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1.
J Antibiot (Tokyo) ; 54(8): 628-34, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11592499

RESUMEN

A new transcriptional up-regulator designated TMC-205 was discovered from the fermentation broth of an unidentified fungal strain TC 1630 by using an SV40 promoter-luciferase reporter assay. Based on spectroscopic analyses, its structure was determined to be (E)-6-(3-methyl-1,3-butadienyl)- H-indole-3-carboxylic acid. Expression of the luciferase activity was activated ca. 2-, 4-, and 6-fold by 1, 10, and 100 microM TMC-205, respectively. TMC-205 activated the transcriptional activity in a manner dependent on the presence of the enhancer element of SV40 in its promoter region.


Asunto(s)
Fermentación , Hongos/metabolismo , Indoles , Indoles/sangre , Regiones Promotoras Genéticas , Virus 40 de los Simios/genética , Factores de Transcripción/biosíntesis , Factores de Transcripción/química , Fenómenos Químicos , Química Física , Cromatografía Líquida de Alta Presión , Elementos de Facilitación Genéticos , Células HeLa , Humanos , Indoles/química , Indoles/farmacología , Espectroscopía de Resonancia Magnética , Estructura Molecular , Análisis Espectral , Factores de Transcripción/farmacología , Transcripción Genética/efectos de los fármacos , Transfección
2.
J Mol Biol ; 311(3): 543-8, 2001 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-11493007

RESUMEN

The 20 S proteasome core particle (CP), a multicatalytic protease, is involved in a variety of biologically important processes, including immune response, cell-cycle control, metabolic adaptation, stress response and cell differentiation. Therefore, selective inhibition of the CP will be one possible way to influence these essential pathways. Recently, a new class of specific proteasome inhibitors, TMC-95s, was investigated and we now present a biochemical and crystallographic characterisation of the yeast proteasome core particle in complex with the natural product TMC-95A. This unusual heterocyclic compound specifically blocks the active sites of CPs non-covalently, without modifying the nucleophilic Thr1 residue. The inhibitor is bound to the CP by specific hydrogen bonds with the main-chain atoms of the protein. Analysis of the crystal structure of the complex has revealed which portions of TMC-95s are essential for binding to the proteasome. This will form the basis for the development of synthetic selective proteasome inhibitors as promising candidates for anti-tumoral or anti-inflammatory drugs.


Asunto(s)
Cisteína Endopeptidasas/química , Cisteína Endopeptidasas/metabolismo , Inhibidores de Cisteína Proteinasa/química , Inhibidores de Cisteína Proteinasa/metabolismo , Complejos Multienzimáticos/química , Complejos Multienzimáticos/metabolismo , Péptidos Cíclicos/química , Péptidos Cíclicos/metabolismo , Saccharomyces cerevisiae/enzimología , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/metabolismo , Sitios de Unión , Cristalografía por Rayos X , Diseño de Fármacos , Enlace de Hidrógeno , Modelos Moleculares , Complejos Multienzimáticos/antagonistas & inhibidores , Oligopéptidos/química , Oligopéptidos/metabolismo , Complejo de la Endopetidasa Proteasomal , Conformación Proteica , Estructura Secundaria de Proteína , Electricidad Estática
3.
J Antibiot (Tokyo) ; 54(5): 421-7, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11480885

RESUMEN

A new antibiotic designated TMC-69 has been isolated from the fermentation broth of a fungal strain Chrysosporium sp. TC 1068. TMC-69 exhibited moderate in vitro cytotoxic activity. TMC-69-6H, a derivative of TMC-69 prepared by hydrogenation, possessed more potent in vitro cytotoxicity than TMC-69, and exhibited in vivo antitumor activity against murine P388 leukemia and B16 melanoma. TMC-69-6H was found to specifically inhibit Cdc25A and B phosphatases.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Chrysosporium/metabolismo , Inhibidores Enzimáticos/farmacología , Piranos/farmacología , Fosfatasas cdc25/antagonistas & inhibidores , Animales , Bioensayo , División Celular/efectos de los fármacos , Chrysosporium/crecimiento & desarrollo , Humanos , Hidrogenación , Concentración 50 Inhibidora , Leucemia P388/tratamiento farmacológico , Melanoma Experimental/tratamiento farmacológico , Ratones , Células Tumorales Cultivadas , Fosfatasas cdc25/metabolismo
5.
J Org Chem ; 65(4): 990-5, 2000 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-10814045

RESUMEN

Four novel proteasome inhibitors, TMC-95A-D (1-4) have been isolated from the fermentation broth of Apiospora montagnei Sacc. TC 1093, isolated from a soil sample. All of the molecular formulas of 1-4 were established as C(33)H(38)N(6)O(10) by high-resolution FAB-MS. Their planar structures were determined on the basis of extensive analyses of 1D and 2D NMR, and degradation studies. Compounds 1-4 have the same planar structures to each other, and are unique highly modified cyclic peptides containing L-tyrosine, L-aspargine, highly oxidized L-tryptophan, (Z)-1-propenylamine, and 3-methyl-2-oxopentanoic acid units. The absolute configuration at C-11 and C-36 of 1-4 was determined based on chiral TLC and HPLC analyses of their chemical degradation products. The ROESY analysis along with (1)H-(1)H coupling constants clarified the absolute stereochemistry at C-6, -7, -8, and -14 of the cyclic moieties. These studies revealed the relationships of 1-4 to be diastereomers at C-7 and C-36.


Asunto(s)
Cisteína Endopeptidasas/metabolismo , Inhibidores de Cisteína Proteinasa/química , Hongos/química , Complejos Multienzimáticos/metabolismo , Péptidos Cíclicos/química , Inhibidores de Cisteína Proteinasa/farmacología , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Estructura Molecular , Péptidos Cíclicos/farmacología , Complejo de la Endopetidasa Proteasomal , Conformación Proteica
6.
J Antibiot (Tokyo) ; 53(2): 105-9, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10805568

RESUMEN

In our course of screening for novel proteasome inhibitors, TMC-95A and its diastereomers, TMC-95B to D, were isolated from the fermentation broth of Apiospora montagnei Sacc. TC 1093. TMC-95A inhibited the chymotrypsin-like (ChT-L), trypsin-like (T-L), and peptidylglutamyl-peptide hydrolyzing (PGPH) activities of 20S proteasome with IC50 values of 5.4nM, 200nM, and 60nM, respectively. TMC-95B inhibited these activities to the same extent as TMC-95A, while the inhibitory activities of TMC-95C and D were 20 to 150 times weaker than that of TMC-95A and B. TMC-95A did not inhibit m-calpain, cathepsin L, and trypsin at 30 microM, suggesting its high selectivity for proteasome. Taxonomy of the producing strain is also described.


Asunto(s)
Cisteína Endopeptidasas/efectos de los fármacos , Hongos Mitospóricos/clasificación , Hongos Mitospóricos/metabolismo , Complejos Multienzimáticos/efectos de los fármacos , Péptidos Cíclicos/farmacología , Inhibidores de Proteasas/aislamiento & purificación , Inhibidores de Proteasas/farmacología , Quimotripsina/metabolismo , Neoplasias del Colon/tratamiento farmacológico , Fermentación , Células HL-60/efectos de los fármacos , Humanos , Hidrólisis , Concentración 50 Inhibidora , Péptidos/metabolismo , Péptidos Cíclicos/aislamiento & purificación , Péptidos Cíclicos/metabolismo , Inhibidores de Proteasas/metabolismo , Complejo de la Endopetidasa Proteasomal , Tripsina/metabolismo , Células Tumorales Cultivadas
8.
Surg Today ; 30(1): 43-8, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10648082

RESUMEN

We investigated the clinicopathological correlations among 49 surgically resected thymic epithelial tumors (TET), which were subclassified according to the six subtypes established by the Marino, Kirchner, and Müller-Hermelink system, which were renamed as follows: spindle cell type (medullary thymoma), mixed spindle and polygonal cell type (mixed medullary and cortical thymoma), small polygonal cell type (predominantly cortical thymoma), large polygonal cell type (cortical thymoma), atypical type (well differentiated thymic carcinoma), and cytologically malignant type (high-grade thymic carcinoma). The related categories were grouped for statistical analysis as follows: group 1, spindle cell type and mixed type; group 2, small polygonal cell type and large polygonal cell type; group 3, atypical type; group 4, cytologically malignant type. The association of each group with the presence of myasthenia gravis, tumor stage, and the length of survival was studied. Myasthenia gravis was significantly present in patients with small polygonal type, large polygonal type, and atypical type tumors (groups 2 and 3) (P = 0.003). The tumors in group 1 showed the lowest tumor stage while those of group 4 had the most advanced tumor stage (P = 0.002). The patients in group 4 had the worst prognosis, followed by those in group 3, 2, and 1, in that order. The differences among these groups were statistically significant (P = 0.0003). From our results, we determined that TET can be separated into an extremely low-grade malignancy group (group 1), a low-grade malignancy group (group 2), an intermediate malignancy group (group 3), and a high-grade malignancy group (group 4).


Asunto(s)
Timoma/patología , Timo/patología , Neoplasias del Timo/patología , Células Epiteliales/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Miastenia Gravis/etiología , Miastenia Gravis/patología , Estadificación de Neoplasias , Pronóstico , Tasa de Supervivencia , Timoma/clasificación , Neoplasias del Timo/clasificación
12.
J Antibiot (Tokyo) ; 52(12): 1069-76, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10695669

RESUMEN

TMC-86A, B and TMC-96, new 20S proteasome inhibitors with an epoxy-beta-aminoketone moiety, were isolated from the fermentation broth of Streptomyces sp. TC 1084 and Saccharothrix sp. TC 1094, respectively. TMC-86A, B and TMC-96 inhibited the chymotrypsin-like and peptidylglutamyl-peptide hydrolyzing activities of 20S proteasome with the following IC50 values: TMC-86A, 5.1 microM and 3.7microM; TMC-86B, 1.1 microM and 31 microM; TMC-96, 2.9 microM and 3.5 microM, respectively. TMC-86A, B and TMC-96 exhibited the weak inhibitory activity against the trypsin-like activity of 20S proteasome with IC50 values of 51 microM, 250 microM, and 36 microM, respectively. They did not inhibit m-calpain, cathepsin L, and trypsin at 100 microM, suggesting their high specificity for proteasome. Taxonomy of the producing strains is also described.


Asunto(s)
Actinomycetales/metabolismo , Cisteína Endopeptidasas/efectos de los fármacos , Dipéptidos/aislamiento & purificación , Complejos Multienzimáticos/efectos de los fármacos , Inhibidores de Proteasas/aislamiento & purificación , Streptomyces/metabolismo , Animales , Dipéptidos/farmacología , Fermentación , Humanos , Ratones , Inhibidores de Proteasas/farmacología , Complejo de la Endopetidasa Proteasomal , Streptomyces/clasificación
13.
J Antibiot (Tokyo) ; 52(12): 1114-23, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10695675

RESUMEN

Four new antibiotics, TMC-171A (2), B (3), C (4) and TMC-154 (5) have been isolated from the fermentation of fungal strains Gliocladium sp. TC 1304 and TC 1282, respectively. Spectroscopic and degradation studies have shown that TMC-171s and TMC-154 were new members of the TMC-151 class of antibiotics, unique polyketides modified with a D-mannose and a D-mannitol or a D-arabitol. These compounds showed moderate cytotoxicity to various tumor cell lines.


Asunto(s)
Antibacterianos/aislamiento & purificación , Hongos Mitospóricos/metabolismo , Antibacterianos/química , Antibacterianos/farmacología , Manosa/análogos & derivados , Manosa/química , Manosa/aislamiento & purificación , Manosa/farmacología , Conformación Molecular , Ceras/química , Ceras/aislamiento & purificación , Ceras/farmacología
14.
Carbohydr Res ; 306(3): 349-60, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9648245

RESUMEN

(2S,4S)- and (2S,4R)-5-azido-2-O-benzyl-4-fluoro-2-hydroxypentanoic acids (15 and 19) have been prepared from L-malic acid (1), and coupled to the H2N-1 group of 3,2',6'-tris(N-benzyloxycarbonyl)-3"-N-(trifluoroacetyl)dibekacin (23), to give, after reduction and deblocking, 1-N-[(2S,4S)- and (2S,4R)-5-amino-4-fluoro-2-hydroxypentanoyl]dibekacins (26 and 27). The fluorinated arbekacin analogs showed almost the same antibacterial activities as that of arbekacin, but lower toxicity. Comparison of the toxicity between 26 (and 27) and the arbekacin analogs (28-30) with change of the 1N-side-chain indicates that the observed decrease in toxicity was a function of the chain length rather than the introduction of fluorine.


Asunto(s)
Aminoglicósidos , Antibacterianos/síntesis química , Dibekacina/análogos & derivados , Dibekacina/toxicidad , Antibacterianos/farmacología , Antiinfecciosos/síntesis química , Secuencia de Carbohidratos , Dibekacina/síntesis química , Dibekacina/farmacología , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Estructura Molecular , Estereoisomerismo , Relación Estructura-Actividad
16.
J Antibiot (Tokyo) ; 49(12): 1212-20, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9031666
18.
Biosci Biotechnol Biochem ; 60(6): 1036-7, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8695905

RESUMEN

The polyether-macrolide antibiotic, boromycin, was isolated as a potent anti-human immunodeficiency virus (HIV) antibiotic from a fermentation broth of Streptomyces sp. A-3376. Boromycin was found to strongly inhibit the replication of the clinically isolated HIV-1 strain as well as the cultured strain in in vitro laboratory experiments. The mechanism for the anti-HIV activity of boromycin is suggested to involve blocking the later stage of HIV infection, and probably the maturity step for replication of the HIV molecule.


Asunto(s)
Antibacterianos/farmacología , Antivirales/farmacología , Boratos/farmacología , VIH-1/efectos de los fármacos , VIH-2/efectos de los fármacos , 1-Desoxinojirimicina/análogos & derivados , Antibacterianos/química , Antivirales/química , Boratos/química , Línea Celular , Sulfato de Dextran/farmacología , Glucosamina/análogos & derivados , Glucosamina/farmacología , Glicósido Hidrolasas/antagonistas & inhibidores , Transcriptasa Inversa del VIH , Humanos , Estructura Molecular , ADN Polimerasa Dirigida por ARN/efectos de los fármacos , ADN Polimerasa Dirigida por ARN/metabolismo , Streptomyces/metabolismo
20.
J Dermatol ; 22(7): 496-9, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7560440

RESUMEN

We report a patient with graft versus host disease (GVHD) with mixed chimerism (MC). The patient had chronic myelogenous leukemia and received bone marrow transplantation (BMT) from his elder sister. Eighty days after BMT, erythematous lesions appeared on his chest. Histological examination from the skin lesion revealed lymphocytic infiltration into the upper dermis. Eosinophilic necrotic keratinocytes were scattered through the epidermis. Liquefaction degeneration was also recognized. Sicca syndrome appeared from 110 days after BMT. Detection of host origin Y-chromosome-specific DNA by polymerase chain reaction (PCR) method in bone marrow and peripheral blood showed that all bone marrow samples obtained 6 months from BMT were positive for Y-specific DNA, while peripheral blood became positive in the 60th month after BMT. The host origin normal karyotype (46,XY) in the bone marrow samples was identified for the first time in the 60th month after BMT. These results indicate that host-origin hematopoietic cells survived after BMT.


Asunto(s)
Enfermedad Injerto contra Huésped/genética , Quimera por Trasplante , Adulto , Trasplante de Médula Ósea , Enfermedad Injerto contra Huésped/patología , Humanos , Masculino , Piel/patología
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