry analysis was confirmed to be useful for our purpose.


Asunto(s)
Proteínas Bacterianas/química , alfa-Amilasas/antagonistas & inhibidores , Secuencia de Aminoácidos , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Modelos Químicos , Datos de Secuencia Molecular , Péptidos/química , Conformación Proteica , Streptomyces/análisis
10.
Biochemistry ; 29(24): 5676-81, 1990 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-2383554

RESUMEN

Leinamycin is a recently discovered antitumor antibiotic with an unusual 1,3-dioxo-1,2-dithiolane structure. It preferentially inhibits the incorporation of [3H]thymidine into the acid-insoluble fraction of Bacillus subtilis. In vitro, leinamycin causes single-strand cleavage of supercoiled double-helical pBR322 DNA in the presence of thiol cofactors. Scavengers of oxygen radical did not supress the DNA-cleaving activity. Thiol-activated leinamycin binds calf thymus DNA at 4 degrees C and thermal treatment of the leinamycin-DNA adduct released a chemically modified leinamycin from the complex. The lack of cytotoxicity and DNA-cleaving activity for S-deoxyleinamycin indicates that the 1,3-dioxo-1,2-dithiolane moiety is essential for the activity of leinamycin. Thus, the primary cellular target of leinamycin appears to be DNA. It binds DNA and causes single-strand break at low concentrations, which may account for the potent antitumor activity.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , ADN Bacteriano/efectos de los fármacos , Lactamas , Streptomyces/análisis , Tiazoles , Tionas , Antibióticos Antineoplásicos/aislamiento & purificación , Bacillus/efectos de los fármacos , Bacillus/genética , Bacillus/crecimiento & desarrollo , Daño del ADN , ADN Bacteriano/biosíntesis , ADN de Cadena Simple/biosíntesis , ADN de Cadena Simple/efectos de los fármacos , Ditiotreitol/farmacología , Macrólidos
11.
Eur J Biochem ; 190(2): 263-71, 1990 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-2142075

RESUMEN

The sequence-specific resonance assignment of apo-neocarzinostatin from Streptomyces carzinostaticus was carried out from two-dimensional proton-NMR spectra. The assignments were obtained for the backbone protons of 111 of the 113 residues of the protein, missing the two C alpha H of one glycine but including 3 of the 4 prolines. The majority of side chain protons were also assigned. The secondary structure derived from the analysis of sequential connections corresponds to ten beta-strands separated by clearly identified loops and turns. Inter-strand connectivities and slowly exchanging amide protons confirm the presence of the two disulfide bridges from Cys37 to Cys47 and from Cys88 to Cys93 and indicate a global folding similar to that of the similar proteins, actinoxanthin and macromomycin, for which crystallographic data are available.


Asunto(s)
Antibióticos Antineoplásicos/aislamiento & purificación , Streptomyces/análisis , Cinostatina/aislamiento & purificación , Alanina , Secuencia de Aminoácidos , Aminoácidos/análisis , Glicina , Leucina , Espectroscopía de Resonancia Magnética/métodos , Datos de Secuencia Molecular , Conformación Proteica , Soluciones , Treonina , Valina
12.
FASEB J ; 4(2): 222-6, 1990 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-2153594

RESUMEN

A computer-based comparison of the amino acid sequences of human placental 17 beta-hydroxysteroid dehydrogenase and Streptomyces coelicolor actIII protein, which is important in the synthesis of the antibiotic actinorhodin, gives an alignment score 12.15 standard deviations higher than that of 1000 comparisons of randomized sequences of these proteins. The probability of getting this score by chance is 3 x 10(-34). Comparison of actIII protein with Drosophila melanogaster alcohol dehydrogenase yields a score of 10.3 standard deviations (P = 3.5 x 10(-25)). Based on these similarities, we propose that 17 beta-hydroxysteroid dehydrogenase, actIII protein, and Drosophila alcohol dehydrogenase are derived from a common ancestor.


Asunto(s)
17-Hidroxiesteroide Deshidrogenasas , Alcohol Deshidrogenasa , Oxidorreductasas de Alcohol , Proteínas Bacterianas , Drosophila melanogaster/enzimología , Placenta/enzimología , Streptomyces/análisis , Secuencia de Aminoácidos , Animales , Evolución Biológica , Femenino , Humanos , Datos de Secuencia Molecular , Embarazo , Homología de Secuencia de Ácido Nucleico
13.
J Antibiot (Tokyo) ; 43(2): 129-34, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2155895

RESUMEN

Resorthiomycin, a novel antitumor antibiotic, was isolated from the fermentation broth of a strain of Streptomyces collinus by ethyl acetate extraction, silica gel chromatography and HPLC. Resorthiomycin exhibited an in vitro cytotoxic activity against mouse leukemia L5178Y cells (IC50, 15.5 micrograms/ml) and also inhibited the clonogenic activity of a multidrug-resistant mutant of human hepatoma PLC/PRF/5 cells to a greater extent than that of the parental cells. On the other hand, this antibiotic does not possess any antibacterial or antifungal activity.


Asunto(s)
Antibióticos Antineoplásicos/aislamiento & purificación , Animales , Carcinoma Hepatocelular , Línea Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Humanos , Leucemia L5178 , Neoplasias Hepáticas , Ratones , Resorcinoles/aislamiento & purificación , Resorcinoles/farmacología , Streptomyces/análisis
14.
J Antibiot (Tokyo) ; 43(2): 168-73, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2312405

RESUMEN

RK-286C, a new inhibitor of protein kinase C, has been found by the bleb-forming assay using K562 cells. It was produced by Streptomyces sp. RK-286 and purified by solvent extraction, silica gel chromatography and preparative HPLC. Spectrometric analysis revealed that the structure is 4'-demethylamino-4'-hydroxystaurosporine.


Asunto(s)
Alcaloides/aislamiento & purificación , Proteína Quinasa C/antagonistas & inhibidores , Alcaloides/análisis , Fenómenos Químicos , Química Física , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Medios de Cultivo/análisis , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Espectrofotometría , Estaurosporina/análogos & derivados , Streptomyces/análisis
15.
J Antibiot (Tokyo) ; 43(2): 143-8, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1968900

RESUMEN

Probestin has been isolated as part of a program designed to find microorganism-produced inhibitors of aminopeptidase M from Streptomyces azureus MH663-2F6. It was purified by use of column chromatography of Amberlite XAD-4, silica gel, YMC-gel, Toyopearl HW-40, YMC D-ODS-5 (HPLC) and then isolated as colorless powders. Probestin is competitive with the substrate, and the inhibition constant (Ki) of it was 1.9 x 10(-8) M.


Asunto(s)
Aminopeptidasas/antagonistas & inhibidores , Oligopéptidos/aislamiento & purificación , Streptomyces/análisis , Animales , Antígenos CD13 , Fenómenos Químicos , Química Física , Medios de Cultivo/análisis , Cinética , Ratones , Oligopéptidos/farmacología , Oligopéptidos/toxicidad
16.
J Antibiot (Tokyo) ; 43(2): 149-53, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1968901

RESUMEN

Probestin, a new inhibitor of aminopeptidase M, has been isolated from the culture broth of Streptomyces azureus MH663-2F6. The 1H and 13C NMR studies and amino acid analysis confirmed the presence of one 3-amino-2-hydroxy-phenylbutanoic acid, leucine and two proline residues in the molecule. Stereochemistries of these amino acids were determined by HPLC analysis. The fragmentation pattern shown in the mass spectrum and the chemical analysis on probestin clarified the amino acid sequence. Thus the structure of probestin was defined as (2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl-L-leucyl-L-prolyl-L-pro line.


Asunto(s)
Aminopeptidasas/antagonistas & inhibidores , Oligopéptidos/análisis , Streptomyces/análisis , Secuencia de Aminoácidos , Aminoácidos/análisis , Antígenos CD13 , Cromatografía Líquida de Alta Presión , Medios de Cultivo/análisis , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Datos de Secuencia Molecular , Oligopéptidos/farmacología
17.
Folia Microbiol (Praha) ; 35(2): 172-5, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2379888

RESUMEN

Analytical and preparative high-performance liquid chromatography of 3 phenazines and furonaphthoquinone derivative on reversed-phase column are described. The mobile phase was methanol and water. The injected amount of the mixture was about 30 mg for a preparative chromatographic run requiring 80 min. Substances were detected directly in the column effluent by UV detection.


Asunto(s)
Cromatografía Líquida de Alta Presión , Fenazinas/aislamiento & purificación , Streptomyces/análisis , Furanos/aislamiento & purificación , Naftoquinonas/aislamiento & purificación
18.
J Antibiot (Tokyo) ; 42(12): 1734-40, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2621156

RESUMEN

Two novel antibiotics, glucopiericidinols A1 (1) and A2 (2) were isolated from the cultured broth of Streptomyces sp. OM-5689. The structures of these two compounds were deduced employing spectroscopic analyses. These antibiotics showed potent cytocidal activities against HeLa S3 cells in vitro (MIC 1: 0.39 microgram/ml, 2: 0.10 microgram/ml) when the cells were exposed to the antibiotics for 3 days. Although 1 and 2 showed no activity at 1,000 micrograms/ml against various Gram-positive and Gram-negative bacteria, yeast or fungi, they did have inhibitory activity against Piricularia oryzae (MIC of 1: 125 micrograms/ml, of 2: 31 micrograms/ml).


Asunto(s)
Aminoglicósidos , Antibacterianos/aislamiento & purificación , Piridinas/aislamiento & purificación , Antibacterianos/farmacología , Fenómenos Químicos , Química , Fermentación , Pruebas de Sensibilidad Microbiana , Streptomyces/análisis
19.
J Antibiot (Tokyo) ; 42(12): 1768-74, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2621160

RESUMEN

Leinamycin (DC 107) is newly discovered antitumor antibiotic with an unusual 1,3-dioxo-1,2-dithiolane structure. Five different producing strains were isolated from soils collected in Japan during 1985-1988 and were taxonomically assigned as Streptomyces. Fermentation studies indicate: Leinamycin was unstable in culture broth. A chemically defined medium could be designed for a preferable production. Streptomyces sp. S-140 grew on medium supplemented with Zn2+ and high porus polymer resin and accumulated 32 micrograms/ml of leinamycin. Improved isolation methods are described along with identification of mikamycin A co-produced with leinamycin by the strain S-140.


Asunto(s)
Antibióticos Antineoplásicos/aislamiento & purificación , Lactamas , Tiazoles , Tionas , Cromatografía Líquida de Alta Presión , Fermentación , Macrólidos , Streptomyces/análisis
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