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1.
Molecules ; 26(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065427

RESUMO

Early plants began colonizing earth about 450 million years ago. During the process of coevolution, their metabolic cellular pathways produced a myriad of natural chemicals, many of which remain uncharacterized biologically. Popular preparations containing some of these molecules have been used medicinally for thousands of years. In Brazilian folk medicine, plant extracts from the bamboo plant Guadua paniculata Munro have been used for the treatment of infections and pain. However, the chemical basis of these therapeutic effects has not yet been identified. Here, we performed protein biochemistry and downstream pharmacological assays to determine the mechanisms underlying the anti-inflammatory and antinociceptive effects of an aqueous extract of the G. paniculata rhizome, which we termed AqGP. The anti-inflammatory and antinociceptive effects of AqGP were assessed in mice. We identified and purified a protein (AgGP), with an amino acid sequence similar to that of thaumatins (~20 kDa), capable of repressing inflammation through downregulation of neutrophil recruitment and of decreasing hyperalgesia in mice. In conclusion, we have identified the molecule and the molecular mechanism responsible for the anti-inflammatory and antinociceptive properties of a plant commonly used in Brazilian folk medicine.


Assuntos
Analgésicos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Bambusa/química , Extratos Vegetais/uso terapêutico , Sequência de Aminoácidos , Analgésicos/administração & dosagem , Animais , Anti-Inflamatórios/administração & dosagem , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Hiperalgesia/tratamento farmacológico , Inflamação/tratamento farmacológico , Células MCF-7 , Masculino , Camundongos , Células NIH 3T3 , Extratos Vegetais/administração & dosagem , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
2.
Mol Plant Microbe Interact ; 31(10): 1048-1059, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29663868

RESUMO

Nematodes are devastating pests that infect most cultivated plant species and cause considerable agricultural losses worldwide. The understanding of metabolic adjustments induced during plant-nematode interaction is crucial to generate resistant plants or to select more efficient molecules to fight against this pest. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) has been used herein for in situ detection and mapping endogenous polypeptides and secondary metabolites from nematode-induced gall tissue. One of the major critical features of this technique is sample preparation; mainly, the generation of intact sections of plant cells with their rigid cell walls and vacuolated cytoplasm. Our experimental settings allowed us to obtain sections without contamination of exogenous ions or diffusion of molecules and to map the differential presence of low and high molecular weight ions in uninfected roots compared with nematode-induced galls. We predict the presence of lipids in both uninfected roots and galls, which was validated by MALDI time-of-flight tandem mass spectrometry and high-resolution mass spectrometry analysis of lipid extracts. Based on the isotopic ion distribution profile, both esters and glycerophospholipids were predicted compounds and may be playing an important role in gall development. Our results indicate that the MALDI-MSI technology is a promising tool to identify secondary metabolites as well as peptides and proteins in complex plant tissues like galls to decipher molecular processes responsible for infection and maintenance of these feeding sites during nematode parasitism.


Assuntos
Nematoides/fisiologia , Peptídeos/química , Raízes de Plantas/metabolismo , Solanum lycopersicum/parasitologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Animais , Lipídeos/química , Peptídeos/metabolismo , Raízes de Plantas/parasitologia
3.
Insects ; 12(12)2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34940218

RESUMO

The coffee leaf miner (CLM) Leucoptera coffeella moth is a major threat to coffee production. Insect damage is related to the feeding behavior of the larvae on the leaf. During the immature life stages, the insect feeds in the mesophyll triggering necrosis and causing loss of photosynthetic capacity, defoliation and significant yield loss to coffee crops. Chemical control is used to support the coffee production chain, though market requirements move toward conscious consumption claiming for more sustainable methods. In this overview, we discuss aspects about the CLM concerning biology, history, geographical distribution, economic impacts, and the most relevant control strategies in progress. Insights to develop an integrated approach for a safer and eco-friendly control of the CLM are discussed here, including bio-extracts, nanotechnology, pheromones, and tolerant cultivars.

4.
Int J Biol Macromol ; 181: 1124-1170, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33864867

RESUMO

Chitosan is one of the most abundant natural polymer worldwide, and due to its inherent characteristics, its use in industrial processes has been extensively explored. Because it is biodegradable, biocompatible, non-toxic, hydrophilic, cheap, and has good physical-chemical stability, it is seen as an excellent alternative for the replacement of synthetic materials in the search for more sustainable production methodologies. Thus being, a possible biotechnological application of Chitosan is as a direct support for enzyme immobilization. However, its applicability is quite specific, and to overcome this issue, alternative pretreatments are required, such as chemical and physical modifications to its structure, enabling its use in a wider array of applications. This review aims to present the topic in detail, by exploring and discussing methods of employment of Chitosan in enzymatic immobilization processes with various enzymes, presenting its advantages and disadvantages, as well as listing possible chemical modifications and combinations with other compounds for formulating an ideal support for this purpose. First, we will present Chitosan emphasizing its characteristics that allow its use as enzyme support. Furthermore, we will discuss possible physicochemical modifications that can be made to Chitosan, mentioning the improvements obtained in each process. These discussions will enable a comprehensive comparison between, and an informed choice of, the best technologies concerning enzyme immobilization and the application conditions of the biocatalyst.


Assuntos
Biocatálise , Quitosana/química , Enzimas Imobilizadas/química , Enzimas/química , Biotecnologia/tendências , Concentração de Íons de Hidrogênio , Lipase/química , Polímeros/química
5.
Cancer Immunol Immunother ; 59(1): 173-81, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19629479

RESUMO

Laryngeal cancer is a significant disease worldwide, which presents an increasing incidence. Two contrasting ideas of the immune system role during cancer development are accepted: (1) it fights tumor cells, and (2) it aids tumor progression. Thus, there is no clear understanding about the immune response in laryngeal cancer. Furthermore, since tobacco is the main cause of laryngeal cancer and it contains various carcinogenic components, including metallic elements, these may play a role on cancer development. Plasmas of patients with laryngeal cancer and of healthy smokers were evaluated by 2D gel electrophoresis and mass spectrometry. Proteins were detected on every gel around pH 4.0-10.0 from molecular mass of 10-60 kDa. Few differences were found among cancer and control patients. However, three spots gathered between pI 7.3 and 7.6 with different molecular masses appeared exclusively in cancer profiles. From ten spots identified, six correspond to immune system components, including the three differential ones. The latter were observed only in cancer patients. The presence of several trace elements in the identified proteins was determined by inductively coupled plasma mass spectrometry, where chromium was increased in all proteins analyzed from patients with cancer. This study reinforces the importance of the immune response as target in the understanding and treatment of laryngeal cancer and the possibility that chromium is important in the carcinogenic progress.


Assuntos
Biomarcadores Tumorais/sangue , Proteínas Sanguíneas/metabolismo , Carcinoma de Células Escamosas/sangue , Neoplasias Laríngeas/sangue , Proteoma/metabolismo , Oligoelementos/sangue , Eletroforese em Gel Bidimensional , Humanos , Espectrometria de Massas por Ionização por Electrospray
6.
BMC Biotechnol ; 10: 44, 2010 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-20565807

RESUMO

BACKGROUND: Coffee is an important crop and is crucial to the economy of many developing countries, generating around US$70 billion per year. There are 115 species in the Coffea genus, but only two, C. arabica and C. canephora, are commercially cultivated. Coffee plants are attacked by many pathogens and insect-pests, which affect not only the production of coffee but also its grain quality, reducing the commercial value of the product. The main insect-pest, the coffee berry borer (Hypotheneumus hampei), is responsible for worldwide annual losses of around US$500 million. The coffee berry borer exclusively damages the coffee berries, and it is mainly controlled by organochlorine insecticides that are both toxic and carcinogenic. Unfortunately, natural resistance in the genus Coffea to H. hampei has not been documented. To overcome these problems, biotechnological strategies can be used to introduce an alpha-amylase inhibitor gene (alpha-AI1), which confers resistance against the coffee berry borer insect-pest, into C. arabica plants. RESULTS: We transformed C. arabica with the alpha-amylase inhibitor-1 gene (alpha-AI1) from the common bean, Phaseolus vulgaris, under control of the seed-specific phytohemagglutinin promoter (PHA-L). The presence of the alpha-AI1 gene in six regenerated transgenic T1 coffee plants was identified by PCR and Southern blotting. Immunoblotting and ELISA experiments using antibodies against alpha-AI1 inhibitor showed a maximum alpha-AI1 concentration of 0.29% in crude seed extracts. Inhibitory in vitro assays of the alpha-AI1 protein against H. hampei alpha-amylases in transgenic seed extracts showed up to 88% inhibition of enzyme activity. CONCLUSIONS: This is the first report showing the production of transgenic coffee plants with the biotechnological potential to control the coffee berry borer, the most important insect-pest of crop coffee.


Assuntos
Coffea/metabolismo , Controle de Insetos/métodos , Phaseolus/genética , Lectinas de Plantas/genética , alfa-Amilases/antagonistas & inibidores , Animais , Coffea/genética , Besouros , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plasmídeos , Regiões Promotoras Genéticas , Sementes/genética , Sementes/metabolismo , Transformação Genética
7.
Artigo em Inglês | MEDLINE | ID: mdl-20862341

RESUMO

The Cry1Ia12 entomotoxin from a Brazilian Bacillus thuringiensis strain is currently being expressed in cotton cultivars to confer resistance to insect-pests. The present study aimed to assess the effects of a diet containing Cry1Ia12 protein on growing rats. A test diet containing egg white and Cry1Ia12 (0.1% of total protein) as a protein source was offered to rats for ten days. In addition, an acute toxicity bioassay was performed in rats with a single oral dose of the entomotoxin (12 mg/animal). No adverse effects were observed in the animals receiving the test diet when compared to those receiving a control diet (egg white). The analysed parameters included relative dry weight of internal organs, duodenum histology, blood biochemistry, and nutritional parameters. The results of the acute toxicity test showed no mortality or behaviour alteration. Thus, Cry1Ia12 toxin at the tested concentration does not cause deleterious effects on growing rats when incorporated in the diet for 10 days.


Assuntos
Bacillus thuringiensis/genética , Toxinas Bacterianas/toxicidade , Proteínas Recombinantes/toxicidade , Administração Oral , Animais , Toxinas Bacterianas/administração & dosagem , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Dieta , Escherichia coli , Vetores Genéticos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Plantas Geneticamente Modificadas , Ratos , Ratos Endogâmicos WF , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
8.
J Invertebr Pathol ; 104(3): 227-30, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20144614

RESUMO

Biotech crops expressing Bacillus thuringiensis Cry toxins present a valuable approach for insect control. Cry8Ka5, which is highly toxic to the cotton boll weevil (Anthonomus grandis), was used as a model to study toxin-ligand interactions. Three Cry-binding proteins were detected after toxin overlay assays. Following de novo sequencing, a heat-shock cognate protein and a V-ATPase were identified, whilst a approximately 120 kDa protein remained unknown. Additional Cry8Ka5-binding proteins were visualized by two-dimensional gel electrophoresis ligand blots.


Assuntos
Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/metabolismo , Sistema Digestório/metabolismo , Endotoxinas/metabolismo , Proteínas Hemolisinas/metabolismo , Inseticidas/metabolismo , Controle Biológico de Vetores/métodos , Gorgulhos/metabolismo , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/química , Endotoxinas/química , Proteínas de Choque Térmico HSC70/análise , Proteínas de Choque Térmico HSC70/metabolismo , Proteínas Hemolisinas/química , Inseticidas/química , Larva/metabolismo , Ligação Proteica , ATPases Vacuolares Próton-Translocadoras/análise , ATPases Vacuolares Próton-Translocadoras/metabolismo
9.
Prep Biochem Biotechnol ; 40(2): 152-63, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20213576

RESUMO

The identification of plant proteins expressed in response to phytopathogens is a remaining challenge to proteome methodology. Proteomic methods, such as electrophoresis and mass spectrometry have been extensively used for protein differential expression studies in several plants including Arabidopsis thaliana, rice, and wheat. However, in coffee (Coffea canephora) and cotton (Gossypium hirsutum), bidimensional electrophoresis (2-DE) analysis has been rarely employed. Moreover, global protein expression in both agricultural plants in response to biotic stress conditions had not been reported until now. In this study, Meloidogyne paranaensis and M. incognita, two devastating phytonematodes for numerous crop cultures, were used to infect resistant genotypes of coffee and cotton plants. The protein expression of infected- and non-infected roots were evaluated by 2-DE following in silico experiments. Additionally, gels were stained with silver nitrate and/or Coomassie brilliant blue in order to obtain an optimized method for proteomic analysis of plant-nematode interaction. The 2-DE analysis revealed an enhanced number of protein spots, as well as differentially expressed proteins, when Coomassie brilliant blue was used. The results obtained here could be extended to other plant species, providing valuable information to root-nematode interactions.


Assuntos
Coffea/metabolismo , Eletroforese em Gel Bidimensional/métodos , Gossypium/metabolismo , Gossypium/parasitologia , Proteínas de Plantas/análise , Tylenchoidea/fisiologia , Animais , Coffea/parasitologia , Perfilação da Expressão Gênica/métodos , Raízes de Plantas/metabolismo , Raízes de Plantas/parasitologia , Proteoma/análise , Proteômica/métodos
10.
3 Biotech ; 10(6): 254, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32426206

RESUMO

In this work, the concept of lipase cocktail has been proposed in the ultrasound-assisted hydrolysis of coconut oil. Lipase from Thermomyces lanuginosus (TLL), lipase from Rhizomucor miehei (RML), and lipase B from Candida antarctica (CALB) were evaluated as biocatalysts in different combinations. The best conversion (33.66%) was achieved using only RML; however, the best lipase cocktail (75% RML and 25% CALB) proposed by the triangular response surface was used to achieve higher conversions. At the best lipase cocktail, reaction parameters [temperature, biocatalyst content and molar ratio (water/oil)] were optimized by a Central Composite Design, allowing to obtain more than 98% of conversion in the hydrolysis of coconut oil in 3 h of incubation at 37 kHz, 300 W and 45 °C by using 20% of the lipase cocktail (w/w) and a molar ratio of 7.5:1 (water/oil). The lipase cocktail retained about 50% of its initial activity after three consecutive cycles of hydrolysis. To the authors' knowledge, up to date, this communication is the first report in the literature for the ultrasound-assisted hydrolysis of coconut oil catalyzed by a cocktail of lipases. Under ultrasound irradiation, the concept of lipase cocktail was successfully applied, and this strategy could be useful for the other types of reactions using heterogeneous substrates.

11.
Exp Parasitol ; 121(2): 115-23, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18952081

RESUMO

Herein we describe the cloning and characterization of a cDNA encoding an aspartic proteinase from the root-knot nematode Meloidogyne incognita. Using PCR techniques, a 1471-bp cDNA fragment encoding a cathepsin D-like (Mi-asp1) transcript was isolated from second-stage larvae mRNA. Its predicted amino acid sequence comprises a pro-region of 71 amino acid residues and a mature protease of 378 amino acid residues with a predicted molecular mass of 41.502kDa. Protein sequence comparisons of Mi-asp1 with GenBank (DQ360827) sequences showed 59-71% identity with nematode-specific cathepsin D-like aspartic proteinases. Southern blot analysis, RT-PCR amplification and EST mining suggest the existence of a developmentally expressed gene family encoding aspartic proteinases in M. incognita. Mi-asp1 may represent a potential target for molecular intervention for the purposes of plant-parasitic nematode control.


Assuntos
Ácido Aspártico Endopeptidases/genética , DNA Complementar/química , DNA de Helmintos/química , Tylenchoidea/enzimologia , Tylenchoidea/genética , Sequência de Aminoácidos , Animais , Ácido Aspártico Endopeptidases/química , Ácido Aspártico Endopeptidases/metabolismo , Sequência de Bases , Southern Blotting , Clonagem Molecular , Análise por Conglomerados , Etiquetas de Sequências Expressas , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Larva/enzimologia , Larva/genética , Solanum lycopersicum/parasitologia , Dados de Sequência Molecular , Óvulo/enzimologia , Raízes de Plantas/parasitologia , RNA de Helmintos/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Especificidade por Substrato
12.
Curr Protein Pept Sci ; 9(2): 108-16, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18393883

RESUMO

In recent years, a strong emphasis has been given in deciphering the function of genes unraveled by the completion of several genome sequencing projects. In plants, functional genomics has been massively used in order to search for gene products of agronomic relevance. As far as root-pathogen interactions are concerned, several genes are recognized to provide tolerance/resistance against potential invaders. However, very few proteins have been identified by using current proteomic approaches. One of the major drawbacks for the successful analysis of root proteomes is the inherent characteristics of this tissue, which include low volume content and high concentration of interfering substances such as pigments and phenolic compounds. The proteome analysis of plant-pathogen interactions provides important information about the global proteins expressed in roots in response to biotic stresses. Moreover, several pathogenic proteins superimpose the plant proteome and can be identified and used as targets for the control of viruses, bacteria, fungi and nematode pathogens. The present review focuses on advances in different proteomic strategies dedicated to the challenging analysis of plant defense proteins expressed during bacteria-, fungi- and nematode-root interactions. Recent developments, limitations of the current techniques, and technological perspectives for root proteomics aiming at the identification of resistance-related proteins are discussed.


Assuntos
Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Proteoma , Proteômica/métodos , Animais , Bactérias/metabolismo , Eletroforese em Gel Bidimensional , Fungos/metabolismo , Espectrometria de Massas , Nematoides/metabolismo , Proteínas de Plantas/isolamento & purificação , Raízes de Plantas/microbiologia , Raízes de Plantas/parasitologia , Plantas/metabolismo , Plantas/microbiologia , Plantas/parasitologia
13.
FEBS J ; 275(15): 3731-46, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18616468

RESUMO

Over the years, several studies have been performed to analyse plant-pathogen interactions. Recently, functional genomic strategies, including proteomics and transcriptomics, have contributed to the effort of defining gene and protein function and expression profiles. Using these 'omic' approaches, pathogenicity- and defence-related genes and proteins expressed during phytopathogen infections have been identified and enormous datasets have been accumulated. However, the understanding of molecular plant-pathogen interactions is still an intriguing area of investigation. Proteomics has dramatically evolved in the pursuit of large-scale functional assignment of candidate proteins and, by using this approach, several proteins expressed during phytopathogenic interactions have been identified. In this review, we highlight the proteins expressed during plant-virus, plant-bacterium, plant-fungus and plant-nematode interactions reported in proteomic studies, and discuss these findings considering the advantages and limitations of current proteomic tools.


Assuntos
Proteínas de Plantas/fisiologia , Plantas/microbiologia , Proteômica , Animais , Nematoides/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas/parasitologia , Plantas/virologia
14.
BMC Res Notes ; 6: 196, 2013 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-23668315

RESUMO

BACKGROUND: Soybean pathogens and pests reduce grain production worldwide. Biotic interaction cause extensive changes in plant gene expression profile and the data produced by functional genomics studies need validation, usually done by quantitative PCR. Nevertheless, this technique relies on accurate normalization which, in turn, depends upon the proper selection of stable reference genes for each experimental condition. To date, only a few studies were performed to validate reference genes in soybean subjected to biotic stress. Here, we report reference genes validation in soybean during root-knot nematode (Meloidogyne incognita) parasitism and velvetbean caterpillar (Anticarsia gemmatalis) attack. FINDINGS: The expression stability of nine classical reference genes (GmCYP2, GmELF1A, GmELF1B, GmACT11, GmTUB, GmTUA5, GmG6PD, GmUBC2 and GmUBC4) was evaluated using twenty-four experimental samples including different organs, developmental stages, roots infected with M. incognita and leaves attacked by A. gemmatalis. Two different algorithms (geNorm and NormFinder) were used to determine expression stability. GmCYP2 and GmUBC4 are the most stable in different organs. Considering the developmental stages, GmELF1A and GmELF1B genes are the most stable. For spatial and temporal gene expression studies, normalization may be performed using GmUBC4, GmUBC2, GmCYP2 and GmACT11 as reference genes. Our data indicate that both GmELF1A and GmTUA5 are the most stable reference genes for data normalization obtained from soybean roots infected with M. incognita, and GmCYP2 and GmELF1A are the most stable in soybean leaves infested with A. gemmatalis. CONCLUSIONS: Future expression studies using nematode infection and caterpilar infestation in soybean plant may utilize the reference gene sets reported here.


Assuntos
Genes de Plantas , Glycine max/genética , Insetos/fisiologia , Nematoides/fisiologia , Reação em Cadeia da Polimerase/métodos , Animais , Sequência de Bases , Primers do DNA , Glycine max/parasitologia
15.
Plant Sci ; 180(2): 276-82, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21421371

RESUMO

Meloidogyne spp., plant-parasitic nematodes present worldwide, are intensively studied because of the damage caused to a large variety of agronomically important crops. Several reports indicate that proteins from the Meloidogyne spp. dorsal gland might play an important role to allow proper establishment of a functional nematode feeding site. The precise role of these proteins in the process of feeding cell development is unknown. To gain insights into the function of these secreted M. incognita proteins, we constitutively (ectopically) expressed the nematodes dorsal gland protein 7E12 in tobacco plants. It was found that the number of galls at 8 and 16 days after nematode infection was significantly higher in transgenic plants compared to control plants. Eggs from nematodes in transgenic plants hatched faster than those in control plants. Histological analysis of nematode induced galls in transgenic plants clearly shows a different morphology. Giant feeding cells harbor more vacuoles and an increased amount of cell wall invaginations, while neighboring cells surrounding feeding cells are more numerous. These results suggest that the presence of the 7E12 protein in tobacco accelerates gall formation. This assumption is supported by our data illustrating faster gall formation and egg eclosion in transgenic plants.


Assuntos
Proteínas de Helminto/genética , Nicotiana/genética , Nicotiana/parasitologia , Doenças das Plantas/parasitologia , Tylenchoidea/fisiologia , Animais , DNA Complementar/genética , Feminino , Expressão Gênica , Proteínas de Fluorescência Verde , Proteínas de Helminto/metabolismo , Interações Hospedeiro-Parasita , Contagem de Ovos de Parasitas , Fenótipo , Doenças das Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/parasitologia , Raízes de Plantas/ultraestrutura , Plantas Geneticamente Modificadas/parasitologia , RNA Mensageiro/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Tempo , Nicotiana/ultraestrutura , Tylenchoidea/genética , Tylenchoidea/crescimento & desenvolvimento , Tylenchoidea/patogenicidade
16.
Protein Expr Purif ; 58(1): 61-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18171621

RESUMO

beta-N-Acetylhexosaminidases (EC 3.2.1.52) belong to an enzyme family that hydrolyzes terminal beta-d-N-glucosamine and beta-d-N-galactosamine residues from oligosaccharides. In this report, we purified a novel beta-N-acetylhexosaminidase (Pcb-NAHA1) from the marine zoanthid Palythoa caribaeorum by applying ammonium sulfate fractionation, affinity chromatography on a chitin column, followed by two rounds of size exclusion chromatography. SDS-PAGE analysis indicated a single band protein of apparent homogeneity with a molecular mass of 25kDa. The purified enzyme preferentially hydrolyzed p-nitrophenyl-2-acetoamide-2-deoxyamide-2-deoxy-beta-d-N-acetylglucosamide (pNP-GlcNAc) and to a lesser extent p-nitrophenyl-2-acetoamide-2-deoxyamide-2-deoxy-beta-d-N-acetylgalactosamide (pNP-GalNAc). Detailed kinetic analysis using pNP-GlcNAc resulted in a specific activity of 57.9 U/mg, a K(m) value of 0.53 mM and a V(max) value of 88.1 micromol/h/mg and k(cat) value of 0.61s(-1). Furthermore, purified Pcb-NAHA1 enzyme activity was decreased by Hg Cl(2) or maltose and stimulated in the presence of Na(2)SeO(4,) BaCl(2), MgCl(2,) chondroitin 6-sulfate, and phenylmethylsulfonylfluoride. The optimum activity of Pcb-NAHA1 was observed at pH 5.0 and elevated temperatures (45-60 degrees C). Direct sequencing of proteolytic fragments generated from Pcb-NAHA1 revealed remarkable similarities to plant chitinases, which belong to family 18, although no chitinase activity was detected with Pcb-NAHA1. We conclude that beta-N-acetylhexosaminidases, representing a type of exochitinolytic activity, and endo-chitinases share common functional domains and/or may have evolved from a common ancestor.


Assuntos
Antozoários/enzimologia , beta-N-Acetil-Hexosaminidases/isolamento & purificação , beta-N-Acetil-Hexosaminidases/metabolismo , Sequência de Aminoácidos , Animais , Antozoários/metabolismo , Cinética , Dados de Sequência Molecular , Alinhamento de Sequência , Especificidade por Substrato , beta-N-Acetil-Hexosaminidases/química
17.
Arch Insect Biochem Physiol ; 66(4): 169-82, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18000877

RESUMO

The Mexican bean weevil, Zabrotes subfasciatus, feeds on several seeds such as Vigna unguiculata, Phaseolus vulgaris, and Pisum sativum, causing severe crop losses. This ability to obtain essential compounds from different diets could possibly be explained due to a wide variability of digestive proteinases present in the weevil's midgut. These may improve digestion of many different dietary proteins. Coleopteran serine-like proteinases have not been thoroughly characterized at the molecular level. In this report, a full-length cDNA encoding a trypsin-like protein, named ZsTRYP, was isolated from Z. subfasciatus larvae using RT-PCR, 5' and 3' RACE techniques. The quantitative real-time PCR analysis strongly correlated the Zstryp transcript accumulation to the major feeding developmental larval stage. Zstryp cDNA was subcloned into pET101 vector and expressed in a Escherichia coli BL21(DE3) strain. Nickel-nitrilotriacetic acid (Ni-NTA) affinity chromatography was used to purify a 29.0-kDa recombinant enzyme. The purified ZsTRYP was then assayed with several synthetic peptide substrates and also challenged with different inhibitors. The biochemical data allowed us to classify ZsTRYP as a trypsin. Moreover, homology modeling analysis indicated a typical trypsin structural core and a conserved catalytic triad (His(41), Asp(86), and Ser(182)).


Assuntos
Serina Endopeptidases/metabolismo , Gorgulhos/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar , Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Larva/enzimologia , Dados de Sequência Molecular , Dobramento de Proteína , Análise de Sequência de DNA , Serina Endopeptidases/genética , Serina Endopeptidases/isolamento & purificação , Gorgulhos/genética
18.
Artigo em Inglês | MEDLINE | ID: mdl-16406356

RESUMO

Cowpea crops are severely attacked by Callosobruchus maculatus, a Coleopteran that at the larval stage penetrates into stored seeds and feeds on cotyledons. Cowpea weevil control could be based in utilization of bacteria and fungi to reduce pest development. Entomopathogenic fungi, such as Metarhizium anisopliae, are able to control insect-pests and are widely applied in biological control. This report evaluated ten M. anisopliae isolates according to their virulence, correlating chitinolytic, proteolytic and alpha-amylolytic activities, as well proteomic analysis by two dimensional gels of fungal secretions in response to an induced medium containing C. maculatus shells, indicating novel biotechnological tools capable of improving cowpea crop resistance.


Assuntos
Proteínas Fúngicas/farmacologia , Hypocreales/enzimologia , Insetos , Controle Biológico de Vetores , Amidoidrolases/isolamento & purificação , Amidoidrolases/farmacologia , Animais , Quitina/metabolismo , Proteínas Fúngicas/isolamento & purificação , Phaseolus , Proteômica , Serina Endopeptidases/isolamento & purificação , Serina Endopeptidases/farmacologia , alfa-Amilases/metabolismo
19.
Ciênc. rural ; 40(5): 1154-1159, maio 2010. ilus, tab
Artigo em Português | LILACS | ID: lil-552131

RESUMO

Os objetivos deste trabalho foram analisar o perfil proteico do plasma seminal ovino e identificar proteínas relacionadas com a congelabilidade do sêmen que possam ser utilizadas como marcadores para essa característica. Foram utilizados os ejaculados de cinco reprodutores, nos quais foram realizadas avaliações espermáticas e dos quais os plasmas seminais obtidos por centrifugação foram submetidos à eletroforese bidimensional em gel de poliacrilamida. Foram identificados 92 spots, considerando todos os animais analisados. A avaliação dos dados obtidos evidenciou variações significativas nos resultados das análises do sêmen dos animais e uma variabilidade no perfil proteico no plasma seminal dos carneiros. As proteínas 03 (7,9kDa; pI 6,35), 23 (13,6kDa; pI 5,01) e 31 (21,4kDa; pI 4,75) se destacaram, por apresentarem maior expressão e relações com as características espermáticas. Sugere-se que mais estudos sejam realizados para verificar se as proteínas 03, 23 e 31 podem ser utilizadas como marcadores da capacidade criopreservadora do sêmen.


The objective of this study was to analyze the protein profile of ram seminal plasma and to identify proteins associated with semen freezability, which could be used as marker for predicting this feature. Semen from five rams was used. The sperm analysis was held and the seminal plasma obtained by centrifugation was submitted to two-dimensional electrophoresis using acrylamide gel. Ninety two spots were identified considering the analyzed animals. The results showed a significant variation among sperm analysis of the animals and variability in the protein profile of the seminal plasma of the rams. The proteins 03 (7.9kDa; pI 6.35), 23 (13.6kDa; pI 5.01) e 31 (21.4kDa; pI 4.75) stood out because they showed higher expression and because of its relationship with the sperm characteristics. It is suggested more studies to verify if proteins 03, 23 and 31 could be used as markers of semen freezability.

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