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1.
Biochim Biophys Acta ; 1074(2): 237-42, 1991 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-1648397

RESUMO

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.


Assuntos
Parede Celular/química , Lipopolissacarídeos/isolamento & purificação , Streptomyces/análise , Ácidos Teicoicos/isolamento & purificação , Sequência de Carboidratos , Glicosídeos/isolamento & purificação , Hidrólise , Lipopolissacarídeos/química , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Monoéster Fosfórico Hidrolases , Polímeros/isolamento & purificação , Ácidos Teicoicos/química
2.
J Chromatogr ; 547(1-2): 411-8, 1991 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-1894724

RESUMO

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.


Assuntos
Cromatografia em Camada Fina/métodos , Nigericina/análogos & derivados , Nigericina/análise , Streptomyces/análise , Calibragem , Ionização de Chama , Lipídeos/análise , Piranos/análise
3.
Chem Pharm Bull (Tokyo) ; 39(3): 607-11, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2070441

RESUMO

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.


Assuntos
Lipoproteínas/química , Sequência de Aminoácidos , Lipoproteínas/síntese química , Dados de Sequência Molecular , Streptomyces/análise
4.
Agric Biol Chem ; 55(2): 407-17, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1368692

RESUMO

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.


Assuntos
Aminoglicosídeos , Antibacterianos , Proteínas/isolamento & purificação , Streptomyces/análise , Sequência de Aminoácidos , Aminoácidos/análise , Antibióticos Antineoplásicos/antagonistas & inibidores , Enedi-Inos , Dados de Sequência Molecular , Proteínas/antagonistas & inibidores , Proteínas/química
5.
Chem Biol Interact ; 79(2): 137-49, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1884427

RESUMO

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.


Assuntos
Antibióticos Antineoplásicos/química , Dicroísmo Circular , DNA/farmacologia , Indóis , Leucomicinas/química , Sítios de Ligação , Duocarmicinas , Conformação Molecular , Streptomyces/análise
6.
Rev. argent. micol ; 14(2): 27-32, 1991. ilus
Artigo em Espanhol | LILACS | ID: lil-105662

RESUMO

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


Assuntos
Actinomicose/diagnóstico , Artrite Infecciosa/etiologia , Joelho , Traumatismos do Joelho/complicações , Streptomyces/isolamento & purificação , Actinomycetales/análise , Actinomycetales/isolamento & purificação , Actinomycetales/metabolismo , Actinomicose/patologia , Actinomicose/terapia , Argentina , Artrite Infecciosa/patologia , Doença Crônica , Micetoma/complicações , Streptomyces/análise , Streptomyces/metabolismo
7.
FEBS Lett ; 277(1-2): 137-40, 1990 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-2176611

RESUMO

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.


Assuntos
Fosfoproteínas Fosfatases/antagonistas & inibidores , Piranos , Compostos de Espiro , Streptomyces/análise , Antifúngicos/farmacologia , Éteres Cíclicos/farmacologia , Técnicas In Vitro , Cinética , Toxinas Marinhas , Microcistinas , Ácido Okadáico , Peptídeos Cíclicos/farmacologia , Fosforilases/metabolismo , Proteína Fosfatase 1 , Proteína Fosfatase 2
8.
J Chromatogr ; 520: 325-31, 1990 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-2086584

RESUMO

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.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Cromatografia de Afinidade/métodos , Cromatografia por Troca Iônica/métodos , Estreptavidina , Streptomyces/análise , Streptomyces/citologia
9.
J Biochem ; 108(2): 158-65, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2229019

RESUMO

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.


Assuntos
Proteínas de Bactérias/química , alfa-Amilases/antagonistas & inibidores , Sequência de Aminoácidos , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Modelos Químicos , Dados de Sequência Molecular , Peptídeos/química , Conformação Proteica , Streptomyces/análise
10.
Eur J Biochem ; 190(2): 263-71, 1990 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-2142075

RESUMO

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.


Assuntos
Antibióticos Antineoplásicos/isolamento & purificação , Streptomyces/análise , Zinostatina/isolamento & purificação , Alanina , Sequência de Aminoácidos , Aminoácidos/análise , Glicina , Leucina , Espectroscopia de Ressonância Magnética/métodos , Dados de Sequência Molecular , Conformação Proteica , Soluções , Treonina , Valina
11.
Biochemistry ; 29(24): 5676-81, 1990 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-2383554

RESUMO

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.


Assuntos
Antibióticos Antineoplásicos/farmacologia , DNA Bacteriano/efeitos dos fármacos , Lactamas , Streptomyces/análise , Tiazóis , Tionas , Antibióticos Antineoplásicos/isolamento & purificação , Bacillus/efeitos dos fármacos , Bacillus/genética , Bacillus/crescimento & desenvolvimento , Dano ao DNA , DNA Bacteriano/biossíntese , DNA de Cadeia Simples/biossíntese , DNA de Cadeia Simples/efeitos dos fármacos , Ditiotreitol/farmacologia , Macrolídeos
12.
J Antibiot (Tokyo) ; 43(2): 143-8, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1968900

RESUMO

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.


Assuntos
Aminopeptidases/antagonistas & inibidores , Oligopeptídeos/isolamento & purificação , Streptomyces/análise , Animais , Antígenos CD13 , Fenômenos Químicos , Físico-Química , Meios de Cultura/análise , Cinética , Camundongos , Oligopeptídeos/farmacologia , Oligopeptídeos/toxicidade
13.
J Antibiot (Tokyo) ; 43(2): 149-53, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1968901

RESUMO

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.


Assuntos
Aminopeptidases/antagonistas & inibidores , Oligopeptídeos/análise , Streptomyces/análise , Sequência de Aminoácidos , Aminoácidos/análise , Antígenos CD13 , Cromatografia Líquida de Alta Pressão , Meios de Cultura/análise , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Dados de Sequência Molecular , Oligopeptídeos/farmacologia
14.
J Antibiot (Tokyo) ; 43(2): 129-34, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2155895

RESUMO

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.


Assuntos
Antibióticos Antineoplásicos/isolamento & purificação , Animais , Carcinoma Hepatocelular , Linhagem Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Humanos , Leucemia L5178 , Neoplasias Hepáticas , Camundongos , Resorcinóis/isolamento & purificação , Resorcinóis/farmacologia , Streptomyces/análise
15.
FASEB J ; 4(2): 222-6, 1990 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-2153594

RESUMO

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.


Assuntos
17-Hidroxiesteroide Desidrogenases , Álcool Desidrogenase , Oxirredutases do Álcool , Proteínas de Bactérias , Drosophila melanogaster/enzimologia , Placenta/enzimologia , Streptomyces/análise , Sequência de Aminoácidos , Animais , Evolução Biológica , Feminino , Humanos , Dados de Sequência Molecular , Gravidez , Homologia de Sequência do Ácido Nucleico
16.
J Antibiot (Tokyo) ; 43(2): 168-73, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2312405

RESUMO

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.


Assuntos
Alcaloides/isolamento & purificação , Proteína Quinase C/antagonistas & inibidores , Alcaloides/análise , Fenômenos Químicos , Físico-Química , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Meios de Cultura/análise , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Espectrofotometria , Estaurosporina/análogos & derivados , Streptomyces/análise
17.
Folia Microbiol (Praha) ; 35(2): 172-5, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2379888

RESUMO

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.


Assuntos
Cromatografia Líquida de Alta Pressão , Fenazinas/isolamento & purificação , Streptomyces/análise , Furanos/isolamento & purificação , Naftoquinonas/isolamento & purificação
18.
J Antibiot (Tokyo) ; 42(12): 1734-40, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2621156

RESUMO

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).


Assuntos
Aminoglicosídeos , Antibacterianos/isolamento & purificação , Piridinas/isolamento & purificação , Antibacterianos/farmacologia , Fenômenos Químicos , Química , Fermentação , Testes de Sensibilidade Microbiana , Streptomyces/análise
19.
J Antibiot (Tokyo) ; 42(12): 1768-74, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2621160

RESUMO

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.


Assuntos
Antibióticos Antineoplásicos/isolamento & purificação , Lactamas , Tiazóis , Tionas , Cromatografia Líquida de Alta Pressão , Fermentação , Macrolídeos , Streptomyces/análise
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