Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 232
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Agric Food Chem ; 67(40): 11219-11229, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31408330

RESUMO

Peanut allergy is a major health problem worldwide. Detection of food allergens is a critical aspect of food safety. The VHH domain of single chain antibody from camelids, also known as nanobody (Nb), showed its advantages in the development of biosensors because of its high stability, small molecular size, and ease of production. However, no nanobody specific to peanut allergens has been developed. In this study, we constructed a library with random triplets (NNK) in its CDR regions of a camel nanobody backbone. We screened the library with peanut allergy Ara h 3 and obtained several candidate nanobodies. One of the promising nanobodies, Nb16 was further biochemical characterization by gel filtration, isothermal titration calorimetry (ITC), cocrystallization, and Western blot in terms of its interaction with Ara h 3. Nb16 specifically binds to peanut major allergen Ara h 3 with a dissociation constant of 400 nM. Furthermore, we obtained the Ara h 3-Nb16 complex crystals. Structure analysis shows the packing mode is completely different between the Ara h 3-Nb16 complex crystal and the native Ara h 3 crystal. Structural determination of Ara h 3-Nb16 will provide the necessary information to understand the allergenicity of this important peanut allergen. The nanobody Nb16 may have application in the development of biosensors for peanut allergen detection.


Assuntos
Antígenos de Plantas/imunologia , Arachis/imunologia , Proteínas de Armazenamento de Sementes/imunologia , Anticorpos de Domínio Único/genética , Anticorpos de Domínio Único/imunologia , Sequência de Aminoácidos , Antígenos de Plantas/química , Antígenos de Plantas/genética , Arachis/química , Arachis/genética , Bacteriófagos/genética , Bacteriófagos/metabolismo , Western Blotting , Técnicas de Visualização da Superfície Celular , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/genética , Anticorpos de Domínio Único/análise
2.
J Agric Food Chem ; 67(31): 8626-8631, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31287307

RESUMO

An almond allergen with two known short peptide sequences was reported as the almond 2S albumin but was later suspected to be almond vicilin. However, this allergen was not designated by the World Health Organization/International Union of Immunological Societies. This study aimed to determine the true identity of this elusive almond allergen. cDNAs were synthesized from total RNA of the Nonpareil almond. The complete sequence of the previously reported almond allergen was determined from its coding sequence. The deduced protein was produced recombinantly and was confirmed to be a food allergen by testing with 18 almond-allergic sera. The allergen is a potential cysteine-rich antimicrobial protein with characteristic C[X]3C-[X]10-12-C[X]3C motifs of the hairpinin antimicrobial protein. This first member of a novel family of food allergens was named Pru du 8. The signature motif of the hairpinin antimicrobial protein can be found in the N-terminal region of some vicilin allergens (e.g., Ara h 1). It can also be found in the signal peptide of other vicilin allergens (e.g., Car i 2). In many species, however, vicilins do not contain such a motif, indicating that the presence of the signature motifs of the hairpinin antimicrobial protein in vicilins might be a result of translocation during evolution.


Assuntos
Alérgenos/imunologia , Antígenos de Plantas/imunologia , Prunus dulcis/imunologia , Alérgenos/química , Alérgenos/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Antígenos de Plantas/química , Antígenos de Plantas/genética , DNA Complementar/genética , Hipersensibilidade Alimentar/imunologia , Humanos , Prunus dulcis/química , Prunus dulcis/genética , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/genética , Proteínas de Armazenamento de Sementes/imunologia , Alinhamento de Sequência , Análise de Sequência de DNA
3.
Int J Biol Macromol ; 137: 366-373, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31276718

RESUMO

The noncovalent binding mechanisms between cyanidin-3-O-glucoside (C3G) and two main soy protein fractions: ß-conglycinin (7S) and glycinin (11S) at pH 3.0 were investigated and compared. C3G modified the secondary structure of two fractions by increasing α-helix and random coil content while decreasing ß-sheet content. The binding of C3G also altered the tertiary structure and microenvironment of two fractions, demonstrated by synchronous and three-dimensional fluorescence spectra. Additionally, C3G binding reduced the surface hydrophobicity and thermostability of both 7S and 11S. Moreover, the fluorescence quenching results showed that the binding of C3G to two fractions were spontaneous complexation processes driven by electrostatic forces. The number of C3G bound per protein molecule (n) was near 1. The binding constant (Ka) was 2.41 (±0.42) × 104 M-1 for 11S and 0.81 (±0.01) × 104 M-1 for 7S at 298 K. 11S showed a stronger binding ability for C3G than 7S. These findings contribute to the knowledge of interactions between soy protein fractions and dietary polyphenols under acidic condition, and are beneficial for the application of soy protein-based products in foods.


Assuntos
Antocianinas/metabolismo , Antígenos de Plantas/metabolismo , Globulinas/metabolismo , Glucosídeos/metabolismo , Proteínas de Armazenamento de Sementes/metabolismo , Proteínas de Soja/metabolismo , Antígenos de Plantas/química , Globulinas/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ligação Proteica , Estabilidade Proteica , Estrutura Secundária de Proteína , Proteínas de Armazenamento de Sementes/química , Proteínas de Soja/química , Espectrometria de Fluorescência , Termodinâmica
4.
Food Chem ; 299: 125165, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31306953

RESUMO

In the present study, the antioxidant hydrolysates obtained from watermelon seed protein (WSP) after divergent ultrasound and ultrafiltration treatment were studied. The results showed that the slit divergent ultrasound (SDU, 20/28 KHz) pretreatment had considerable influence on the structure and enzymatic efficiency of WSP. Besides, compared with hydrolysates without ultrasonic and ultrafiltration treatment, watermelon protein hydrolysates with molecular weight <1 kDa (WSPHs-I) showed the highest antioxidant activities and could protect RAW 264.7 cells from H2O2-induced oxidative stress damage via activating the Nrf2/HO-1 pathway. Interestingly, WSPHs-I had good stability against oxidation at temperature under 100 °C or in the acidic or neutral condition and still exhibited strong antioxidant activity after simulated gastrointestinal digestion. Taken together, SDU pretreatment could significantly increase the antioxidant activities and stability of WSPHs by improving the structure and facilitating enzymolysis of the WSP.


Assuntos
Antioxidantes/farmacologia , Citrullus/química , Proteínas de Plantas/química , Hidrolisados de Proteína/farmacologia , Ultrassom/métodos , Animais , Antioxidantes/química , Digestão/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Camundongos , Peso Molecular , Oxirredução , Proteínas de Plantas/farmacologia , Hidrolisados de Proteína/química , Estabilidade Proteica , Células RAW 264.7 , Proteínas de Armazenamento de Sementes/química , Sementes/química , Ultrafiltração
5.
Food Chem ; 293: 299-306, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151615

RESUMO

Quinoa seeds have high protein content and an exceptional balance of amino acids, with higher contents of lysine, methionine and cysteine than common cereals. To date, only three globulins, all of which have a content of lysine mass that does not exceed 3.8%, have been identified in quinoa. To address the protein present in quinoa seeds, TCA/Acetone protein extraction was performed using four different quinoa seed genotypes with contrasting edaphoclimatic origins. Proteins were identified and analyzed using label-free shotgun proteomics followed by in silico analysis, using the three published quinoa genomes. This analysis allowed us to identify sixteen globulins, thirteen of which are novel: nine legumin-like proteins and seven vicilin-like proteins. Seven of the novel proteins contain 7.5% or more of lysine mass, justifying the high content of lysine repeatedly reported in quinoa seeds. No significant differences were found between the four genotypes here analyzed.


Assuntos
Chenopodium quinoa/química , Globulinas/análise , Lisina/análise , Proteínas de Plantas/análise , Proteômica , Proteínas de Armazenamento de Sementes/análise , Chenopodium quinoa/genética , Genoma de Planta , Filogenia , Proteínas de Plantas/química , Proteínas de Armazenamento de Sementes/química
6.
J Agric Food Chem ; 67(22): 6292-6301, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31117486

RESUMO

The development of high-performance nanocarriers for nutraceuticals or drugs has become one of the topical research subjects in the functional food fields. In this work, we for the first time propose a novel and ecofriendly process to obtain a kind of nanostructured soy ß-conglycinin (ß-CG; a major soy storage globulin) as outstanding nanocarriers for poorly soluble bioactives (e.g., curcumin), by a urea-assisted disassembly and reassembly strategy. At urea concentrations > 4 M, the structure of ß-CG gradually dissociated into its separate subunits (α, α', and ß) and even denatured (depending on the type of subunits); after dialysis to remove urea, the dissociated subunits would reassemble into a kind of core-shell nanostructured particles, in which aggregated ß-subunits acted as the core while the shell layer was mainly composed of α- and α'-subunits. The core-shell nanoparticles were favorably formed at protein concentrations of 1.0-2.0 wt %. Curcumin crystals were directly introduced into the ß-CG solution at high urea concentrations (e.g., 8 M) and would preferentially interact with the denatured ß-subunits. As a consequence, almost all of the curcumin molecules were encapsulated in the core part of the reassembled core-shell nanoparticles. The loading amount of curcumin in these nanoparticles could reach 18 g of curcumin per 100 g of protein, which far exceeds those reported previously. The encapsulated curcumin exhibited a high water solubility, extraordinary thermal stability, and improved bioaccessibility, as well as a sustained release behavior. The findings provide a novel strategy to fabricate a kind of high-encapsulation-performance, organic solvent-free, and biocompatible nanocarrier for hydrophobic nutraceuticals and drugs.


Assuntos
Antígenos de Plantas/química , Curcumina/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/instrumentação , Globulinas/química , Proteínas de Armazenamento de Sementes/química , Proteínas de Soja/química , Composição de Medicamentos , Sistemas de Liberação de Medicamentos/métodos , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas/química , Tamanho da Partícula , Solubilidade , Soja/química
7.
ACS Chem Biol ; 14(5): 979-993, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-30973714

RESUMO

New proteins can evolve by duplication and divergence or de novo, from previously noncoding DNA. A recently observed mechanism is for peptides to evolve within a "host" protein and emerge by proteolytic processing. The first examples of such interstitial peptides were ones hosted by precursors for seed storage albumin. Interstitial peptides have also been observed in precursors for seed vicilins, but current evidence for vicilin-buried peptides (VBPs) is limited to seeds of the broadleaf plants pumpkin and macadamia. Here, an extensive sequence analysis of vicilin precursors suggested that peptides buried within the N-terminal region of preprovicilins are widespread and truly ancient. Gene sequences indicative of interstitial peptides were found in species from Amborellales to eudicots and include important grass and legume crop species. We show the first protein evidence for a monocot VBP in date palm seeds as well as protein evidence from other crops including the common tomato, sesame and pumpkin relatives, cucumber, and the sponge loofah ( Luffa aegyptiaca). Their excision was consistent with asparaginyl endopeptidase-mediated maturation, and sequences were confirmed by tandem mass spectrometry. Our findings suggest that the family is large and ancient and that based on the NMR solution structures for loofah Luffin P1 and tomato VBP-8, VBPs adopt a helical hairpin fold stapled by two internal disulfide bonds. The first VBPs characterized were a protease inhibitor, antimicrobials, and a ribosome inactivator. The age and evolutionary retention of this peptide family suggest its members play important roles in plant biology.


Assuntos
Proteínas de Armazenamento de Sementes/química , Sequência de Aminoácidos , Proteólise , Homologia de Sequência de Aminoácidos , Espectrometria de Massas em Tandem
8.
J Agric Food Chem ; 67(8): 2201-2211, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30719912

RESUMO

Soybean protein exhibits nutritional significance for the control of metabolic syndrome, and evidence suggests that gut microbiota are implicated in the control of metabolic disorders. This study aimed to investigate the modulation of pepsin-released peptides of soybean 7S globulin on gut microbiota and possible association between changes of gut microbiota composition and lipopolysaccharide (LPS)-peptide interaction. In vitro fermentation experiments showed that the extension region (ER) fragments of soybean 7S globulin selectively suppressed proinflammatory Gram-negative bacteria. ER peptides also promoted the highest production of short-chain fatty acids (SCFAs), which were associated with increase of the relative abundance of Lachnospiraceae and Lactobacillaceae. Isothermal titration calorimetry (ITC) and Langmuir monolayer studies demonstrated that ER peptides exhibited high affinity to LPS in the presence of Ca2+ and developed into ß-sheet-rich aggregate structures, thus weakening the stability of LPS monolayers. This finding supplies a possible explanation for improvement of the effects of soybean 7S globulin on metabolic disease.


Assuntos
Antígenos de Plantas/metabolismo , Microbioma Gastrointestinal , Globulinas/metabolismo , Lipopolissacarídeos/metabolismo , Peptídeos/metabolismo , Proteínas de Armazenamento de Sementes/metabolismo , Proteínas de Soja/metabolismo , Antígenos de Plantas/química , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Ácidos Graxos Voláteis/metabolismo , Fezes/microbiologia , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Globulinas/química , Humanos , Lipopolissacarídeos/química , Peptídeos/química , Proteínas de Armazenamento de Sementes/química , Proteínas de Soja/química
9.
J Sci Food Agric ; 99(8): 4011-4018, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30723906

RESUMO

BACKGROUND: Lupin-based food, due to the high content of functional proteins and phenolic compounds, are widely used in human nutrition. Unfortunately, proteins and phenolic compounds can easily interact with each other which results in formation of complexes that affect properties of both components. Therefore, in this study, composition of the seeds storage proteins isolated from Lupinus albus and L. angustifolius and their interactions with native flavonoids were investigated. RESULTS: Based on the chromatographic separations, six proteins fractions of lupin seeds storage proteins were identified. The results indicate that two dominant fractions, α-conglutin and ß-conglutin, constitute up to 80% of all proteins present in the seeds. Three flavonoids interacting with the proteins were identified as apigenin C-glycosides. The lowest flavonoids content was noted in the main storage proteins while in both lupin seeds species over 90% of flavonoids interacted with the proteins present in late-embryogenesis abundant (LEA) protein fraction. CONCLUSIONS: Protein-phenolic compound complexes can affect the digestibility of proteins and bioavailability of phenolic compounds, and thus the functional and nutritional properties of products derived from lupin seeds can be changed. Therefore, a better understanding of factors affecting the nutritional value of lupin seeds proteins and flavonoids is necessary to optimize the biological use of this plant for human nutrition. © 2019 Society of Chemical Industry.


Assuntos
Flavonoides/metabolismo , Lupinus/metabolismo , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/metabolismo , Flavonoides/química , Lupinus/química , Fenóis/química , Fenóis/metabolismo , Ligação Proteica , Proteínas de Armazenamento de Sementes/isolamento & purificação , Sementes/química , Sementes/metabolismo
10.
Nutrients ; 11(2)2019 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-30791360

RESUMO

The protein fractions of cocoa have been implicated influencing both the bioactive potential and sensory properties of cocoa and cocoa products. The objective of the present review is to show the impact of different stages of cultivation and processing with regard to the changes induced in the protein fractions. Special focus has been laid on the major seed storage proteins throughout the different stages of processing. The study starts with classical introduction of the extraction and the characterization methods used, while addressing classification approaches of cocoa proteins evolved during the timeline. The changes in protein composition during ripening and maturation of cocoa seeds, together with the possible modifications during the post-harvest processing (fermentation, drying, and roasting), have been documented. Finally, the bioactive potential arising directly or indirectly from cocoa proteins has been elucidated. The "state of the art" suggests that exploration of other potentially bioactive components in cocoa needs to be undertaken, while considering the complexity of reaction products occurring during the roasting phase of the post-harvest processing. Finally, the utilization of partially processed cocoa beans (e.g., fermented, conciliatory thermal treatment) can be recommended, providing a large reservoir of bioactive potentials arising from the protein components that could be instrumented in functionalizing foods.


Assuntos
Cacau/química , Chocolate , Manipulação de Alimentos/métodos , Peptídeos/farmacologia , Proteínas de Armazenamento de Sementes/química , Sementes/química , Animais , Dessecação , Fermentação , Temperatura Alta , Humanos , Peptídeos/uso terapêutico , Polifenóis/farmacologia , Polifenóis/uso terapêutico
11.
Food Chem ; 272: 201-209, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30309533

RESUMO

The effects of selenium (Se) on the protein content, amino acid profile, secondary structure and subunit composition of soy proteins and its distribution were evaluated, as was the effect of peroxyl radicals produced by thermal decomposition of AAPH on the conformational changes of Se-enriched ß-conglycinin (S-7S). The Se biofortification ability of soy was very strong, 7S had strongest ability to incorporate Se, and lower amounts of inorganic Se existed in Se-enriched beans. Se could promote protein synthesis and thus improve the protein content, increase the total amino acid content with a decrease in cysteine, combine into low-molecular-weight proteins, and influence the secondary structure of soybean proteins. Se was involved in the relevant protein changes in surface hydrophobicity, intrinsic fluorescence, infrared absorption and solubility and played an antioxidant role as an effectual "protector" to reduce the influence of peroxyl radical oxidation on S-7S, thereby maintaining the structural rearrangement between aggregation and protein unfolding.


Assuntos
Amidinas/farmacologia , Antígenos de Plantas/química , Antígenos de Plantas/farmacologia , Globulinas/química , Globulinas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/farmacologia , Selênio/análise , Proteínas de Soja/química , Proteínas de Soja/farmacologia , Peso Molecular , Estrutura Secundária de Proteína
12.
J Agric Food Chem ; 67(1): 425-432, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30512943

RESUMO

Almond is one of the tree nuts listed by U.S. FDA as a food allergen source. A food allergen identified with patient sera has been debated to be the 2S albumin or the 7S vicilin. However, neither of these proteins has been defined as a food allergen. The purpose of this study was to clone, express, and purify almond vicilin and test whether it is a food allergen. Western blot experiment was performed with 18 individual sera from patients with double-blind, placebo-controlled clinical almond allergy. The results showed that 44% of the sera contained IgE antibodies that recognized the recombinant almond vicilin, indicating that it is an almond allergen. Identifying this and additional almond allergens will facilitate the understanding of the allergenicity of seed proteins in tree nuts and their cross-reactivity.


Assuntos
Antígenos de Plantas/imunologia , Hipersensibilidade Alimentar/imunologia , Prunus dulcis/imunologia , Proteínas de Armazenamento de Sementes/imunologia , Sequência de Aminoácidos , Antígenos de Plantas/química , Antígenos de Plantas/genética , Reações Cruzadas , Hipersensibilidade Alimentar/sangue , Humanos , Imunoglobulina E/imunologia , Dados de Sequência Molecular , Prunus dulcis/química , Prunus dulcis/genética , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/genética , Sementes/química , Sementes/genética , Sementes/imunologia , Alinhamento de Sequência
13.
Molecules ; 24(1)2018 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-30585221

RESUMO

Gly m 5.0101, the alpha subunit of ß-conglycinin, is one of the major allergens found in soybeans that has been identified as causing an allergic reaction. Here, we developed a quantification method of Gly m 5.0101 with multiple reaction monitoring using the synthetic peptide 194NPFLFGSNR202 as the external standard. Firstly, the ground soybean was defatted and extracted with a protein extraction buffer. Then the crude extract was on-filter digested by trypsin and analyzed by liquid chromatography-tandem mass spectrometry. The selected peptide exhibited a detection limit of 0.48 ng/mL and a linear relationship in a concentration range from 1.6 to 500 ng/mL (r² > 0.99). The developed method was successfully applied to quantify the Gly m 5.0101 level in dozens of soybean varieties from different sources and soybean products derived from different processing techniques. The developed method could be used to further analyze ß-conglycinin in soybean seeds combined with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis.


Assuntos
Antígenos de Plantas/análise , Globulinas/análise , Proteínas de Armazenamento de Sementes/análise , Proteínas de Soja/análise , Soja/química , Alérgenos/análise , Alérgenos/química , Antígenos de Plantas/química , Cromatografia Líquida de Alta Pressão , Globulinas/química , Subunidades Proteicas/análise , Proteínas de Armazenamento de Sementes/química , Sementes/química , Proteínas de Soja/química , Espectrometria de Massas em Tandem
14.
Molecules ; 23(12)2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30544764

RESUMO

The soy protein isolates (SPI) extracted from different extruded full-fat soybean flakes (FFSF), and their conformational and functional properties were characterized. Overall, the free thiol (SH) content of SPI increased when the extrusion temperature was below 80 °C and decreased at higher temperatures. Soy glycinin (11S) showed higher stability than ß-conglycinin (7S) during extrusion. Results also indicated that the increase in some hydrophobic groups was due to the movement of hydrophobic groups from the interior to the surface of the SPI molecules at extrusion temperatures from 60 to 80 °C. However, the aggregation of SPI molecules occurred at extrusion temperatures of 90 and 100 °C, with decreasing levels of hydrophobic groups. The extrusion temperature negatively affected the emulsifying activity index (EAI); on the other side, it positively affected the emulsifying stability index (ESI), compared to unextruded SPI.


Assuntos
Proteínas de Soja/química , Proteínas de Soja/isolamento & purificação , Soja/metabolismo , Antígenos de Plantas/química , Antígenos de Plantas/isolamento & purificação , Antígenos de Plantas/metabolismo , Temperatura Baixa , Globulinas/química , Globulinas/isolamento & purificação , Globulinas/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Peso Molecular , Estabilidade Proteica , Estrutura Secundária de Proteína , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/isolamento & purificação , Proteínas de Armazenamento de Sementes/metabolismo , Proteínas de Soja/metabolismo , Compostos de Sulfidrila/análise
15.
J Agric Food Chem ; 66(48): 12617-12626, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30403850

RESUMO

Faba bean ( Vicia faba L.) is one of the foremost candidate crops for simultaneously increasing both sustainability and global supply of plant protein. On a dry matter basis, its seeds contain about 29% protein of which more than 80% consists of globulin storage proteins (vicilin and legumin). However, to achieve optimum utilization of this crop for human and animal nutrition, both protein content and quality have to be improved. Though initial investigations on the heritability of these traits indicated the possibility for genetic improvement, little has been achieved so far, partly due to the lack of genetic information coupled with the complex relationship between protein content and grain yield. This review reports on the current knowledge on Vicia faba seed storage proteins, their structure, composition, and genetic control, and highlights key areas for further improvement of the content and composition of Vicia faba seed storage proteins on the basis of recent advances in Vicia faba genome knowledge and genetic tools.


Assuntos
Proteínas de Armazenamento de Sementes/genética , Vicia faba/genética , Variação Genética , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/metabolismo , Sementes/química , Sementes/genética , Sementes/metabolismo , Vicia faba/química , Vicia faba/metabolismo
16.
ACS Appl Mater Interfaces ; 10(48): 41056-41069, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30387987

RESUMO

Intracellular activation of nanomaterials within cancer cells presents a powerful means to enhance anticancer specificity and efficacy. In light of upregulated lysosomal protease cathepsin-B (CathB) in many types of invasive cancer cells, herein, we exploit CathB-catalyzed biodegradation of acetylated rapeseed protein isolate (ARPI) to design polymer-drug nanocomplexes that can produce proapoptotic peptides in situ and synergize chemotherapy. ARPI forms nanocomplexes with chitosan (CS) and anticancer drug doxorubicin (DOX) [DOX-ARPI/CS nanoparticles (NPs)] by ionic self-assembly. The dual acidic pH- and CathB-responsive properties of the nanocomplexes and CathB-catalyzed biodegradation of ARPI enable efficient lysosomal escape and nuclei trafficking of released DOX, resulting in elevated cytotoxicity in CathB-overexpressing breast cancer cells. The ARPI-derived bioactive peptides exhibit synergistic anticancer effect with DOX by regulating pro- and antiapoptotic-relevant proteins ( p53, Bax, Bcl-2, pro-caspase-3) at mitochondria. In an orthotopic breast tumor model of CathB-overexpressing breast cancer, DOX-ARPI/CS NPs remarkably inhibit tumor growth, enhance tumor cell apoptosis and prolong host survival without eliciting any systemic toxicity. These results suggest that exploitation of multifunctional biomaterials to specifically produce anticancer agents inside cancer cells and trigger drug release to the subcellular target sites is a promising strategy for designing effective synergistic nanomedicines with minimal off-target toxicity.


Assuntos
Brassica rapa/química , Neoplasias da Mama , Catepsina B/biossíntese , Doxorrubicina , Portadores de Fármacos , Nanoestruturas , Proteínas de Neoplasias/metabolismo , Proteínas de Armazenamento de Sementes , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Feminino , Humanos , Células MCF-7 , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/farmacocinética , Proteínas de Armazenamento de Sementes/farmacologia
17.
J Agric Food Chem ; 66(40): 10552-10557, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30226051

RESUMO

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is involved in cholesterol homeostasis, because it induces the low-density lipoprotein receptor (LDLR) degradation. This protein may carry some positive or negative mutations: PCSK9D374Y is one of the most dangerous gain-of-function mutations. This paper reports the identification of the first food-derived peptide able to inhibit the protein-protein interaction (PPI) between PCSK9D374Y and LDLR. In fact, T9 (GQEQSHQDEGVIVR), an absorbable peptide deriving from lupin ß-conglutin, is able to impair the PPI between PCSK9D374Y and the LDLR, with an IC50 value equal to 285.6 ± 2.46 µM. The consequence of this inhibition is an increase of the protein level of the LDLR located on hepatic cell membranes up to 74.3 ± 4.4% and the restoration of the functional capability of HepG2 cells to uptake extracellular low-density lipoprotein up to 83.1 ± 1.6%. Finally, the putative binding mode of T9 to the LDLR binding site located on PCSK9D374Y was postulated by in silico tools.


Assuntos
Mutação com Ganho de Função , Peptídeos/química , Pró-Proteína Convertase 9/química , Pró-Proteína Convertase 9/genética , Receptores de LDL/química , Proteínas de Armazenamento de Sementes/química , Sítios de Ligação , Células Hep G2 , Humanos , Modelos Moleculares , Peptídeos/metabolismo , Pró-Proteína Convertase 9/metabolismo , Ligação Proteica , Receptores de LDL/genética , Receptores de LDL/metabolismo
18.
Biochem J ; 475(19): 3057-3071, 2018 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-30181145

RESUMO

Proteins belonging to cupin superfamily are known to have critical and diverse physiological functions. However, 7S globulins family, which is also a part of cupin superfamily, were undermined as only seed storage proteins. Structure determination of native protein - Vic_CAPAN from Capsicum annuum - was carried out, and its physiological functions were explored after purifying the protein by ammonium sulfate precipitation followed by size exclusion chromatography. The crystal structure of vicilin determined at 2.16 Šresolution revealed two monomers per asymmetric unit which are juxtaposed orthogonal with each other. Vic_CAPAN consists predominately of ß-sheets that folds to form a ß-barrel structure commonly called cupin fold. Each monomer of Vic_CAPAN consists of two cupin fold domains, N-terminal and C-terminal, which accommodate two different ligands. A bound ligand was identified at the C-terminal cupin fold in the site presumably conserved for metabolites in the crystal structure. The ligand was confirmed to be salicylic acid through mass spectrometric analysis. A copper-binding site was further observed near the conserved ligand-binding pocket, suggesting possible superoxide dismutase activity of Vic_CAPAN which was subsequently confirmed biochemically. Vicilins from other sources did not exhibit this activity indicating functional specificity of Vic_CAPAN. Discovery of bound salicylic acid, which is a known regulator of antioxidant pathway, and revelation of superoxide dismutase activity suggest that Vic_CAPAN has an important role during oxidative stress. As salicylic acid changes the redox state of cell, it may act as a downstream signal for various pathways involved in plant biotic and abiotic stress rescue.


Assuntos
Capsicum , Estresse Oxidativo/fisiologia , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/metabolismo , Sequência de Aminoácidos , Sítios de Ligação/fisiologia , Cristalização , Extratos Vegetais/genética , Estrutura Secundária de Proteína , Proteínas de Armazenamento de Sementes/genética , Sementes
19.
Food Chem ; 268: 315-323, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30064764

RESUMO

The study aimed at improving the antioxidant activity of ß-conglycinin to enhance the oxidative and physical stabilities of safflower oil-in-water emulsion stabilized by ß-conglycinin. Heating promoted binding affinity and antioxidant activity of ß-conglycinin. Catechin and chlorogenic acid showed higher binding affinities towards unheated (or heated) ß-conglycinin than caffeic acid and quercetin. The enhancement efficiencies of the phenolics on the antioxidant activity of unheated (or heated) ß-conglycinin decreased in the order of catechin > quercetin > chlorogenic acid > caffeic acid. Hydrophobic force and hydrogen bonding were the important binding forces for the selected phenolics to ß-conglycinin. The complexation with catechin has no side effect on interfacial behavior and emulsifying property of ß-conglycinin. The use of heated ß-conglycinin-catechin complex as an emulsifier for preparing safflower oil emulsion effectively improved the oxidative and physical stabilities of the emulsion treated with lipoxygenase through inhibition of lipid oxidation, protein carbonyl formation and sulfhydryl loss.


Assuntos
Antígenos de Plantas/química , Antioxidantes/química , Catequina/química , Emulsões/química , Globulinas/química , Proteínas de Armazenamento de Sementes/química , Proteínas de Soja/química , Antígenos de Plantas/metabolismo , Catequina/metabolismo , Globulinas/metabolismo , Peroxidação de Lipídeos , Lipoxigenases/metabolismo , Oxirredução , Ligação Proteica , Carbonilação Proteica , Óleo de Açafrão/química , Proteínas de Armazenamento de Sementes/metabolismo , Proteínas de Soja/metabolismo , Espectrometria de Fluorescência , Compostos de Sulfidrila/química , Água/química
20.
Food Res Int ; 111: 574-581, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30007720

RESUMO

Food-derived opioid peptides that are released from proteins by digestion, fermentation, or food production processes lead to several health problems. The opioids are generally resistant to hydrolyze by proteases, except the dipeptidyl peptidase IV (DPPIV, EC 3.4.14.5) enzyme, because of proline amino acid. ß-casomorphin (BCM) from milk casein, gluteomorphin (GM) from wheat gluten, and soymorphin (SM) from the soybean ß-conglycinin ß-subunit are natural substrates of DPPIV because of their amino acid sequences and proline location. In the present study, DPPIV from Lactococcus lactis spp. lactis was purified and characterized by mass spectrometry. Purified DPPIV was added to standard BCM, GM, and SM, and hydrolysis percentages of morphins were measured by HPLC analysis. The results indicated that DPPIV enzyme hydrolyzed food-derived opioids (from 0.1 mM to 2 mM), BCM (33.42% for 2 mM), SM (83.81% for 2 mM), and GM (45.73% for 2 mM) in vitro. Hydrolysis percentages of SM were considerably higher than the same concentrations with BCM and GM. For dietary supplements to be promising for reducing the adverse effects of food derived opioids, this must be supported by in vivo studies of DPPIV use in the human body.


Assuntos
Analgésicos Opioides/química , Dipeptidil Peptidase 4/metabolismo , Lactococcus lactis/enzimologia , Animais , Antígenos de Plantas/química , Caseínas/química , Endorfinas/química , Globulinas/química , Glutens/química , Hidrólise , Peso Molecular , Derivados da Morfina/química , Fragmentos de Peptídeos/química , Proteínas de Armazenamento de Sementes/química , Proteínas de Soja/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA