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1.
J Antibiot (Tokyo) ; 54(8): 628-34, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11592499

ABSTRACT

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.


Subject(s)
Fermentation , Fungi/metabolism , Indoles , Indoles/blood , Promoter Regions, Genetic , Simian virus 40/genetics , Transcription Factors/biosynthesis , Transcription Factors/chemistry , Chemical Phenomena , Chemistry, Physical , Chromatography, High Pressure Liquid , Enhancer Elements, Genetic , HeLa Cells , Humans , Indoles/chemistry , Indoles/pharmacology , Magnetic Resonance Spectroscopy , Molecular Structure , Spectrum Analysis , Transcription Factors/pharmacology , Transcription, Genetic/drug effects , Transfection
2.
J Mol Biol ; 311(3): 543-8, 2001 Aug 17.
Article in English | MEDLINE | ID: mdl-11493007

ABSTRACT

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.


Subject(s)
Cysteine Endopeptidases/chemistry , Cysteine Endopeptidases/metabolism , Cysteine Proteinase Inhibitors/chemistry , Cysteine Proteinase Inhibitors/metabolism , Multienzyme Complexes/chemistry , Multienzyme Complexes/metabolism , Peptides, Cyclic/chemistry , Peptides, Cyclic/metabolism , Saccharomyces cerevisiae/enzymology , Antibiotics, Antineoplastic/chemistry , Antibiotics, Antineoplastic/metabolism , Binding Sites , Crystallography, X-Ray , Drug Design , Hydrogen Bonding , Models, Molecular , Multienzyme Complexes/antagonists & inhibitors , Oligopeptides/chemistry , Oligopeptides/metabolism , Proteasome Endopeptidase Complex , Protein Conformation , Protein Structure, Secondary , Static Electricity
3.
J Antibiot (Tokyo) ; 54(5): 421-7, 2001 May.
Article in English | MEDLINE | ID: mdl-11480885

ABSTRACT

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.


Subject(s)
Antibiotics, Antineoplastic/pharmacology , Chrysosporium/metabolism , Enzyme Inhibitors/pharmacology , Pyrans/pharmacology , cdc25 Phosphatases/antagonists & inhibitors , Animals , Biological Assay , Cell Division/drug effects , Chrysosporium/growth & development , Humans , Hydrogenation , Inhibitory Concentration 50 , Leukemia P388/drug therapy , Melanoma, Experimental/drug therapy , Mice , Tumor Cells, Cultured , cdc25 Phosphatases/metabolism
5.
J Org Chem ; 65(4): 990-5, 2000 Feb 25.
Article in English | MEDLINE | ID: mdl-10814045

ABSTRACT

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.


Subject(s)
Cysteine Endopeptidases/metabolism , Cysteine Proteinase Inhibitors/chemistry , Fungi/chemistry , Multienzyme Complexes/metabolism , Peptides, Cyclic/chemistry , Cysteine Proteinase Inhibitors/pharmacology , Gas Chromatography-Mass Spectrometry , Magnetic Resonance Spectroscopy , Models, Molecular , Molecular Structure , Peptides, Cyclic/pharmacology , Proteasome Endopeptidase Complex , Protein Conformation
6.
J Antibiot (Tokyo) ; 53(2): 105-9, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10805568

ABSTRACT

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.


Subject(s)
Cysteine Endopeptidases/drug effects , Mitosporic Fungi/classification , Mitosporic Fungi/metabolism , Multienzyme Complexes/drug effects , Peptides, Cyclic/pharmacology , Protease Inhibitors/isolation & purification , Protease Inhibitors/pharmacology , Chymotrypsin/metabolism , Colonic Neoplasms/drug therapy , Fermentation , HL-60 Cells/drug effects , Humans , Hydrolysis , Inhibitory Concentration 50 , Peptides/metabolism , Peptides, Cyclic/isolation & purification , Peptides, Cyclic/metabolism , Protease Inhibitors/metabolism , Proteasome Endopeptidase Complex , Trypsin/metabolism , Tumor Cells, Cultured
8.
Surg Today ; 30(1): 43-8, 2000.
Article in English | MEDLINE | ID: mdl-10648082

ABSTRACT

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).


Subject(s)
Thymoma/pathology , Thymus Gland/pathology , Thymus Neoplasms/pathology , Epithelial Cells/pathology , Female , Humans , Male , Middle Aged , Myasthenia Gravis/etiology , Myasthenia Gravis/pathology , Neoplasm Staging , Prognosis , Survival Rate , Thymoma/classification , Thymus Neoplasms/classification
12.
J Antibiot (Tokyo) ; 52(12): 1069-76, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10695669

ABSTRACT

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.


Subject(s)
Actinomycetales/metabolism , Cysteine Endopeptidases/drug effects , Dipeptides/isolation & purification , Multienzyme Complexes/drug effects , Protease Inhibitors/isolation & purification , Streptomyces/metabolism , Animals , Dipeptides/pharmacology , Fermentation , Humans , Mice , Protease Inhibitors/pharmacology , Proteasome Endopeptidase Complex , Streptomyces/classification
13.
J Antibiot (Tokyo) ; 52(12): 1114-23, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10695675

ABSTRACT

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.


Subject(s)
Anti-Bacterial Agents/isolation & purification , Mitosporic Fungi/metabolism , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Mannose/analogs & derivatives , Mannose/chemistry , Mannose/isolation & purification , Mannose/pharmacology , Molecular Conformation , Waxes/chemistry , Waxes/isolation & purification , Waxes/pharmacology
14.
Carbohydr Res ; 306(3): 349-60, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9648245

ABSTRACT

(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.


Subject(s)
Aminoglycosides , Anti-Bacterial Agents/chemical synthesis , Dibekacin/analogs & derivatives , Dibekacin/toxicity , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/chemical synthesis , Carbohydrate Sequence , Dibekacin/chemical synthesis , Dibekacin/pharmacology , Magnetic Resonance Spectroscopy , Molecular Sequence Data , Molecular Structure , Stereoisomerism , Structure-Activity Relationship
15.
Int Orthop ; 22(6): 397-9, 1998.
Article in English | MEDLINE | ID: mdl-10093810

ABSTRACT

We describe a case of rheumatoid arthritis (RA) with collapse of the L3 lumbar vertebra for which surgery was performed. The pathogenesis of lumbar lesions affected by RA is discussed and the literature reviewed.


Subject(s)
Arthritis, Rheumatoid/complications , Fractures, Spontaneous/etiology , Lumbar Vertebrae/injuries , Spinal Fractures/etiology , Biopsy , Female , Fractures, Spontaneous/diagnosis , Fractures, Spontaneous/surgery , Humans , Magnetic Resonance Imaging , Middle Aged , Myelography , Spinal Fractures/diagnosis , Spinal Fractures/surgery , Spinal Fusion , Tomography, X-Ray Computed , Treatment Outcome
16.
J Antibiot (Tokyo) ; 49(12): 1212-20, 1996 Dec.
Article in English | MEDLINE | ID: mdl-9031666
18.
Biosci Biotechnol Biochem ; 60(6): 1036-7, 1996 Jun.
Article in English | MEDLINE | ID: mdl-8695905

ABSTRACT

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.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antiviral Agents/pharmacology , Borates/pharmacology , HIV-1/drug effects , HIV-2/drug effects , 1-Deoxynojirimycin/analogs & derivatives , Anti-Bacterial Agents/chemistry , Antiviral Agents/chemistry , Borates/chemistry , Cell Line , Dextran Sulfate/pharmacology , Glucosamine/analogs & derivatives , Glucosamine/pharmacology , Glycoside Hydrolases/antagonists & inhibitors , HIV Reverse Transcriptase , Humans , Molecular Structure , RNA-Directed DNA Polymerase/drug effects , RNA-Directed DNA Polymerase/metabolism , Streptomyces/metabolism
20.
J Dermatol ; 22(7): 496-9, 1995 Jul.
Article in English | MEDLINE | ID: mdl-7560440

ABSTRACT

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.


Subject(s)
Graft vs Host Disease/genetics , Transplantation Chimera , Adult , Bone Marrow Transplantation , Graft vs Host Disease/pathology , Humans , Male , Skin/pathology
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