Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Syst Evol Microbiol ; 51(Pt 4): 1511-1520, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11491353

RESUMO

A bacterial strain, JG07T, isolated from the Korean traditional fermented seafood jeotgal, was subjected to a polyphasic taxonomic study. Cells of strain JG07T are cocci or short rods in the early growth phase but change to rods as the cultures age. The peptidoglycan type is A4alpha, based on L-Lys-D-Glu. The menaquinone profile is characterized by the predominance of MK-8 followed by MK-7 and MK-6. The cellular fatty acid profile contains major amounts of saturated, unsaturated and branched fatty acids. The cellular phospholipids are phosphatidylethanolamine, phosphatidylglycerol and bisphosphatidylglycerol. The G+C content of the DNA is 47 mol%. Phylogenetic analysis showed that strain JG07T forms a cluster with Planococcus okeanokoites and Planococcus mcmeekinii, and the relationship between this cluster and two other Planococcus species described previously is supported by bootstrap analysis at a confidence level of 100%. The 16S-23S internally transcribed spacer (ITS) sequence similarity and DNA-DNA relatedness values between strain JG07T and the type strains of other Planococcus species are in the range 74.6-83.2% and 10.4-20.5%, respectively. On the basis of the phenotypic and phylogenetic data and the genomic distinctiveness, strain JG07T is considered to represent a new genus and a new species, for which the name Planomicrobium koreense gen. nov., sp. nov. is proposed. It is also proposed that Planococcus okeanokoites and Planococcus mcmeekinii be transferred to the new genus Planomicrobium as Planomicrobium okeanokoites and Planomicrobium mcmeekinii, respectively.


Assuntos
Bacillaceae/classificação , Bacillaceae/isolamento & purificação , Alimentos Marinhos/microbiologia , Bacillaceae/genética , Bacillaceae/metabolismo , Composição de Bases , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Ácidos Graxos/análise , Coreia (Geográfico) , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Filogenia
2.
Planta Med ; 67(6): 585-7, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11509991

RESUMO

The 8-O-acetyl-3,10-dihydroxy-4(15),11(13)-guaiadien-12,6-olide, named borenolide, was isolated from Chrysanthemum boreale M. Borenolide inhibits the etoposide-induced apoptosis in U937 cell with an IC(50) value of 6.2 microg/ml. Structural assignment was based on NMR-spectroscopic methods and X-ray crystallographic analysis.


Assuntos
Apoptose/efeitos dos fármacos , Asteraceae/química , Sesquiterpenos/isolamento & purificação , Cristalografia por Raios X , Humanos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Conformação Molecular , Caules de Planta/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Células U937
3.
Int J Syst Evol Microbiol ; 51(Pt 3): 1079-1086, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11411676

RESUMO

A light-orange-coloured, facultatively anaerobic, rod-shaped bacterium (strain SW28T), which was isolated from seawater in Korea, was taxonomically studied by a polyphasic approach. This organism formed round terminal endospores in swollen sporangia. The peptidoglycan type is A4alpha, based on L-Lys-L-Ala-D-Asp. The predominant menaquinone is MK-7 and the major fatty acid is ante-C15:0. The G+C content of the DNA is 40 mol%. Phylogenetic analysis based on 16S rDNA sequences showed that strain SW28T falls within the radiation of a cluster comprising the rRNA group 2 bacilli and non-Bacillus-type organisms. Strain SW28T showed the highest degree of relatedness to the type strain of Sporosarcina ureae, sharing 96.8% 16S rDNA similarity. Levels of DNA-DNA relatedness between strain SW28T and S. ureae DSM 2281T and the type strains of some Bacillus species forming a coherent phylogenetic cluster are less than 12.5%. On the basis of phenotypic and chemotaxonomic characteristics, 16S rDNA sequence analysis and DNA-DNA relatedness data, it is proposed that strain SW28T should be placed in the genus Sporosarcina as a new species, Sporosarcina aquimarina sp. nov. The type strain is SW28T (= KCCM 41039T = JCM 10887T). From the results of the taxonomic re-evaluation, it is also proposed that Bacillus globisporus, Bacillus psychrophilus and Bacillus pasteurii be transferred to the genus Sporosarcina as Sporosarcina globispora, Sporosarcina psychrophila and Sporosarcina pasteurii, respectively.


Assuntos
Bacillaceae/classificação , Bacillus/classificação , Bacillus/genética , Filogenia , Bacillaceae/genética , Bacillaceae/isolamento & purificação , Bacillus/isolamento & purificação , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/análise , Coreia (Geográfico) , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Água do Mar/microbiologia
4.
Int J Syst Evol Microbiol ; 51(Pt 3): 1087-1092, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11411677

RESUMO

Two Gram-variable, rod-shaped, endospore-forming bacterial strains, which are motile with peritrichous flagella, were isolated from a Korean traditional fermented seafood, jeotgal. The two isolates (strains YKJ-1OT and YKJ-11) were proven to be members of the same species on the basis of the results of phenotypic and phylogenetic analyses and DNA relatedness. Strains YKJ-10T and YKJ-11 were characterized by having cell wall peptidoglycan based on meso-diaminopimelic acid, MK-7 as the predominant menaquinone, and iso-C15:0 as the major fatty acid. The G+C content of the DNA was 41 mol%. Strains YKJ-10T and YKJ-11 showed only a 1 bp sequence difference in the 16S rDNA sequences. The two strains formed distinct phylogenetic lineages within the radiation of the cluster comprising Bacillus species. Levels of 16S rDNA similarity between strains YKJ-10T and YKJ-11 and Bacillus species were less than 96.6%. Levels of DNA-DNA relatedness were found to be low enough to distinguish strains YKJ-10T and YKJ-11 from some phylogenetically related Bacillus species. On the basis of phenotypic properties, phylogeny and genomic distinctiveness, strains YKJ-10T and YKJ-11 represent a new species of the genus Bacillus, for which a new name, Bacillusjeotgali sp. nov., is proposed. The type strain of the new species is strain YKJ-10T (= KCCM 41040T = JCM 10885T).


Assuntos
Bacillus/classificação , Filogenia , Alimentos Marinhos/microbiologia , Bacillus/genética , Bacillus/isolamento & purificação , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/análise , Fermentação , Manipulação de Alimentos , Coreia (Geográfico) , Dados de Sequência Molecular , Fenótipo , RNA Ribossômico 16S/genética , Especificidade da Espécie
5.
Int J Syst Evol Microbiol ; 51(Pt 3): 1171-1177, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11411685

RESUMO

A halophilic Gram-negative bacterial strain, SW32T, which was isolated from a sample from the Yellow Sea of Korea, was subjected to a polyphasic taxonomic study. This organism grew optimally in the presence of 0.5-12% NaCl. On the basis of phenotypic and phylogenetic data, strain SW32T appeared to be a member of the genus Halomonas. Strain SW32T formed a distinct evolutionary lineage within the phylogenetic clade comprising Halomonas species and the genera Zymobacter and Carnimonas. The 16S rDNA sequence of strain SW32T contains 19 signature characteristics of the genus Halomonas and the family Halomonadaceae. Strain SW32T possessed a single polar flagellum, ubiquinone-9 as the predominant respiratory lipoquinone and C18:1, C16:0 and C16:1 omega7c and/or iso-C15:0 20H as the major fatty acids. The DNA G+C content was 59 mol%. Levels of 16S rDNA similarity between strain SW32T and the type strains of all validly described Halomonas species were 92.0-93.8%. Strain SW32T exhibited 16S rDNA similarity values of 92.7% to Zymobacter palmae IAM 14233T and 91.6% to Carnimonas nigrificans CECT 4437T. These data indicate that strain SW32T was related enough to members of the genus Halomonas to be placed as a new species within that genus. Therefore the name Halomonas marisflavae sp. nov. is proposed for strain SW32T. The type strain of the new species is strain SW32T (= KCCM 80003T = JCM 10873T).


Assuntos
Halomonas/classificação , Filogenia , DNA Ribossômico/genética , Halomonas/genética , Halomonas/isolamento & purificação , Halomonas/ultraestrutura , Coreia (Geográfico) , Microscopia Eletrônica , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Ubiquinona/metabolismo
6.
Pharm World Sci ; 23(1): 17-21, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11344586

RESUMO

Chronic inflammatory bowel disease (IBD) refers to two diseases: Crohn's disease (CD) and ulcerative colitis (UC). The etiology of IBD remains unknown. The understanding of the pathogenesis has expanded greatly over the last decade. The combination of genetic risk factors, abnormalities in the immune system, vascular and neural factors, and random environmental factors may all play an important role. Most treatments currently in use have multiple action. The choice of appropriate medical treatment is determined by the status (inductive or maintenance therapy) and severity of the disease and the potential for toxicity. Despite the variety of medical therapies available for the treatment of IBD, none is ideal. Ongoing research into the well-established drugs, as well as novel agents with more precise targets, may contribute to an optimal therapy of IBD in the near future. In this paper the current (5-aminosalicylates, glucocorticosteroids, thioguanine derivatives, methotrexate, cyclosporin and infliximab) as well as some of the new (mycophenolate mofetil and thalidomide) therapeutic options are reviewed.


Assuntos
Fármacos Gastrointestinais/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Animais , Humanos , Doenças Inflamatórias Intestinais/epidemiologia , Doenças Inflamatórias Intestinais/patologia , Fatores de Risco
8.
Int J Syst Evol Microbiol ; 50 Pt 5: 1789-1795, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11034488

RESUMO

A bacteriocin-producing lactic acid bacterium, which was isolated from the Korean fermented-vegetable food kimchi, was subjected to a polyphasic taxonomic study using phenotypic characterization and phylogenetic and genetic methods. This organism (MT-1077T) has phenotypic properties that are consistent with the description characterizing the genus Lactobacillus. Phylogenetic analysis based on 16S rDNA sequences showed clearly that strain MT-1077T is a member of the genus Lactobacillus. The closest phylogenetic relatives are Lactobacillus alimentarius KCTC 3593T and Lactobacillus farciminis LMG 9200T, with levels of 16S rDNA similarity of 98.4 and 98.2%, respectively. Levels of 16S rDNA similarity between strain MT-1077T and other Lactobacillus species were less than 93.0%. Differences in some phenotypic characteristics and DNA-DNA relatedness data indicated that strain MT-1077T should be distinguished from L. alimentarius KCTC 3593T and L. farciminis LMG 9200T. On the basis of the data presented, it is proposed that strain MT-1077T should be placed in the genus Lactobacillus as a new species, Lactobacillus kimchii sp. nov. The type strain of the new species is strain MT-1077T (= KCTC 8903PT = JCM 10707T).


Assuntos
Microbiologia de Alimentos , Lactobacillus/classificação , Lactobacillus/genética , Verduras/microbiologia , Técnicas de Tipagem Bacteriana , Bacteriocinas/biossíntese , Composição de Bases , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/análise , DNA Ribossômico/genética , Ácidos Graxos/análise , Fermentação , Coreia (Geográfico) , Lactobacillus/química , Lactobacillus/fisiologia , Dados de Sequência Molecular , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
9.
Int J Syst Evol Microbiol ; 50 Pt 5: 1821-1827, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11034493

RESUMO

A bacterial strain, CS12T, which was isolated from soil around a wastewater treatment plant, was subjected to a polyphasic taxonomic study using phenotypic characterizations and genetic methods. The cell wall of strain CS12T contains meso-diaminopimelic acid as the diamino acid but no arabinose and galactose. The predominant menaquinone is MK-8(H4). Mycolic acids are absent. Strain CS12T has a cellular fatty acid profile containing saturated, unsaturated, branched and 10-methyl fatty acids. The major fatty acids are iso-C16:0, C18:1 omega9c and anteiso-C17:0, The G+C content is 69 mol%. A phylogenetic tree based on 16S rDNA sequences showed that strain CS12T forms an evolutionary lineage within the radiation enclosing the members of the family Intrasporangiaceae and, in particular, a coherent cluster with Janibacter limosus DSM 11140T. The level of 16S rDNA similarity between strain CS12T and J. limosus DSM 11140T is 98.7%. The phenotypic characteristics and DNA-DNA relatedness data indicate that strain CS12T should be distinguished from J. limosus DSM 11140T. Therefore, on the basis of the data presented, a new species of the genus Janibacter, Janibacter terrae, is proposed. The type strain of the new species is strain CS12T (= KCCM 80001T = JCM 10705T).


Assuntos
Actinomycetales/classificação , Microbiologia do Solo , Eliminação de Resíduos Líquidos , Actinomycetales/genética , Actinomycetales/isolamento & purificação , Actinomycetales/fisiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Ribossômico/análise , DNA Ribossômico/genética , Ácidos Graxos/análise , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
11.
Int J Syst Evol Microbiol ; 50 Pt 6: 2173-2180, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11155994

RESUMO

The taxonomic position of a bacterial strain (PDB9T) that is capable of degrading pyridine was clarified by a polyphasic taxonomic approach using phenotypic, chemotaxonomic and genetic methods. The cells, which are rods and branched filaments during the early growth phase, fragment into short rods or cocci, thereby completing the growth cycle. Strain PDB9T was found to have a cell wall of chemotype IV, MK-8(H2) as the predominant menaquinone, mycolic acids with 36-46 carbon atoms and C16:0' C18:1 cis9, 10-methyl-C18:0 (TBSA) as the major fatty acids. The G+C content of the DNA was 66 mol%. The phylogenetic tree showed that strain PDB9T falls within an evolutionary radiation comprising Rhodococcus species and is most closely related to the type strain of Rhodococcus rhodochrous, sharing 99% 16S rDNA similarity. The differences in some phenotypic characteristics and the genetic distinctiveness distinguish strain PDB9T from the Rhodococcus species described previously. Therefore, strain PDB9T should be placed in the genus Rhodococcus as a new species, for which the new name Rhodococcus pyridinivorans sp. nov. is proposed. The type strain of the new species is strain PDB9T (= KCTC 0647BPT = KCCM 80005T).


Assuntos
Piridinas/metabolismo , Rhodococcus/classificação , DNA Ribossômico/análise , Ácidos Graxos/análise , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Rhodococcus/química , Rhodococcus/genética , Rhodococcus/fisiologia , Análise de Sequência de DNA
13.
J Antibiot (Tokyo) ; 50(6): 469-73, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9268001

RESUMO

New melanin synthesis inhibitors (MR566A and B) and six related known isocyanocyclopentenes were isolated from the fermentation broth of Trichoderma harzianum. The IC50 values of MR566A and B against mushroom tyrosinase were 1.72 and 47 microM, respectively. They inhibited melanin biosynthesis in B16 melanoma cells with MIC values of 0.1 and 2.2 microM, respectively. Also isolated from the same culture extract of T. harzianum was a new oxazole (MR93B), which showed no inhibitory activity against mushroom tyrosinase at a concentration of 1,000 microg/ml.


Assuntos
Ciclopentanos/metabolismo , Melaninas/biossíntese , Nitrilas/metabolismo , Trichoderma/classificação , Trichoderma/metabolismo , Animais , Basidiomycota/enzimologia , Ciclopentanos/isolamento & purificação , Ciclopentanos/farmacologia , Inibidores Enzimáticos/farmacologia , Fermentação , Melaninas/antagonistas & inibidores , Melanoma Experimental/metabolismo , Camundongos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Nitrilas/isolamento & purificação , Nitrilas/farmacologia , Streptomyces/efeitos dos fármacos , Streptomyces/metabolismo , Trichoderma/química , Células Tumorais Cultivadas/efeitos dos fármacos
14.
J Antibiot (Tokyo) ; 50(6): 474-8, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9268002

RESUMO

New melanin synthesis inhibitors (MR566A and B) and six related known isocyanocyclopentenes were isolated from the fermentation broth of Trichoderma harzianum, and their structures were elucidated by spectroscopic methods. The structures of novel isocyanides, MR566A (1) and B (2), were elucidated as 1-(3-chloro-1,2-dihydroxy-4-isocyano-4-cyclopenten-1-yl)etha nol, 1-(1,2,3-trihydroxy-3-isocyano-4-cyclopenten-1-yl)ethanol, respectively. The structure of novel oxazole, MR93B (9), was elucidated as 4-[(1Z)-3-hydroxy-2-hydroxymethyl-1-propen-1-yl]oxazole.


Assuntos
Ciclopentanos/química , Melaninas/biossíntese , Nitrilas/química , Trichoderma/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Melaninas/antagonistas & inibidores , Melaninas/química , Conformação Molecular , Estereoisomerismo
16.
Curr Biol ; 6(6): 695-706, 1996 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-8793296

RESUMO

BACKGROUND: Synaptic contacts between neurons and their targets are dynamic entities that can change depending on developmental and functional states of the pre- and postsynaptic cell. However, the molecular factors involved in this plasticity have remained largely unknown. We have demonstrated previously that the Drosophila tumor suppressor gene, discs-large (dlg), is expressed at neuromuscular synapses, and is required for normal synapse structure. A family of dlg homologues is also expressed at mammalian synapses, where they interact with the N-methyl-D-aspartate receptor and ion channels. Here, we provide the first demonstration of the involvement of dlg in structural synaptic plasticity during postsynaptic target growth. RESULTS: We used a temperature-sensitive dlg allele to demonstrate that there are two stages, late embryogenesis and larval stages, at which dlg is necessary for normal formation of synapses. These stages are coincident with dynamic DLG expression at presynaptic sites in the late embryo, and at postsynaptic regions in the larva. Ultrastructural and confocal analyses reveal that Drosophila neuromuscular junctions undergo a dramatic expansion of the postsynaptic apparatus, which is paralleled by target muscle growth. We show that this process of postsynaptic expansion is partially blocked in dlg mutants. CONCLUSIONS: Our results demonstrate that dlg is required during synapse maturation. We show that dlg is involved in the determination of postsynaptic size during target muscle growth. Because motoneuron targets in the larva are continuously growing, synaptic contacts are structurally plastic, undergoing continuous expansion. We conclude that dlg plays an important role in this form of structural synaptic plasticity.


Assuntos
Proteínas de Drosophila , Drosophila/genética , Genes Supressores de Tumor , Ácido Glutâmico/metabolismo , Hormônios de Inseto/genética , Plasticidade Neuronal/fisiologia , Sinapses/metabolismo , Proteínas Supressoras de Tumor , Animais , Drosophila/embriologia , Drosophila/fisiologia , Expressão Gênica , Larva , Mutação , Terminações Pré-Sinápticas
17.
Biosci Biotechnol Biochem ; 60(5): 898-900, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8704320

RESUMO

A bestatin analogue, (2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl-L-valine (AHPA-Val), from the culture filtrate of Streptomyces neyagawaensis SL-387 was obtained in a chemically defined medium containing DL-3-amino-3-phenylpropionic acid. AHPA-Val was 6 times (IC50 = 1.2 micrograms/ml) as strong as bestatin (IC50 = 7.0 micrograms/ml) against porcine kidney microsomal aminopeptidase N, and 4 times (5.6 micrograms/ml) as strong as bestatin (IC50 = 20.7 micrograms/ml) against aminopeptidase N of human metastatic fibrosarcoma HT1080. To the best of our knowledge, this is the first report on the microbial production of AHPA-Val.


Assuntos
Aminopeptidases/antagonistas & inibidores , Leucina/análogos & derivados , Inibidores de Proteases/metabolismo , Streptomyces/metabolismo , Aminoácidos/química , Antígenos CD13 , Humanos , Leucina/química , Leucina/metabolismo , Espectroscopia de Ressonância Magnética , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Valina/química
20.
Biochim Biophys Acta ; 1202(2): 200-6, 1993 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-7691184

RESUMO

Raw-starch-digesting amylase (RSDA) is a key extracellular enzyme of mesophilic Bacillus circulans F-2 which uses raw starch granules as a carbon source. Previous work has demonstrated that there are two domains of the enzyme during digestion with subtilisin, and that RSDA activity is selectively inactivated by limited proteolysis with subtilisin, which cleaves the enzyme between these hydrolytic and adsorption domains (Kim, C.-H., Kwon, S.-T., Taniguchi, H. and Lee, D.-S. (1992) Biochim. Biophys. Acta 1122, 243-250). In this work we show that a similar phenomenon is observed during limited proteinase K, thermolysin and endopeptidase Glu-C proteolysis of the enzyme. Fragments resulting from proteolysis were characterized by immunoblotting with anti-RSDA. The proteolytic patterns resulting from proteinase K and subtilisin were the same, producing 63 and 30-kDa fragments. Similar patterns were obtained with endopeptidase Glu-C or thermolysin. All proteolytic digests contained a common, major 63-kDa fragment. Inactivation of RSDA activity results from splitting off the C-terminal domain. Hence, it seems probable that the proteinase-sensitive locus is in a hinge region susceptible to cleavage. Extracellular enzymes immunoreactive towards anti-RSDA were detected through whole bacterial cultivation. 93, 75, 63, 55, 38 and 31-kDa proteins were immunologically identical to RSDA. Of these, the 75-kDa and 63-kDa proteins correspond to the major products of proteolysis with Glu-C and thermolysin. These results suggest that enzyme heterogeneity of the raw-starch hydrolysis system might arise from the endogenous proteolytic activity of the bacterium.


Assuntos
Amilases/química , Bacillus/enzimologia , Amilases/metabolismo , Endopeptidase K , Peso Molecular , Fragmentos de Peptídeos/química , Serina Endopeptidases , Amido/metabolismo , Termolisina
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...