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1.
Nutrients ; 16(8)2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38674937

RESUMEN

Osteoporosis, a disease defined by the primary bone strength due to a low bone mineral density, is a bone disorder associated with increased mortality in the older adult population. Osteoporosis is mainly treated via hormone replacement therapy, bisphosphates, and anti-bone resorption agents. However, these agents exert severe side effects, necessitating the development of novel therapeutic agents. Many studies are focusing on osteogenic agents as they increase the bone density, which is essential for osteoporosis treatment. Here, we aimed to investigate the effects of Diospyros lotus L. leaf extract (DLE) and its components on osteoporosis in MC3T3-E1 pre-osteoblasts and ovariectomized mice and to elucidate the underlying related pathways. DLE enhanced the differentiation of MC3T3-E1 pre-osteoblasts, with a 1.5-fold elevation in ALP activity, and increased the levels of osteogenic molecules, RUNX family transcription factor 2, and osterix. This alteration resulted from the activation of bone morphogenic protein 2/4 (BMP2/4) and transformation of growth factor ß (TGF ß) pathways. In ovariectomized mice, DLE suppressed the decrease in bone mineral density by 50% and improved the expression of other bone markers, which was confirmed by the 3~40-fold increase in osteogenic proteins and mRNA expression levels in bone marrow cells. The three major compounds identified in DLE exhibited osteogenic and estrogenic activities with their aglycones, as previously reported. Among the major compounds, myricitrin alone was not as strong as whole DLE with all its constituents. The osteogenic activity of DLE was partially suppressed by the inhibitor of estrogen signaling, indicating that the estrogenic activity of DLE participated in its osteogenic activity. Overall, DLE suppresses osteoporosis by inducing osteoblast differentiation.


Asunto(s)
Densidad Ósea , Proteína Morfogenética Ósea 2 , Diferenciación Celular , Diospyros , Osteoblastos , Osteogénesis , Ovariectomía , Extractos Vegetales , Hojas de la Planta , Transducción de Señal , Factor de Crecimiento Transformador beta , Animales , Extractos Vegetales/farmacología , Proteína Morfogenética Ósea 2/metabolismo , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteogénesis/efectos de los fármacos , Femenino , Ratones , Hojas de la Planta/química , Densidad Ósea/efectos de los fármacos , Factor de Crecimiento Transformador beta/metabolismo , Diospyros/química , Diferenciación Celular/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Osteoporosis/tratamiento farmacológico , Osteoporosis/prevención & control , Proteína Morfogenética Ósea 4/metabolismo
2.
Front Plant Sci ; 14: 1250906, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37868322

RESUMEN

The genus Streptomyces has been unceasingly highlighted for the versatility and diversity of the antimicrobial agents they produce. Moreover, it is a heavily sequenced taxon in the phylum Actinobacteria. In this study, 47 sequence profiles were identified as proteins highly conserved within the genus Streptomyces. Significant hits to the 38 profiles were found in more than 2000 Streptomyces genomes, 11 of which were further conserved in more than 90% of Actinobacterial genomes analyzed. Only a few genes corresponding to these sequence profiles were functionally characterized, which play regulatory roles in the morphology and biosynthesis of antibiotics. Here a highly conserved sequence, namely, SHC-AMP (Streptomyces highly conserved antimicrobial peptide), which exhibited antimicrobial activity against bacterial and fungal plant pathogens, was reported. In particular, Arabidopsis thaliana was effectively protected against infection with Pseudomonas syringae pv. tomato DC3000 by treatment with this peptide. Results indicated the potential application of this peptide as an antimicrobial agent for control of plant diseases. Our results suggest putative target genes for controlling Streptomyces spp., including the one exhibiting antimicrobial activity against a wide range of phytopathogens.

3.
Front Plant Sci ; 13: 837020, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35360322

RESUMEN

Gray mold disease is one of the most frequently occurring diseases in strawberries. Given that it spreads rapidly, rapid countermeasures are necessary through the development of early diagnosis technology. In this study, hyperspectral images of strawberry leaves that were inoculated with gray mold fungus to cause disease were taken; these images were classified into healthy and infected areas as seen by the naked eye. The areas where the infection spread after time elapsed were classified as the asymptomatic class. Square regions of interest (ROIs) with a dimensionality of 16 × 16 × 150 were acquired as training data, including infected, asymptomatic, and healthy areas. Then, 2D and 3D data were used in the development of a convolutional neural network (CNN) classification model. An effective wavelength analysis was performed before the development of the CNN model. Further, the classification model that was developed with 2D training data showed a classification accuracy of 0.74, while the model that used 3D data acquired an accuracy of 0.84; this indicated that the 3D data produced slightly better performance. When performing classification between healthy and asymptomatic areas for developing early diagnosis technology, the two CNN models showed a classification accuracy of 0.73 with regards to the asymptomatic ones. To increase accuracy in classifying asymptomatic areas, a model was developed by smoothing the spectrum data and expanding the first and second derivatives; the results showed that it was possible to increase the asymptomatic classification accuracy to 0.77 and reduce the misclassification of asymptomatic areas as healthy areas. Based on these results, it is concluded that the proposed 3D CNN classification model can be used as an early diagnosis sensor of gray mold diseases since it produces immediate on-site analysis results of hyperspectral images of leaves.

4.
Sci Rep ; 9(1): 13533, 2019 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-31537850

RESUMEN

Despite the efficacy of synthetic fungicides in controlling postharvest diseases, public concerns regarding chemical residues in food and an increase in drug-resistant strains of pathogens have led to a need for new agents to control postharvest diseases. The current study was performed to find control agents of microbial origin that are effective on gray mold of tomato fruits. We recently isolated Streptomyces rectiviolaceus DY46, which has antagonistic activity against various plant pathogenic fungi. The incidence of gray mold of tomato fruits was markedly reduced by 80.0% in tomatoes treated with the cell extract of Streptomyces rectiviolaceus DY46 compared with the control tomatoes. The active ingredient was purified from the cell extract of DY46 and identified to be 32,33-didehydroroflamycoin (DDHR). DDHR displayed MICs (minimal inhibitory concentrations) against the mycelial growth of various plant pathogenic fungi at concentrations of 8-64 mg L-1. The incidence of gray mold in tomato fruits inoculated with conidial suspension (104 conidia mL-1) of Botrytis cinerea was markedly reduced by 88.9% in tomatoes treated with DDHR (100 mg L-1) compared with the control. The DDHR residue in tomato fruit was significantly diminished 2 d after treatment. These results show that DDHR would be relatively safe for use as a postharvest fungicide.


Asunto(s)
Botrytis/efectos de los fármacos , Filipina/análogos & derivados , Fungicidas Industriales/metabolismo , Filipina/metabolismo , Frutas/microbiología , Hongos/efectos de los fármacos , Solanum lycopersicum/microbiología , Enfermedades de las Plantas/microbiología , Esporas Fúngicas/efectos de los fármacos , Streptomyces/metabolismo
5.
Sensors (Basel) ; 19(11)2019 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-31181613

RESUMEN

Phosphate is a key element affecting plant growth. Therefore, the accurate determination of phosphate concentration in hydroponic nutrient solutions is essential for providing a balanced set of nutrients to plants within a suitable range. This study aimed to develop a data fusion approach for determining phosphate concentrations in a paprika nutrient solution. As a conventional multivariate analysis approach using spectral data, partial least squares regression (PLSR) and principal components regression (PCR) models were developed using 56 samples for calibration and 24 samples for evaluation. The R2 values of estimation models using PCR and PLSR ranged from 0.44 to 0.64. Furthermore, an estimation model using raw electromotive force (EMF) data from cobalt electrodes gave R2 values of 0.58-0.71. To improve the model performance, a data fusion method was developed to estimate phosphate concentration using near infrared (NIR) spectral and cobalt electrochemical data. Raw EMF data from cobalt electrodes and principle component values from the spectral data were combined. Results of calibration and evaluation tests using an artificial neural network estimation model showed that R2 = 0.90 and 0.89 and root mean square error (RMSE) = 96.70 and 119.50 mg/L, respectively. These values are sufficiently high for application to measuring phosphate concentration in hydroponic solutions.

6.
Proteins ; 85(1): 117-124, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27802586

RESUMEN

The heart-specific isoform of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB2) is an important regulator of glycolytic flux in cardiac cells. Here, we present the crystal structures of two PFKFB2 orthologues, human and bovine, at resolutions of 2.0 and 1.8 Å, respectively. Citrate, a TCA cycle intermediate and well-known inhibitor of PFKFB2, co-crystallized in the 2-kinase domains of both orthologues, occupying the fructose-6-phosphate binding-site and extending into the γ-phosphate binding pocket of ATP. This steric and electrostatic occlusion of the γ-phosphate site by citrate proved highly consequential to the binding of co-complexed ATP analogues. The bovine structure, which co-crystallized with ADP, closely resembled the overall structure of other PFKFB isoforms, with ADP mimicking the catalytic binding mode of ATP. The human structure, on the other hand, co-complexed with AMPPNP, which, unlike ADP, contains a γ-phosphate. The presence of this γ-phosphate made adoption of the catalytic ATP binding mode impossible for AMPPNP, forcing the analogue to bind atypically with concomitant conformational changes to the ATP binding-pocket. Inhibition kinetics were used to validate the structural observations, confirming citrate's inhibition mechanism as competitive for F6P and noncompetitive for ATP. Together, these structural and kinetic data establish a molecular basis for citrate's negative feed-back loop of the glycolytic pathway via PFKFB2. Proteins 2016; 85:117-124. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Adenosina Difosfato/química , Adenosina Trifosfato/química , Ácido Cítrico/química , Fructosafosfatos/química , Isoenzimas/química , Miocardio/química , Fosfofructoquinasa-2/química , Adenosina Difosfato/metabolismo , Adenosina Trifosfato/metabolismo , Adenilil Imidodifosfato/química , Adenilil Imidodifosfato/metabolismo , Animales , Sitios de Unión , Bovinos , Ácido Cítrico/metabolismo , Clonación Molecular , Cristalografía por Rayos X , Escherichia coli/genética , Escherichia coli/metabolismo , Fructosafosfatos/metabolismo , Expresión Génica , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Cinética , Modelos Moleculares , Miocardio/enzimología , Fosfofructoquinasa-2/genética , Fosfofructoquinasa-2/metabolismo , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Estructura Secundaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidad de la Especie , Especificidad por Sustrato
7.
Pest Manag Sci ; 72(8): 1529-36, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26518268

RESUMEN

BACKGROUND: Endophytic bacteria are viewed as a potential new source of biofungicides because they have beneficial characteristics as control agents for plant disease. This study was performed to examine the endophytic feature and disease control efficacy of Bacillus amyloliquefaciens strain GYL4 and to identify the antifungal compounds produced by this strain. RESULTS: B. amyloliquefaciens strain GYL4 was isolated from leaf tissue of pepper plants (Capsicum annuum L.). Anthracnose symptoms were markedly reduced in the leaves of pepper plants colonised by GYL4. An egfp-expressing strain of GYL4 (GYL4-egfp) was constructed and reintroduced into pepper plants, which confirmed its ability to colonise the internal tissues of pepper plants. GYL4-egfp was observed in the root and stem tissues 4 days after treatment and abundantly found in the internal leaf tissue 9 days after treatment. Bacillomycin derivatives purified from the culture extract of GYL4 displayed control efficacy on anthracnose development in cucumber (Cucumis sativus L. cv. Chunsim). CONCLUSION: The present study is the first report on evaluation of the endophytic and systemic nature of B. amyloliquefaciens strain GYL4 and its potential as a biocontrol agent for anthracnose management. © 2015 Society of Chemical Industry.


Asunto(s)
Bacillus amyloliquefaciens/química , Agentes de Control Biológico/química , Capsicum/microbiología , Enfermedades de las Plantas/microbiología , Bacillus amyloliquefaciens/metabolismo , Agentes de Control Biológico/metabolismo , Cucumis sativus/microbiología , Endófitos/química , Endófitos/metabolismo , Enfermedades de las Plantas/prevención & control
9.
J Gen Appl Microbiol ; 59(4): 279-85, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24005177

RESUMEN

Current studies of the antioxidant activity of fungal resources are mainly focused on the fruiting bodies of edible mushrooms. To access the potential of basidiomycetes in culture-state applications, extracts of solid cultures of 83 basidiomycetous fungi newly isolated from woody materials were prepared at the same concentration (10 mg/ml), and their antioxidant activities were measured using ABTS (2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical-scavenging assays. Among the basidiomycetes tested, Cryptoporus volvatus, Daedalea dickinsii, Gloeophyllum abietinum, G. trabeum, Pseudomerulius curtisii and Stereum hirsutum exhibited good antioxidant activities. The EC50 value for the removal of free radicals was lowest (i.e., most effective) in the crude extract of S. sanguinolentum (19.61 g/ml), and reduced DNA damage based on a DNA nicking assay was observed for the extracts from the six basidiomycetous species above.


Asunto(s)
Antioxidantes/aislamiento & purificación , Basidiomycota/química , Basidiomycota/crecimiento & desarrollo , Antioxidantes/metabolismo , Benzotiazoles/metabolismo , Compuestos de Bifenilo/metabolismo , Medios de Cultivo/química , Picratos/metabolismo , Ácidos Sulfónicos/metabolismo
10.
J Basic Microbiol ; 53(7): 581-9, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22915202

RESUMEN

Microbial culture extracts are used for natural product screening to find antifungal lead compounds. A microbial culture extract library was constructed using 343 actinomycete isolates to examine the value of the adenylate kinase (AK) assay for screening to identify antifungal metabolites that disrupt cell integrity in plant pathogenic fungi. A culture extract of Streptomyces sp. strain KP6107 lysed cells of Fusarium oxysporum f.sp. lycopersici which resulted in high AK activity. The active ingredient N-1 was purified from the culture extract using various chromatographic procedures and identified to be the guanidyl-polyol macrolide antibiotic, niphimycin, which is a potent fungal cell membrane disruptor. Niphimycin showed broad-spectrum antifungal activity against Alternaria mali, Aspergillus oryzae, Colletotrichum coccodes, Colletotrichum gloeosporioides, Cercospora canescens, Cylindrocarpon destructans, F. oxysporum f.sp. cucumerinum, F. oxysporum f.sp. lycopersici, and Rhizoctonia solani at concentrations of 8-64 µg ml(-1). Anthracnose development in pepper plants was completely inhibited by treatment with 50 µg ml(-1) niphimycin, which was as effective as chlorothalonil. These results show that the AK assay is an efficient and selective tool in screening for cell membrane/wall disruptors of plant pathogenic fungi.


Asunto(s)
Adenilato Quinasa/química , Fungicidas Industriales/química , Ascomicetos/crecimiento & desarrollo , Bioensayo , Colletotrichum/crecimiento & desarrollo , Fungicidas Industriales/aislamiento & purificación , Fusarium/crecimiento & desarrollo , Guanidinas/química , Guanidinas/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Plantas/microbiología , Streptomyces/crecimiento & desarrollo
11.
J Basic Microbiol ; 52(2): 150-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22460913

RESUMEN

A number of bacterial strains were isolated from the internal tissue of Trapa japonica. Of these, strain KPE62302H, which had a 16S rDNA sequence identical to that of Streptomyces miharaensis showed antifungal activity against several plant pathogens. Treatment of seeds with strain KPE62302H induced a significant reduction in the incidence of Fusarium wilt in tomato plants compared with untreated controls. An antifungal substance (FP-1) was purified from the culture extract of strain KPE62302H using C18 flash and Sephadex LH-20 column chromatography and reverse phase HPLC. Extensive spectrometric analysis using MS and NMR identified this as filipin III. FP-1 inhibited the mycelial growth of plant pathogenic fungi such as Alternaria mali, Aspergillus niger, Colletotrichum gloeosporioides, C. orbiculare, Cylindrocarpon destructans, Diaporthe citiri, Fusarium oxysporum at 1-10 µg ml(-1) and also markedly inhibited the development of Fusarium wilt caused by F. oxysporum f.sp. lycopersici in tomato plants by treatment with 10 µg ml(-1) under greenhouse conditions. The efficacy of FP-1 against Fusarium wilt was comparable to that of the synthetic fungicide benomyl. An egfp -tagged strain of KPE62302H confirmed its ability to colonize tomato plants.


Asunto(s)
Agentes de Control Biológico , Filipina/farmacología , Fusarium/patogenicidad , Enfermedades de las Plantas/prevención & control , Streptomyces/fisiología , Fungicidas Industriales/farmacología , Fusarium/efectos de los fármacos , Solanum lycopersicum/microbiología , Enfermedades de las Plantas/microbiología , Pirazoles/farmacología , ARN Ribosómico 16S/genética , Semillas/microbiología , Streptomyces/genética
12.
PLoS One ; 6(9): e24179, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21957443

RESUMEN

Cancer cells adopt glycolysis as the major source of metabolic energy production for fast cell growth. The HIF-1-induced PFKFB3 plays a key role in this adaptation by elevating the concentration of Fru-2,6-BP, the most potent glycolysis stimulator. As this metabolic conversion has been suggested to be a hallmark of cancer, PFKFB3 has emerged as a novel target for cancer chemotherapy. Here, we report that a small molecular inhibitor, N4A, was identified as an initial lead compound for PFKFB3 inhibitor with therapeutic potential. In an attempt to improve its potency, we determined the crystal structure of the PFKFB3•N4A complex to 2.4 Šresolution and, exploiting the resulting molecular information, attained the more potent YN1. When tested on cultured cancer cells, both N4A and YN1 inhibited PFKFB3, suppressing the Fru-2,6-BP level, which in turn suppressed glycolysis and, ultimately, led to cell death. This study validates PFKFB3 as a target for new cancer therapies and provides a framework for future development efforts.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Descubrimiento de Drogas/métodos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Glucólisis/efectos de los fármacos , Fosfofructoquinasa-2/antagonistas & inhibidores , Antineoplásicos/metabolismo , Benzopiranos/química , Benzopiranos/metabolismo , Benzopiranos/farmacología , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/metabolismo , Fructosafosfatos/metabolismo , Células HeLa , Humanos , Modelos Moleculares , Fosfofructoquinasa-2/química , Fosfofructoquinasa-2/metabolismo , Conformación Proteica
13.
Anal Biochem ; 418(1): 143-8, 2011 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-21771574

RESUMEN

Efforts toward improving the predictiveness in tier-based approaches to virtual screening (VS) have mainly focused on protein kinases. Despite their significance as drug targets, small molecule kinases have been rarely tested with these approaches. In this paper, we investigate the efficacy of a pharmacophore screening-combined structure-based docking approach on the human inducible 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase, an emerging target for cancer chemotherapy. Six out of a total 1364 compounds from NCI's Diversity Set II were selected as true actives via throughput screening. Using a database constructed from these compounds, five programs were tested for structure-based docking (SBD) performance, the MOE of which showed the highest enrichments and second highest screening rates. Separately, using the same database, pharmacophore screening was performed, reducing 1364 compounds to 287 with no loss in true actives, yielding an enrichment of 4.75. When SBD was retested with the pharmacophore filtered database, 4 of the 5 SBD programs showed significant improvements to enrichment rates at only 2.5% of the database, with a 7-fold decrease in an average VS time. Our results altogether suggest that combinatorial approaches of VS technologies are easily applicable to small molecule kinases and, moreover, that such methods can decrease the variability associated with single-method SBD approaches.


Asunto(s)
Bases de Datos Factuales , Ensayos Analíticos de Alto Rendimiento , Modelos Moleculares , Fosfofructoquinasa-2/antagonistas & inhibidores , Fosfofructoquinasa-2/química , Diseño de Fármacos , Humanos , Ligandos
14.
Phytopathology ; 101(6): 666-78, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21405997

RESUMEN

We previously selected rhizobacterial strains CCR04, CCR80, GSE09, ISE13, and ISE14, which were antagonistic to Phytophthora blight of pepper. In this study, we investigated the effects of root treatment of rhizobacteria on anthracnose occurrence, ripening, and yield of pepper fruit in the plastic house and field in 2008 and 2009. We also examined the effects of volatiles produced by the strains on fruit ripening and on mycelial growth and spore development of Colletotrichum acutatum and Phytophthora capsici in the laboratory, identifying the volatile compounds by gas chromatography-mass spectrometry (GC-MS). In the house tests, all strains significantly (P < 0.05) reduced anthracnose incidence on pepper fruit; strains GSE09 and ISE14 consistently produced higher numbers of pepper fruit or increased the fresh weight of red fruit more than the controls in both years. In the field tests, all strains significantly (P < 0.05) reduced anthracnose occurrence on either green or red pepper fruit; strain ISE14 consistently produced higher numbers or increased fresh weights of red fruit more than the controls in both years. In the laboratory tests, volatiles produced by strains GSE09 and ISE13 only stimulated maturation of pepper fruit from green (unripe) to red (ripe) fruit; the volatiles of certain strains inhibited the growth and development of C. acutatum and P. capsici. On the other hand, GC-MS analysis of volatiles of strains GSE09 and ISE13 revealed 17 distinct compounds in both strains, including decane, dodecane, 1,3-di-tert-butylbenzene, tetradecane, 2,4-di-tert-butylphenol, and hexadecane. Among these compounds, 2,4-di-tert-butylphenol only stimulated fruit ripening and inhibited growth and development of the pathogens. Taken together, strains GSE09 and ISE14 effectively reduced anthracnose occurrence and stimulated pepper fruit ripening and yield, possibly via bacterial volatiles. Therefore, these two strains could be potential agents for controlling Phytophthora blight and anthracnose, and for increasing fruit ripening and yield. To our knowledge, this is the first report of volatiles such as 2,4-di-tert-butylphenol produced by rhizobacteria being related to both fruit ripening and pathogen inhibition.


Asunto(s)
Capsicum/efectos de los fármacos , Capsicum/microbiología , Colletotrichum/efectos de los fármacos , Fenoles/farmacología , Phytophthora/efectos de los fármacos , Enfermedades de las Plantas/terapia , Capsicum/fisiología , Chryseobacterium/química , Chryseobacterium/metabolismo , Colletotrichum/clasificación , Colletotrichum/crecimiento & desarrollo , Colletotrichum/patogenicidad , Flavobacterium/química , Flavobacterium/metabolismo , Frutas/efectos de los fármacos , Frutas/microbiología , Frutas/fisiología , Proteínas Fúngicas/genética , Cromatografía de Gases y Espectrometría de Masas , Hifa/efectos de los fármacos , Hifa/crecimiento & desarrollo , Lysobacter/química , Lysobacter/metabolismo , Fenoles/química , Filogenia , Phytophthora/clasificación , Phytophthora/crecimiento & desarrollo , Phytophthora/patogenicidad , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/estadística & datos numéricos , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/microbiología , Raíces de Plantas/fisiología , Pseudomonas/química , Pseudomonas/metabolismo , Análisis de Secuencia de ADN , Tubulina (Proteína)/química , Tubulina (Proteína)/genética , Compuestos Orgánicos Volátiles/química , Compuestos Orgánicos Volátiles/metabolismo
15.
J Agric Food Chem ; 59(5): 1893-9, 2011 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-21314121

RESUMEN

During screening of microorganisms producing antifungal metabolites, Streptomyces psammoticus strain KP1404 was isolated. The culture extract of this strain showed potent disease control efficacy against Fusarium wilt on tomato plants. The antifungal metabolites ST-1 and ST-2 were isolated from the culture extract using a variety of chromatographic procedures. On the basis of MS and NMR spectrometric analysis, the structures of the antifungal active compounds ST-1 and ST-2 were determined to be the polyene antibiotics strevertene A and strevertene B, respectively. In vitro, strevertenes A and B showed inhibitory effects against the mycelial growth of Alternaria mali , Aspergillus oryzae , Cylindrocarpon destructans , Colletotrichum orbiculare , Fusarium oxysporum f.sp. lycopersici, and Sclerotinia sclerotiorum , even at concentrations of 4-16 µg/mL. Fusarium wilt development on tomato plants was strongly retarded by treatment with 1 µg/mL of these strevertenes. The disease control efficacies of strevertenes on Fusarium wilt were as remarkable as that of benomyl.


Asunto(s)
Fungicidas Industriales/farmacología , Fusarium/efectos de los fármacos , Enfermedades de las Plantas/prevención & control , Solanum lycopersicum/microbiología , Streptomyces/metabolismo , Microscopía Electrónica de Rastreo , Enfermedades de las Plantas/microbiología , Polienos/química , Polienos/farmacología , Streptomyces/ultraestructura
16.
Hum Mol Genet ; 20(7): 1353-62, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21233130

RESUMEN

Zfp42/Rex1 (reduced expression gene 1) is a well-known stem-cell marker that has been duplicated from YY1 in the eutherian lineage. In the current study, we characterized the in vivo roles of Rex1 using a mutant mouse line disrupting its transcription. In contrast to the ubiquitous expression of YY1, Rex1 is expressed only during spermatogenesis and early embryogenesis and also in a very limited area of the placenta. Yet, the gene dosage of Rex1 is very critical for the survival of the late-stage embryos and neonates. This delayed phenotypic consequence suggests potential roles for Rex1 in establishing and maintaining unknown epigenetic modifications. Consistently, Rex1-null blastocysts display hypermethylation in the differentially methylated regions (DMRs) of Peg3 and Gnas imprinted domains, which are known to contain YY1 binding sites. Further analyses confirmed in vivo binding of Rex1 only to the unmethylated allele of these two regions. Thus, Rex1 may function as a protector for these DMRs against DNA methylation. Overall, the functional connection of Rex1 to genomic imprinting represents another case where newly made genes have co-evolved with lineage-specific phenomena.


Asunto(s)
Alelos , Blastocisto/metabolismo , Metilación de ADN/fisiología , Impresión Genómica/fisiología , Factores de Transcripción/metabolismo , Animales , Blastocisto/citología , Cromograninas , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/metabolismo , Humanos , Factores de Transcripción de Tipo Kruppel/metabolismo , Ratones , Ratones Mutantes , Factores de Transcripción/genética
17.
Biodegradation ; 21(6): 1029-40, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20454836

RESUMEN

In this study, we isolated and characterized a novel feather-degrading bacterium that shows keratinolytic, antifungal and plant growth-promoting activities. A bacterium S8 was isolated from forest soil and confirmed to belong to Bacillus subtilis by BIOLOG system and 16S rRNA gene analysis. The improved culture conditions for the production of keratinolytic protease were 0.1% (w/v) sorbitol, 0.3% (w/v) KNO(3), 0.1% (w/v) K(2)HPO(4), 0.06% (w/v) KH(2)PO(4) and 0.04% (w/v) MgCl(2)·6H(2)O (pH 8.0 and 30°C), respectively. In the improved medium containing 0.1% (w/v) feather, keratinolytic protease production was around 53.3 ± 0.3 U/ml at 4 day; this value was 10-fold higher than the yield in the basal feather medium (5.3 ± 0.1 U/ml). After cultivation for 5 days in the improved medium, intact feather was completely degraded. Feather degradation resulted in free -SH group, soluble protein and amino acids production. The concentration of free -SH group in the culture medium was 15.5 ± 0.2 µM at 4 days. Nineteen amino acids including all essential amino acids were produced in the culture medium; the concentration of total amino acid produced was 3360.4 µM. Proline (2809.9 µM), histidine (371.3 µM) and phenylalanine (172.0 µM) were the major amino acids released in the culture medium. B. subtilis S8 showed the properties related to plant growth promotion: hydrolytic enzymes, ammonification, indoleacetic acid (IAA), phosphate solubilization, and broad-spectrum antimicrobial activity. Interestingly, the strain S8 grown in the improved medium produced IAA and antifungal activity, indicating simultaneous production of keratinolytic and antifungal activities and IAA by B. subtilis S8. These results suggest that B. subtilis S8 could be not only used to improve the nutritional value of feather wastes but also is useful in situ biodegradation of feather wastes. Furthermore, it could also be a potential biofertilizer or biocontrol agent applicable to crop plant soil.


Asunto(s)
Bacillus subtilis/aislamiento & purificación , Bacillus subtilis/metabolismo , Plumas/metabolismo , Microbiología del Suelo , Árboles/microbiología , Aminoácidos/metabolismo , Animales , Antifúngicos/farmacología , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/enzimología , Biodegradación Ambiental/efectos de los fármacos , Carbono/farmacología , Proliferación Celular/efectos de los fármacos , Pollos , Plumas/efectos de los fármacos , Plumas/ultraestructura , Concentración de Iones de Hidrógeno/efectos de los fármacos , Ácidos Indolacéticos/metabolismo , Queratinas/metabolismo , Pruebas de Sensibilidad Microbiana , Nitrógeno/farmacología , Péptido Hidrolasas/metabolismo , Sorbitol/farmacología , Temperatura , Factores de Tiempo
18.
BMC Mol Biol ; 10: 85, 2009 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-19712462

RESUMEN

BACKGROUND: The transcription factor Yin Yang 1 (YY1) is a ubiquitously expressed, multifunctional protein that controls a large number of genes and biological processes in vertebrates. As a general transcription factor, the proper levels of YY1 protein need to be maintained for the normal function of cells and organisms. However, the mechanism for the YY1 homeostasis is currently unknown. RESULTS: The current study reports that the YY1 gene locus of all vertebrates contains a cluster of its own DNA-binding sites within the 1st intron. The intact structure of these DNA-binding sites is absolutely necessary for transcriptional activity of the YY1 promoter. In an inducible cell line system that over-expresses an exogenous YY1 gene, the overall increased levels of YY1 protein caused a reduction in transcription levels of the endogenous YY1 gene. Reversion to the normal levels of YY1 protein restored the transcriptional levels of the endogenous YY1 to normal levels. This homeostatic response was also mediated through its cluster of YY1 binding sites. CONCLUSION: Taken together, the transcriptional level of YY1 is self-regulated through its internal DNA-binding sites. This study identifies YY1 as the first known autoregulating transcription factor in mammalian genomes.


Asunto(s)
Activación Transcripcional , Factor de Transcripción YY1/genética , Factor de Transcripción YY1/metabolismo , Animales , Secuencia de Bases , Sitios de Unión , Línea Celular , Evolución Molecular , Homeostasis , Humanos , Intrones , Ratones , Datos de Secuencia Molecular , Unión Proteica
19.
Nucleic Acids Res ; 37(17): 5656-64, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19628663

RESUMEN

Unusual clusters of YY1 binding sites are located within several differentially methylated regions (DMRs), including Xist, Nespas and Peg3, which all become methylated during oogenesis. In this study, we performed conditional YY1 knockdown (KD) to investigate YY1's roles in DNA methylation of these DMRs. Reduced levels of YY1 during spermatogenesis did not cause any major change in these DMRs although the same YY1 KD caused hypermethylation in these DMRs among a subset of aged mice. However, YY1 KD during oogenesis resulted in the loss of DNA methylation on Peg3 and Xist, but there were no changes on Nespas and H19. Continued YY1 KD from oogenesis to the blastocyst stage caused further loss in DNA methylation on Peg3. Consequently, high incidents of lethality were observed among embryos that had experienced the reduced levels of YY1 protein. Overall, the current study suggests that YY1 likely plays a role in the de novo DNA methylation of the DMRs of Peg3 and Xist during oogenesis and also in the maintenance of unmethylation status of these DMRs during spermatogenesis.


Asunto(s)
Metilación de ADN , Factores de Transcripción de Tipo Kruppel/genética , Oogénesis/genética , ARN no Traducido/genética , Espermatogénesis/genética , Factor de Transcripción YY1/fisiología , Animales , Blastocisto/metabolismo , Femenino , Técnicas de Silenciamiento del Gen , Células Germinativas/crecimiento & desarrollo , Factores de Transcripción de Tipo Kruppel/metabolismo , Masculino , Ratones , Ratones Transgénicos , ARN Largo no Codificante , ARN no Traducido/metabolismo , Factor de Transcripción YY1/genética
20.
Ultrasonics ; 49(6-7): 594-8, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19395053

RESUMEN

A piezoelectric motor capable of omni-directional movements has been developed to apply for robot joints, eyes, and precision positioning stage. The piezoelectric actuator has a simple structure of a cone type consisting of two piezoelectric ring-typed ceramics with electrodes divided into four segments and stainless steel elastic bodies. Before manufacturing the piezoelectric motor, the admittance characteristics and displacements of the actuator as a function of frequency were simulated. Elliptical motions of the actuator were created at several frequencies between the longitudinal and transverse resonance frequencies. The actual motor with alumina ball exhibited nice performance using a driving circuit with two rotary encoders and a PID controller. The moving element was omni-directionally operated at a driving frequency of 53.8 kHz and an output voltage of 280 V(p-p). The developed motor enables the moving element to move to a desired position with a resolution of 1.2 degrees/pulse, an angular velocity of 4 rad/s, and a thrust force of 200 g.

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