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1.
Appl Biochem Biotechnol ; 190(2): 584-600, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31399928

RESUMO

Phellinus igniarius is a medicinal fungus that utilizes lignin as a nutrient substrate. This fungus has a weak lignin degradation ability and, as a result, a slow growth rate. Laccases are crucial enzymes for lignin degradation in P. igniarius, and thus, the cultivation of strains with high laccase activity is expected to increase the growth rate of P. igniarius. To generate P. igniarius strains with high laccase activity, we performed laser mutagenesis of P. igniarius protoplasts and screened for mutants with high laccase activity. Our results showed that the laser power density and P. igniarius protoplast survival rate exhibited a power-function relationship. The power density threshold value between lethality and growth promotion was 0.24 mW/mm2. Mutagenesis was carried out using a laser beam diameter of 3 mm and an irradiation period of 40 min. After five generations of selection, we identified a high laccase activity strain, termed SJZ2. The laccase activity in SJZ2 during 4 h of fermentation was increased by 36.84% in comparison with the control and ranged from 0.20216 to 0.27664 U. The Km and Vmax of the laccase produced by SJZ2 were 0.21 mmol/mL and 0.53 mmol/L/min, respectively. This study demonstrated the feasibility of laser mutagenesis of P. igniarius protoplasts for the selection of high laccase activity. This study characterized the key factors in the laser mutagenesis process of P. igniarius protoplasts and provided a reference for the application of lasers in biological mutagenesis. Future studies should evaluate the bioactive functionality and stability of this novel strain of P. igniarius, particularly the organoleptic and medical characteristics of the fruiting bodies.

2.
Sci Adv ; 5(11): eaav4355, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31700996

RESUMO

Recently, several captivating topological structures of electric dipole moments (e.g., vortex, flux closure) have been reported in ferroelectrics with reduced size/dimensions. However, accurate polarization distribution of these topological ferroelectric structures has never been experimentally obtained. We precisely measure the polarization distribution of an individual ferroelectric vortex in PbTiO3/SrTiO3 superlattices at the subunit cell level by using the atomically resolved integrated differential phase contrast imaging in an aberration-corrected scanning transmission electron microscope. We find, in vortices, that out-of-plane polarization is larger than in-plane polarization, and that downward polarization is larger than upward polarization. The polarization magnitude is closely related to tetragonality. Moreover, the contribution of the Pb─O bond to total polarization is highly inhomogeneous in vortices. Our precise measurement at the subunit cell scale provides a sound foundation for mechanistic understanding of the structure and properties of a ferroelectric vortex and lattice-charge coupling phenomena in these topological ferroelectric structures.

3.
Food Res Int ; 125: 108517, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31554126

RESUMO

Volatile compounds of Lentinula edodes grown in different culture substrate (CS) formulations were analyzed to reveal (i) the relationship between volatile compound production and CS formulations, (ii) the contribution of volatile compounds to L. edodes flavor, (iii) the activities of LOX and γ-GGT enzymes, (iv) γ-GGT gene expression, and (v) the correlation between enzyme activity and volatile compound production. Our results showed that 82 kinds of volatile compounds were analyzed; 25 volatile compounds were considered key flavor components, and sulfur containing compounds, eight-carbon compounds, and aldehyde compounds also had great contributions to mushroom flavor. Bagasse could be used as a partial substitute for sawdust as a carbon source. LOX and γ-GGT activities showed a weak correlation with the volatile end products. The results indicated that the mechanisms by which CS formulations influence volatile compounds production were complex.

4.
Phys Chem Chem Phys ; 21(38): 21381-21388, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31531469

RESUMO

In multiferroics, electromagnons have been recognized as a noticeable topic due to their indispensable role in magnetoelectric, magnetodielectric, and magnetocapacitance effects. Here, the electromagnons of Bi1-xNdxFeO3 (x = 0-0.2) nanoparticles are studied via terahertz time-domain spectroscopy, and the impacts of doping concentrations on electromagnons have been discussed. We found that the electromagnons in Bi1-xNdxFeO3 nanoparticles are associated with their phase transition. The total coupling weight of electromagnons is gradually increased in polar R3c structures and then reduces in the antipolar Pbam phase, and the weight in the antipolar phase is less than that of the pure R3c phase. Interestingly, a colossal electromagnon is observed at polar-antipolar and antiferromagnetic-ferromagnetic phase boundaries. Our work offers an avenue for designing and choosing materials with better magnetodielectric and magnetocapacitance properties.

5.
Mol Biol Evol ; 36(2): 341-349, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30445640

RESUMO

The diploid D-genome lineage of the Triticum/Aegilops complex has an evolutionary history involving genomic contributions from ancient A- and B/S-genome species. We explored here the possible cytonuclear evolutionary responses to this history of hybridization. Phylogenetic analysis of chloroplast DNAs indicates that the D-genome lineage has a maternal origin of the A-genome or some other closely allied lineage. Analyses of the nuclear genome in the D-genome species Aegilops tauschii indicate that accompanying and/or following this ancient hybridization, there has been biased maintenance of maternal A-genome ancestry in nuclear genes encoding cytonuclear enzyme complexes (CECs). Our study provides insights into mechanisms of cytonuclear coevolution accompanying the evolution and eventual stabilization of homoploid hybrid species. We suggest that this coevolutionary process includes likely rapid fixation of A-genome CEC orthologs as well as biased retention of A-genome nucleotides in CEC homologs following population level recombination during the initial generations.


Assuntos
Aegilops/genética , Coevolução Biológica , Especiação Genética , Genoma de Planta , Hibridização Genética , Aegilops/citologia , Epistasia Genética , Genes de Cloroplastos , Filogenia
6.
ACS Nano ; 12(9): 9558-9567, 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30138564

RESUMO

The ability to electrically write magnetic bits is highly desirable for future magnetic memories and spintronic devices, though fully deterministic, reversible, and nonvolatile switching of magnetic moments by electric field remains elusive despite extensive research. In this work, we develop a concept to electrically switch magnetization via polarization modulated oxygen vacancies, and we demonstrate the idea in a multiferroic epitaxial heterostructure of BaTiO3/Fe3O4 fabricated by pulsed laser deposition. The piezoelectricity and ferroelectricity of BaTiO3 have been confirmed by macro- and microscale measurements, for which Fe3O4 serves as the top electrode for switching the polarization. X-ray absorption spectroscopy and X-ray magnetic circular dichroism spectra indicate a mixture of Fe2+ and Fe3+ at O h sites and Fe3+ at T d sites in Fe3O4, while the room-temperature magnetic domains of Fe3O4 are revealed by microscopic magnetic force microscopy measurements. It is demonstrated that the magnetic domains of Fe3O4 can be switched by not only magnetic fields but also electric fields in a deterministic, reversible, and nonvolatile manner, wherein polarization reversal by electric field modulates the oxygen vacancy distribution in Fe3O4, and thus its magnetic state, making it attractive for electrically written magnetic memories.

7.
J Food Sci ; 83(6): 1542-1551, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29745976

RESUMO

To identify the characteristic taste components of the common cultivated mushroom (brown; Portobello), Agaricus bisporus, taste components in the stipe and pileus of Portobello mushroom harvested at different growth stages were extracted and identified, and principal component analysis (PCA) and taste active value (TAV) were used to reveal the characteristic taste components during the each of the growth stages of Portobello mushroom. In the stipe and pileus, 20 and 14 different principal taste components were identified, respectively, and they were considered as the principal taste components of Portobello mushroom fruit bodies, which included most amino acids and 5'-nucleotides. Some taste components that were found at high levels, such as lactic acid and citric acid, were not detected as Portobello mushroom principal taste components through PCA. However, due to their high content, Portobello mushroom could be used as a source of organic acids. The PCA and TAV results revealed that 5'-GMP, glutamic acid, malic acid, alanine, proline, leucine, and aspartic acid were the characteristic taste components of Portobello mushroom fruit bodies. Portobello mushroom was also found to be rich in protein and amino acids, so it might also be useful in the formulation of nutraceuticals and functional food. PRACTICAL APPLICATION: The results in this article could provide a theoretical basis for understanding and regulating the characteristic flavor components synthesis process of Portobello mushroom.


Assuntos
Agaricus/química , Análise de Alimentos , Carpóforos/química , Paladar , Aminoácidos/análise , Ácido Cítrico/análise , Proteínas na Dieta/análise , Aromatizantes , Alimento Funcional , Ácido Glutâmico/análise , Guanosina Monofosfato/análise , Humanos , Ácido Láctico/análise , Malatos/análise , Nucleotídeos/análise
8.
Plant J ; 94(6): 1141-1156, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29660196

RESUMO

The non-random spatial packing of chromosomes in the nucleus plays a critical role in orchestrating gene expression and genome function. Here, we present a Hi-C analysis of the chromatin interaction patterns in rice (Oryza sativa L.) at hierarchical architectural levels. We confirm that rice chromosomes occupy their own territories with certain preferential inter-chromosomal associations. Moderate compartment delimitation and extensive TADs (Topologically Associated Domains) were determined to be associated with heterogeneous genomic compositions and epigenetic marks in the rice genome. We found subtle features including chromatin loops, gene loops, and off-/near-diagonal intensive interaction regions. Gene chromatin loops associated with H3K27me3 could be positively involved in gene expression. In addition to insulated enhancing effects for neighbor gene expression, the identified rice gene loops could bi-directionally (+/-) affect the expression of looped genes themselves. Finally, web-interleaved off-diagonal IHIs/KEEs (Interactive Heterochromatic Islands or KNOT ENGAGED ELEMENTs) could trap transposable elements (TEs) via the enrichment of silencing epigenetic marks. In parallel, the near-diagonal FIREs (Frequently Interacting Regions) could positively affect the expression of involved genes. Our results suggest that the chromatin packing pattern in rice is generally similar to that in Arabidopsis thaliana but with clear differences at specific structural levels. We conclude that genomic composition, epigenetic modification, and transcriptional activity could act in combination to shape global and local chromatin packing in rice. Our results confirm recent observations in rice and A. thaliana but also provide additional insights into the patterns and features of chromatin organization in higher plants.


Assuntos
Montagem e Desmontagem da Cromatina/genética , Cromatina/genética , Cromossomos de Plantas/genética , Oryza/genética , Cromatina/metabolismo , Cromossomos de Plantas/fisiologia , Epigênese Genética/genética , Marcadores Genéticos/genética , Estudo de Associação Genômica Ampla
9.
Plant Physiol ; 175(3): 1082-1093, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28899963

RESUMO

The phytohormone salicylic acid (SA) plays essential roles in biotic and abiotic responses, plant development, and leaf senescence. 2,5-Dihydroxybenzoic acid (2,5-DHBA or gentisic acid) is one of the most commonly occurring aromatic acids in green plants and is assumed to be generated from SA, but the enzymes involved in its production remain obscure. DMR6 (Downy Mildew Resistant6; At5g24530) has been proven essential in plant immunity of Arabidopsis (Arabidopsis thaliana), but its biochemical properties are not well understood. Here, we report the discovery and functional characterization of DMR6 as a salicylic acid 5-hydroxylase (S5H) that catalyzes the formation of 2,5-DHBA by hydroxylating SA at the C5 position of its phenyl ring in Arabidopsis. S5H/DMR6 specifically converts SA to 2,5-DHBA in vitro and displays higher catalytic efficiency (Kcat/Km = 4.96 × 104 m-1 s-1) than the previously reported S3H (Kcat/Km = 6.09 × 103 m-1 s-1) for SA. Interestingly, S5H/DMR6 displays a substrate inhibition property that may enable automatic control of its enzyme activities. The s5h mutant and s5hs3h double mutant overaccumulate SA and display phenotypes such as a smaller growth size, early senescence, and a loss of susceptibility to Pseudomonas syringae pv tomato DC3000. S5H/DMR6 is sensitively induced by SA/pathogen treatment and is expressed widely from young seedlings to senescing plants, whereas S3H is more specifically expressed at the mature and senescing stages. Collectively, our results disclose the identity of the enzyme required for 2,5-DHBA formation and reveal a mechanism by which plants fine-tune SA homeostasis by mediating SA 5-hydroxylation.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Homeostase , Oxigenases de Função Mista/metabolismo , Ácido Salicílico/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/microbiologia , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Gentisatos/química , Gentisatos/metabolismo , Cinética , Metabolômica , Oxigenases de Função Mista/genética , Fenótipo , Plantas Geneticamente Modificadas , Pseudomonas syringae/fisiologia , Proteínas Recombinantes/metabolismo , Ácido Salicílico/química , Especificidade da Espécie , Fatores de Tempo , Transcrição Genética
10.
Sci Rep ; 7(1): 4525, 2017 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-28674444

RESUMO

Multilevel data ferroelectric tunnel junction is a breakthrough for further improving the storage density of ferroelectric random access memories. However, the application of these ferroelectric tunnel junctions is limited by high cost of epitaxial perovskite heterostructures, unsatisfactory retention and difficulty of exactly controlling the middle polarization states. In order to overcome the issues, we develop a ferroelectric tunnel junction with smooth ultrathin polycrystalline BiFeO3 (BFO) film. Through controlling the polarization state and oxygen vacancy migration using voltage pulses, we demonstrate that voltage-controlled barrier yields a memristive behavior in the device, in which the resistance variations exceed over two orders of magnitude. And we achieve multi logic states written and read easily using voltage pulses in the device. Especially the device is integrated with the silicon technology in modern microelectronics. Our results suggest new opportunity for ferroelectrics as high storage density nonvolatile memories.

11.
J Phys Chem Lett ; 8(8): 1804-1809, 2017 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-28387118

RESUMO

Lead halide perovskite solar cells have recently emerged as a very promising photovoltaic technology due to their excellent power conversion efficiencies; however, the toxicity of lead and the poor stability of perovskite materials remain two main challenges that need to be addressed. Here, for the first time, we report a lead-free, highly stable C6H4NH2CuBr2I compound. The C6H4NH2CuBr2I films exhibit extraordinary hydrophobic behavior with a contact angle of ∼90°, and their X-ray diffraction patterns remain unchanged even after 4 h of water immersion. UV/vis absorption spectrum shows that C6H4NH2CuBr2I compound has an excellent optical absorption over the entire visible spectrum. We applied this copper-based light absorber in printable mesoscopic solar cell for the initial trial and achieved a power conversion efficiency of ∼0.5%. Our study represents an alternative pathway to develop low-toxic and highly stable organic-inorganic hybrid materials for photovoltaic application.

12.
Biotechnol Appl Biochem ; 64(2): 218-224, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27696508

RESUMO

In this study, trends in synonymous codons usage of Volvariella volvecea have been first examined by analysis of complete coding sequences and gene chip data. The results showed that GC content at three codon positions are obviously different and there were several factors shaping the codon usage of V. volvacea genes, including base composition. The comparison of codon usage among four edible fungi such as V. volvacea, Agaricus bisporus, Coprinopsis cinerea, and Pleurotus ostreatus indicated that the similar codon usage pattern was used among V. volvacea, A. bisporus and P. ostreatus, but there was significantly different codon usage pattern of C. cinerea. Two arrays of optimal codons were determined by effective number of codons (ENC) values and gene chip database separately, resulting that most of the ENC-predicted optimal codons were included in the array of gene chip resulted optimal codons. This study can provide useful information for codon usage pattern analysis and gene transformation of V. volvacea.


Assuntos
Códon/genética , Volvariella/genética , Composição de Bases/genética , Plantas Comestíveis/genética
13.
PLoS One ; 11(10): e0163352, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27706188

RESUMO

In this study, assessment of the safety of transgenic rice T1C-1 expressing Cry1C was carried out by: (1) studying horizontal gene transfer (HGT) in Sprague Dawley rats fed transgenic rice for 90 d; (2) examining the effect of Cry1C protein in vitro on digestibility and allergenicity; and (3) studying the changes of intestinal microbiota in rats fed with transgenic rice T1C-1 in acute and subchronic toxicity tests. Sprague Dawley rats were fed a diet containing either 60% GM Bacillus thuringiensis (Bt) rice T1C-1 expressing Cry1C protein, the parental rice Minghui 63, or a basic diet for 90 d. The GM Bt rice T1C-1 showed no evidence of HGT between rats and transgenic rice. Sequence searching of the Cry1C protein showed no homology with known allergens or toxins. Cry1C protein was rapidly degraded in vitro with simulated gastric and intestinal fluids. The expressed Cry1C protein did not induce high levels of specific IgG and IgE antibodies in rats. The intestinal microbiota of rats fed T1C-1 was also analyzed in acute and subchronic toxicity tests by DGGE. Cluster analysis of DGGE profiles revealed significant individual differences in the rats' intestinal microbiota.


Assuntos
Alérgenos/imunologia , Proteínas de Bactérias/genética , Transferência Genética Horizontal/fisiologia , Intestinos/microbiologia , Oryza/genética , Receptores de Superfície Celular/genética , Animais , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Análise por Conglomerados , Fezes/microbiologia , Feminino , Alimentos Geneticamente Modificados/toxicidade , Variação Genética , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Proteínas de Insetos , Mucosa Intestinal/metabolismo , Masculino , Microbiota , Músculos/metabolismo , Oryza/metabolismo , Filogenia , Plantas Geneticamente Modificadas/genética , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Superfície Celular/imunologia , Receptores de Superfície Celular/metabolismo , Testes de Toxicidade Aguda
14.
Biotechnol Appl Biochem ; 63(5): 605-615, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26234394

RESUMO

Volvariella volvacea is difficult to store fresh because of the lack of low-temperature resistance. Many traditional mutagenic strategies have been applied in order to select out strains resistant to low temperature, but few commercially efficient strains have been produced. In order to break through the bottleneck of traditional breeding and significantly improve low-temperature resistance of the edible fungus V. volvacea, strains resistant to low temperature were constructed by genome shuffling. The optimum conditions of V. volvacea strain mutation, protoplast regeneration, and fusion were determined. After protoplasts were treated with 1% (v/v) ethylmethylsulfonate (EMS), 40 Sec of ultraviolet (UV) irradiation, 600 Gy electron beam implantation, and 750 Gy60 Co-γ irradiation, separately, the lethality was within 70%-80%, which favored generating protoplasts being used in following forward mutation. Under these conditions, 16 strains of V. volvacea mutated by EMS, electron beam, UV irradiation, and 60 Co-γ irradiation were obtained. The 16 mutated protoplasts were selected to serve as the shuffling pool based on their excellent low-temperature resistance. After four rounds of genome shuffling and low-temperature resistance testing, three strains (VF1 , VF2 , and VF3 ) with high genetic stability were screened. VF1 , VF2 , and VF3 significantly enhanced fruit body shelf life to 20, 28, and 28 H at 10 °C, respectively, which exceeded 25%, 75%, and 75%, respectively, compared with the storage time of V23, the most low-temperature-resistant strain. Genome shuffling greatly improved the low-temperature resistance of V. volvacea, and shortened the course of screening required to generate desirable strains. To our knowledge, this is the first paper to apply genome shuffling to breeding new varieties of mushroom, and offers a new approach for breeding edible fungi with optimized phenotype.


Assuntos
Embaralhamento de DNA/métodos , Genômica , Temperatura Ambiente , Volvariella/genética , Volvariella/fisiologia , Temperatura Alta/efeitos adversos , Mutagênese , Mutação , Protoplastos/metabolismo , Protoplastos/fisiologia , Técnica de Amplificação ao Acaso de DNA Polimórfico , Raios Ultravioleta/efeitos adversos , Volvariella/efeitos da radiação
15.
Peptides ; 53: 70-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24361453

RESUMO

A novel platelet aggregation inhibitory peptide, named BB octapeptide, was isolated from stiff silkworm (Bombyx batryticatus) by gel filtration, anion-exchange, and reverse-phase high performance liquid chromatography. The molecular mass of the peptide was determined to be 885 Da using electrospray ionization mass spectrometry, and the sequence was identified as Asp-Pro-Asp-Ala-Asp-IIe-Leu-Gln using the Edman degradation method. To test its biological activity, the peptide was chemically synthesized using Fmoc solid-phase synthesis method. BB octapeptide inhibited rabbit platelet aggregation that was induced by collagen and epinephrine, with the IC50 values of 91.14 µM and 104.50 µM, respectively. After intravenous administrated in mice (30 mg/kg, 4 days), BB octapeptide showed similar ex vivo efficacy of inhibiting platelet aggregation as aspirin (10 mg/kg). In addition, this peptide prevented paralysis and death in pulmonary thromboembolism model and significantly reduced ferric chloride-induced thrombus formation in rats. Moreover, it exhibited low cytotoxicity in a cellular model. In conclusion, this is the first report that a novel platelet aggregation inhibitory peptide was isolated from stiff silkworm (B. batryticatus). Due to the excellent efficacy in reducing platelet aggregation and low toxicity, it can be a valuable lead compound for new drug design and development.


Assuntos
Bombyx/química , Inibidores da Agregação de Plaquetas/química , Inibidores da Agregação de Plaquetas/farmacologia , Sequência de Aminoácidos , Animais , Camundongos , Dados de Sequência Molecular , Agregação Plaquetária/efeitos dos fármacos , Coelhos , Ratos
16.
Sheng Wu Gong Cheng Xue Bao ; 30(9): 1424-35, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25720157

RESUMO

We analyzed the whole genome coding sequence of Volvariella volvacea to study the pattern utilization of codons by Codon W 1.4.2. As results, 24 optimal codons were identified. Moreover, the frequency of codons usage was calculated by CUSP program. We compared the frequency of codons usage of V. volvacea with other organisms including 6 modal value species (Homo sapiens, Saccharomys cerevisiae, Arabidopsis thalian, Mus musculus, Danio rerio and Drosophila melanogaster) and 4 edible fungi (Coprinopsis cinerea, Agaricus bisporus, Lentinula edodes and Pleurotus ostreatus). We found that there were less differences in 3 edible fungi (excluding Pleurotus ostreatus) than 6 modal value species, comparing with the frequency of codons usage of V. volvacea. With software SPSS16.0, cluster analysis which showed differences in the size of codon bias, reflects the evolutionary relationships between species, which can be used as a reference of evolutionary relationships of species. This was the first time for analysis the codon preference among the whole coding sequences of edible fungi, serving as theoretical basis to apply genetic engineering of V. volvacea.


Assuntos
Códon , DNA Fúngico/genética , Volvariella/genética , Agaricales/genética , Animais , Arabidopsis/genética , Análise por Conglomerados , Drosophila melanogaster/genética , Humanos , Camundongos , Saccharomyces cerevisiae/genética , Software , Peixe-Zebra/genética
17.
Int J Pept Res Ther ; 19: 303-311, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24273471

RESUMO

Centipedes have been used as traditional medicine for thousands of years in China. Centipede venoms consist of many biochemical peptides and proteins. Factor Xa (FXa) is a serine endopeptidase that plays the key role in blood coagulation, and has been used as a new target for anti-thrombotic drug development. A novel FXa inhibitor, a natural peptide with the sequence of Thr-Asn-Gly-Tyr-Thr (TNGYT), was isolated from the venom of Scolopendra subspinipesmutilans using a combination of size-exclusion and reverse-phase chromatography. The molecular weight of the TNGYT peptide was 554.3 Da measured by electrospray ionization mass spectrometry. The amino acid sequence of TNGYT was determined by Edman degradation. TNGYT inhibited the activity of FXa in a dose-dependent manner with an IC50 value of 41.14 mg/ml. It prolonged the partial thromboplastin time and prothrombin time in both in vitro and ex vivo assays. It also significantly prolonged whole blood clotting time and bleeding time in mice. This is the first report that an FXa inhibiting peptide was isolated from centipedes venom.

18.
PLoS One ; 7(12): e52507, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23300690

RESUMO

In a 90-day study, Sprague Dawley rats were fed transgenic T1C-1 rice expressing Cry1C protein and were compared with rats fed non-transgenic parental rice Minghui 63 and rats fed a basal diet. No adverse effects on animal behavior or weight gain were observed during the study. Blood samples were collected and analyzed, and standard hematological and biochemical parameters were compared. A few of these parameters were found to be significantly different, but were within the normal reference intervals for rats of this breed and age, and were thus not considered to be treatment-related. Following sacrifice, a large number of organs were weighed, and macroscopic and histopathological examinations were performed with no changes reported. The aim of this study was to use a known animal model to determine the safety of the genetically modified (GM) rice T1C-1. The results showed no adverse or toxic effects due to T1C-1 rice when tested in this 90-day study.


Assuntos
Proteínas de Bactérias/genética , Dieta/efeitos adversos , Inocuidade dos Alimentos , Alimentos Geneticamente Modificados/toxicidade , Oryza/genética , Testes de Toxicidade , Animais , Bacillus thuringiensis/genética , Análise Química do Sangue , Peso Corporal , Ingestão de Alimentos , Fezes/microbiologia , Feminino , Expressão Gênica , Testes Hematológicos , Masculino , Tamanho do Órgão , Plantas Geneticamente Modificadas , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
19.
J AOAC Int ; 94(4): 1227-32, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21919356

RESUMO

The validation of the anthocyanin synthase (ANS) gene as a carnation endogenous reference gene applicable both in classical and real-time PCR methods is a prerequisite for the development of PCR assays for genetically modified (GM) carnation detection. This is important due to the fact that GM carnation lines, developed by Florigene Pty Ltd, have been approved for commercialization. In this study, both methods were tested on 14 different carnation cultivars, and identical amplification products were obtained with all of them. No amplification products were observed with samples from 14 other plant species, which demonstrated that the system was specific to carnation. The results of Southern blot analysis confirmed that the ANS gene had a low copy number in the 10 tested carnation varieties. In qualitative and real-time PCR assays, the LOD values of 0.05 and 0.005 ng carnation DNA, respectively, were validated. Moreover, the real-time PCR system was validated with high PCR efficiency and linearity. Thus, the ANS gene had species specificity, low heterogeneity, and low copy number among the tested cultivars. These results provide evidence that the gene can be used as an endogenous reference gene of carnation, as well as in qualitative and quantitative PCR systems.


Assuntos
Dianthus/genética , Genes de Plantas/genética , Reação em Cadeia da Polimerase/métodos , Antocianinas/genética , Antocianinas/metabolismo , DNA de Plantas/análise , Regulação da Expressão Gênica de Plantas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Especificidade da Espécie
20.
Chem Commun (Camb) ; 47(37): 10380-2, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21845269

RESUMO

Uniform yolk-shell V(2)O(5) microspheres were synthesized via a facile template-free solvothermal route and subsequent calcination treatment in air. The resulting cathode materials showed a high specific capacity of 220 mA h g(-1) after 30 cycles and good rate capability.


Assuntos
Técnicas de Química Sintética/métodos , Fontes de Energia Elétrica , Lítio/química , Microesferas , Compostos de Vanádio/química , Compostos de Vanádio/síntese química , Cristalização , Eletroquímica , Eletrodos , Microtecnologia
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