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1.
Food Chem ; 305: 125500, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31525593

RESUMO

The influences of folding patterns on the protein polymerization in dumpling wrappers were investigated. The dumpling dough sheet after the compounding rollers was folded with various patterns (control with no angle, 15°, 25°, 35° and 45° folding), before going through the sheeting and reduction rolls. Protein secondary structure, free sulfhydryl content, protein electrophoretic profiles, and texture of dumpling wrappers were determined. Results showed that folding could increase the proportion of α-helix conformation, and produce dumpling wrappers with enhanced toughness but reduce wrapper extensibility. The wrapper with 45° folding showed lower -SH content than the control and other folding angles. However, only a few variations in SDS band pattern and intensities were observed at the molecular weight position of around 35 kDa. Briefly, folding process could influence the gluten formation during the preparation of dumpling wrappers; the folding angle at 45° produced stronger gluten network and tougher wrappers.


Assuntos
Farinha , Alimentos , Proteínas de Plantas/química , Multimerização Proteica , Triticum/química , Glutens/química , Peso Molecular , Estrutura Quaternária de Proteína
2.
Food Chem ; 305: 125484, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514048

RESUMO

Grape pathogenesis-related proteins can cause haze in wine that is undesirable for consumers. Bentonite is used to remove these proteins but is a non-renewable natural material and reduces wine volume due to poor settling. As a potential bentonite alternative, grape seeds powder (GSP) was added to four wines and two grape juice varieties. Addition to wine required high doses (25-32 g/L) for protein removal and haze prevention and this induced changes to wine composition. By contrast, addition to grape juice prior to fermentation required substantially lower doses of GSP (5 g/L) to prevent haze formation. Further 20 g/L of GSP added to the must induced less changes to wine composition than direct addition of GSP to the wine. No changes were recorded in the efficacy of protein removal by changing the GSP source (red or white grape marc), or by using grape seed roasting. Despite the need for additional trials, these preliminary results suggest that GSP may be considered as a viable alternative to bentonite especially when added to juice prior to fermentation.


Assuntos
Pós/química , Vitis/química , Adsorção , Bentonita/química , Cor , Estudos de Viabilidade , Qualidade dos Alimentos , Sucos de Frutas e Vegetais/análise , Proteínas de Plantas/química , Sementes/química , Sementes/metabolismo , Vitis/metabolismo , Vinho/análise
3.
J Agric Food Chem ; 67(46): 12895-12903, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31682429

RESUMO

Genipin, a natural electrophilic cross-linker, was applied (5, 10, 20, and 30 mM) to modify hempseed protein isolate (HPI). Genipin treatments resulted in general losses of total sulfhydryls (up to 2.9 nmol/mg) and free amines (up to 77.3 nmol/mg). Surface hydrophobicity decreased by nearly 90% with 30 mM genipin, corresponding to similar tryptophan fluorescence quenching. The genipin treatment converted HPI into highly cross-linked polymers. Hydrogels formed with such polymers when also incorporated with hemp oil emulsions exhibited substantially enhanced gelling ability: up to 3.3- and 2.6-fold increases, respectively, in gel strength and gel elasticity over genipin-untreated protein. The genipin-modified composite gels also exhibited superior water-holding capacity. Microstructural analysis revealed a compact gel network filled with protein-coated oil globules that interacted intimately with the protein matrix when treated with genipin. Such gels remained readily digestible. Hence, genipin-treated hemp protein hydrogels show promise as functional food components.


Assuntos
Cannabis/química , Hidrogéis/química , Iridoides/química , Proteínas de Plantas/química , Reagentes para Ligações Cruzadas/química , Emulsões/química , Reologia , Sementes/química
4.
Protein Pept Lett ; 26(10): 768-775, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618171

RESUMO

INTRODUCTION: Metallothioneins (MTs) are members of a family of low molecular weight and cysteine-rich proteins that are involved in heavy metal homeostasis and detoxification in living organisms. Plants have multiple MT types that are generally divided into four subgroups according to the arrangement of Cys residues. METHODS: In the present study the E. coli cells which heterologously express four different rice MT (OsMT) isoforms were analyzed for the accumulation of two forms of chromium, Cr3+ and Cr6+. RESULTS: The results show that the transgenic bacteria were more tolerant than control cells when they were grown up in the medium comprising Cr(NO3)3.9H2O or Na2CrO4. The cells expressing OsMT1, OsMT2, OsMT3 and OsMT4 give rise to 6.5-, 2.7-, 5.5- and 2.1-fold improvements on the accumulation capacity for Cr3+ and 9-, 3-, 5- and 3- fold Cr6+ respectively compared with comparison to the control strain. Furthermore, the purified recombinant GST-OsMTs were tested for their binding ability to Cr+3 and Cr+6 in vitro. DISCUSSION: The data show that the recombinant GST-OsMT1 and GST-OsMT2 were able to bind both Cr3+ and Cr6+, in vitro. However, their binding strength was low with respect to previous tested divalent ions like Cd2+.


Assuntos
Cromo/química , Metalotioneína/química , Oryza/química , Proteínas de Plantas/química , Proteínas Recombinantes/química , Sequência de Aminoácidos , Cátions/química , Cisteína/química , Escherichia coli/genética , Concentração de Íons de Hidrogênio , Metalotioneína/genética , Proteínas de Plantas/genética , Ligação Proteica , Isoformas de Proteínas , Proteínas Recombinantes/genética
5.
J Agric Food Chem ; 67(44): 12255-12263, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31618580

RESUMO

Jujube (Ziziphus jujuba Mill.) honey, one of the most valuable honey varieties from China with unique characteristics, is vulnerable to being the target of adulteration and deliberate mislabeling of botanical origin. This study investigated the typical protein component of jujube honey to authenticate the floral source by SDS-PAGE analysis combined with LC-MS/MS identification, and its stability to heating was also evaluated. One band and two adjacent but independent bands, both with molecular weights of ∼19 kDa, were notably observed in Coomassie brilliant blue- and silver-stained SDS-PAGE gels, respectively, for jujube honey from different geographic origins, whereas that was not present for the other five botanical honey varieties, suggesting this protein component was suitable as a marker for jujube honey. LC-MS/MS identification revealed that it was constituted by one Z. jujuba-derived protein (gene number:Zj.jz016003045) and two A. mellifera-derived proteins (an uncharacterized protein with accession number tr|A0A088AC16 and a cleavage fragment from major royal jelly protein-1), and the existence of plant-derived protein was attributed to the special neutral pH of jujube honey. Additionally, these protein markers exhibited good stability to heating below 85 °C/30 min. This study provided a simple method to characterize jujube honey and first identified a protein indicator to determine the botanical origin of honey.


Assuntos
Proteínas de Plantas/química , Ziziphus/química , Sequência de Aminoácidos , China , Cromatografia Líquida , Eletroforese em Gel de Poliacrilamida , Frutas/química , Frutas/genética , Mel/análise , Peso Molecular , Proteínas de Plantas/genética , Espectrometria de Massas em Tandem , Ziziphus/genética
6.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3594-3600, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602928

RESUMO

Cytochrome P450 family is a kind of biocatalyst widely existing in nature. It has many functions such as catalyzing the biosynthesis of plant secondary metabolites and regulating phytoremediation. Based on the analysis of proteome data of Tripterygium wilfordii,the CYP450 gene of T. wilfordii was preliminarily analyzed and predicted by various bioinformatics methods. The results showed that after the expression of T. wilfordii suspension cells was induced by methyl jasmonate,the proteomic data of T. wilfordii were obtained and analyzed,and 10 CYP450 proteins of T. wilfordii were finally screened out. By analyzing the phylogenetic tree constructed with CYP450 gene of Arabidopsis family,the 10 CYP450 proteins were clustered into 6 different CYP450 families. The physical and chemical properties of CYP450 proteins in different families were different. The secondary structure of CYP450 proteins was mainly composed of irregular curls. Eight subcellular localization results of CYP450 proteins were chloroplasts and the rest were plastids. Subsequently,the conserved domains( heme active sites) shared by CYP450 genes were found by analyzing the results of multiple sequence alignment. Finally,by analyzing the transcriptome data of T. wilfordii,the expression distribution of T. wilfordii in different tissues was preliminarily confirmed,which verified its correlation with the biosynthesis of active components of T. wilfordii,and provided important genetic resources for the analysis of biosynthesis pathway of active components of T. wilfordii.


Assuntos
Sistema Enzimático do Citocromo P-450/química , Proteínas de Plantas/química , Tripterygium/enzimologia , Biologia Computacional , Filogenia , Proteômica , Distribuição Tecidual
7.
J Agric Food Chem ; 67(44): 12219-12227, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31613626

RESUMO

Quantification, using an accurate analytical approach, of capsinoids and capsaicinoids was performed on three chili pepper (Capsicum spp.) genotypes: "Chiltepín", "Tampiqueño 74", and "Bhut Jolokia" at various stages of fruit development. The accumulation of capsinoids, in all these peppers started between 10 to 20 days post-anthesis (dpa), increased and reached the highest capsinoid amount at 40 dpa, and then decreased until 60 dpa. Conversely, capsaicinoids could already be determined at 10 dpa in "Bhut Jolokia" and their accumulation pattern was different from that of the capsinoids in this genotype. The capsiate/dihydrocapsiate ratio presented a higher variation between genotypes and developmental stages than the capsaicin/dihydrocapsaicin ratio. Capsinoid ratios (4-24%) and Pun1/pAMT genotyping were determined. These results provide information on the progress of the accumulation of capsinoids in the aforementioned pungent and superhot cultivars and could support future breeding studies toward the understanding of the factors affecting their accumulation.


Assuntos
Capsaicina/análogos & derivados , Capsaicina/metabolismo , Capsicum/genética , Capsicum/metabolismo , Aromatizantes/metabolismo , Frutas/crescimento & desenvolvimento , Proteínas de Plantas/genética , Alelos , Sequência de Aminoácidos , Capsaicina/análise , Capsicum/química , Capsicum/crescimento & desenvolvimento , Aromatizantes/análise , Frutas/química , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Genótipo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência
8.
J Agric Food Chem ; 67(42): 11568-11576, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31584809

RESUMO

Tribenuron-methyl (TM), as one of the sulfonylurea (SU) herbicides, has been widely and effectively applied for many kinds of plants. SUs inhibit plant growth by restraining the biosynthetic pathway of branched-chain amino acids (BCAAs) catalyzed by acetolactate synthase (ALS). Safeners are agrochemicals that protect crops from herbicide injuries. To improve the crop tolerance under TM toxicity stress, this paper evaluated the protective effect of N-tosyloxazolidine-3-carboxamide. It turned out that most of the tested compounds showed significant protection against TM via enhancing the glutathione (GSH) content and glutathione S-transferase (GST) activity. Among all of the tested compounds, compound 16 exhibited more excellent protection than the contrast safener R-28725 and other target compounds. A positive correlation between the growth level, endogenous GSH content, and GST activity was observed in this research. The GST kinetic parameter Vmax of the maize was increased by 29.6% after treatment with compound 16, while Km was decreased by 51.9% compared to the untreated control. The molecular docking model indicated that compound 16 could compete with TM in the active site of ALS, which could interpret the protective effects of safeners. The present work demonstrated that N-tosyloxazolidine-3-carboxamide derivatives could be considered as potential candidates for developing new safeners in the future.


Assuntos
Herbicidas/toxicidade , Proteínas de Plantas/metabolismo , Substâncias Protetoras/farmacologia , Zea mays/efeitos dos fármacos , Zea mays/enzimologia , Acetolactato Sintase/química , Acetolactato Sintase/metabolismo , Glutationa Transferase/química , Glutationa Transferase/metabolismo , Cinética , Simulação de Acoplamento Molecular , Proteínas de Plantas/química , Compostos de Sulfonilureia/toxicidade , Zea mays/química
9.
J Agric Food Chem ; 67(45): 12382-12392, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31635461

RESUMO

Protoporphyrinogen oxidase (PPO, EC 1.3.3.4) is a promising target for herbicide discovery. Search for new compounds with novel chemotypes is a key objective for agrochemists. Here, we describe the discovery and systematic SAR-based structure optimization of novel N-isoxazolinylphenyltriazinones 5-9 as PPO inhibitors. The in vivo herbicidal activity and in vitro Nicotiana tabacum PPO (NtPPO) inhibitory activity were explored in detail. A number of the new synthetic compounds displayed strong PPO inhibitory activity with Ki values in the nanomolar range. Some compounds exhibited excellent and broad-spectrum weed control at the rate of 9.375-37.5 g ai/ha by postemergence application and showed improved monocotyledonous weed control compared to saflufenacil. Most promisingly, ethyl 3-(2-chloro-5-(3,5-dimethyl-2,6-dioxo-4-thioxo-1,3,5-triazinan-1-yl)-4-fluorophenyl)-5-methyl-4,5-dihydroisoxazole-5-carboxylate, 5a, with a Ki value of 4.9 nM, displayed over 2- and 6-fold higher potency than saflufenacil (Ki = 10 nM) and trifludimoxazin (Ki = 31 nM), respectively. Moreover, 5a showed excellent and broad-spectrum weed control against 32 kinds of weeds at 37.5-75 g ai/ha. Rice exhibited relative tolerance to 5a at 150 g ai/ha by postemergence application, indicating that 5a could be a potential herbicide candidate for weed control in paddy fields.


Assuntos
Inibidores Enzimáticos/farmacologia , Herbicidas/química , Herbicidas/farmacologia , Proteínas de Plantas/antagonistas & inibidores , Protoporfirinogênio Oxidase/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos/química , Cinética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Daninhas/química , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/enzimologia , Protoporfirinogênio Oxidase/química , Protoporfirinogênio Oxidase/metabolismo , Relação Quantitativa Estrutura-Atividade , Tabaco/química , Tabaco/efeitos dos fármacos , Tabaco/enzimologia , Controle de Plantas Daninhas
10.
J Agric Food Chem ; 67(42): 11694-11702, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31558015

RESUMO

Sucrose synthase (SUS) plays an important role in carbohydrate metabolism in plants. The SUS genes in licorice remain unknown. To reveal the sucrose metabolic pathway in licorice, all the 12 putative SUS genes of Glycyrrhiza uralensis were systematically identified by genome mining, and two novel SUSs (GuSUS1 and GuSUS2) were isolated and characterized for the first time. Furthermore, we found that the flexible N-terminus was responsible for the low stability of plant SUSs, and deletion of redundant N-terminus improved the stability of GuSUS1 and GuSUS2. The half-life of both GuSUS1 and GuSUS2 mutants was increased by 2-fold. Finally, the GuSUS1 mutant was coupled with UGT73C11 for the glycosylation of glycyrrhetinic acid (GA) with uridine 5'-diphosphate disodium salt hydrate (UDP) in situ recycling, and GA conversion was increased by 7-fold. Our study not only identified the SUS genes in licorice but also provided a stable SUS mutant for the construction of an efficient UDP-recycling system for GA glycosylation.


Assuntos
Glucosiltransferases/metabolismo , Glycyrrhiza uralensis/enzimologia , Proteínas de Plantas/metabolismo , Difosfato de Uridina/metabolismo , Biocatálise , Glucosiltransferases/química , Glucosiltransferases/genética , Glicosilação , Ácido Glicirretínico/metabolismo , Glycyrrhiza uralensis/química , Glycyrrhiza uralensis/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Difosfato de Uridina/química
11.
J Agric Food Chem ; 67(37): 10423-10431, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31487168

RESUMO

Plants often produce antifungal peptides and proteins in response to infection. Also wheat, which is the main ingredient of bread dough, contains such components. Here, we show that while some industrial strains of the baker's yeast Saccharomyces cerevisiae can efficiently ferment dough, some other strains show much lower fermentation capacities because they are sensitive to a specific wheat protein. We purified and identified what turned out to be a thaumatin-like protein through a combination of activity-guided fractionation, cation exchange chromatography, reversed-phase HPLC, and LC-MS/MS. Recombinant expression of the corresponding gene and testing the activity confirmed the inhibitory activity of the protein.


Assuntos
Proteínas de Plantas/química , Proteínas de Plantas/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Triticum/química , Cromatografia Líquida , Fermentação , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/metabolismo , Espectrometria de Massas em Tandem , Triticum/genética , Triticum/metabolismo , Triticum/microbiologia
12.
J Agric Food Chem ; 67(39): 10844-10852, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31525997

RESUMO

The discovery of 4-hydroxyphenylpyruvate dioxygenase (HPPD, EC 1.13.11.27) inhibitors has been an active area of research due to their great potential as herbicides for weed control. Starting from the binding mode of known inhibitors of HPPD, a series of HPPD inhibitors with new molecular scaffolds were designed and synthesized by hybridizing 2-benzoylethen-1-ol and isoindoline-1,3-dione fragments. The results of the in vitro tests indicated that the newly synthesized compounds showed good HPPD inhibitory activity with IC50 values against the recombinant Arabidopsis thaliana HPPD (AtHPPD) ranging from 0.0039 µM to over 1 µM. Most promisingly, compound 4ae, 2-benzyl-5-(5-hydroxy-1,3-dimethyl-1H-pyrazole-4- carbonyl)isoindoline-1,3-dione, showed the highest AtHPPD inhibitory activity with a Ki value of 3.92 nM, making it approximately 10 times more potent than pyrasulfotole (Ki = 44 nM) and slightly more potent than mesotrione (Ki = 4.56 nM). In addition, the cocrystal structure of the AtHPPD-4ae complex was successfully resolved at a resolution of 1.8 Å. The X-ray diffraction analysis indicated that the two carbonyl groups of 2-benzoylethen-1-ol formed a bidentate chelating interaction with the metal ion, while the isoindoline-1,3-dione moiety formed pronounced π-π stacking interactions with Phe381 and Phe424. Moreover, water-mediated hydrogen bonding interactions were observed between Asn282 and the nitrogen atoms of the pyrazole ring of 4ae. The above results showed that the pyrazole-isoindoline-1,3-dione hybrid is a promising scaffold for developing HPPD inhibitors.


Assuntos
4-Hidroxifenilpiruvato Dioxigenase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Herbicidas/farmacologia , Isoindóis/farmacologia , Proteínas de Plantas/antagonistas & inibidores , Pirazóis/farmacologia , 4-Hidroxifenilpiruvato Dioxigenase/química , 4-Hidroxifenilpiruvato Dioxigenase/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Herbicidas/síntese química , Herbicidas/química , Isoindóis/química , Cinética , Estrutura Molecular , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/crescimento & desenvolvimento , Pirazóis/química , Relação Estrutura-Atividade
13.
Plant Mol Biol ; 101(4-5): 455-469, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31541388

RESUMO

Regulation of abscisic acid (ABA) signaling is crucial in balancing responses to abiotic stresses and retaining growth in planta. An ABA receptor (PYL/RCAR) and a protein phosphatase (PP2C), a co-receptor, form a complex upon binding to ABA. Previously we reported that the second and fourth positions in the VxGΦL motif of PP2Cs from Oryza sativa are critical in the interaction of PP2Cs with PYL/RCARs. Considering substantial effects of the VxGΦL motif on ABA signaling outputs, further comprehensive characterization of residues in the second and fourth positions are required. Here we surveyed the second and fourth positions of the VxGΦL motif by combination of biochemical, structural and physiological analyses. We found that the fourth position of the VxGΦL motif, highly conserved to small hydrophobic residues, was a key determinant of the OsPP2C50:OsPYL/RCAR interactions across subfamilies. Large hydrophobic or any hydrophilic residues in the fourth position abrogated ABA responsiveness. Analysis of crystal structures of OsPP2C50 mutants, S265L/I267V ("LV"), I267L ("SL") and I267W ("SW"), in complex with ABA and OsPYL/RCAR3, along with energy calculation of the complexes, uncovered that a bulky hydrophobic residue in the fourth position of the VxGΦL motif pushed away side chains of nearby residues, conferring side-chain rotameric energy stress. Hydrophilic residues in this position imposed solvation energy stress to the PP2C:PYL/RCAR complex. Germination and gene expression analyses corroborated that OsPP2C50 AS and AK mutants modulated ABA responsiveness in Arabidopsis. Our results suggest that ABA responsiveness could be fine-tuned by the fourth position of the VxGΦL motif on PP2Cs. KEY MESSAGE: We comprehensively surveyed the VxGΦL motif to find that the fourth position, highly conserved to small hydrophobic residues, was critical in regulating ABA responsiveness.


Assuntos
Motivos de Aminoácidos , Oryza/fisiologia , Fosfoproteínas Fosfatases/química , Proteínas de Plantas/química , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Arabidopsis/genética , Clonagem Molecular , Cristalografia por Raios X , Oryza/genética , Oryza/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Plantas Geneticamente Modificadas/metabolismo , Transdução de Sinais
14.
J Agric Food Chem ; 67(40): 11198-11209, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31532988

RESUMO

The importance of inhibition sensitivity for xylanase functionality in bread making was investigated using mutants of the wild-type Bacillus subtilis xylanase (XBSTAXI), sensitive to Triticum aestivum xylanase inhibitor (TAXI). XBSNI, a mutant with reduced sensitivity to TAXI, and XBSTI, a mutant sensitive to all wheat endogenous proteinaceous inhibitors (TAXI, Xylanase Inhibiting Protein and Thaumatin-like Xylanase Inhibitor) were used. The higher inhibition sensitivity of XBSTAXI and XBSTI compared to XBSNI was associated with a respective 7- and 53-fold increase in enzyme dosage required for a maximal increase in bread loaf volume. XBSTI and XBSTAXI were only active during the mixing phase and the beginning of fermentation, while XBSNI was able to hydrolyze arabinoxylan until the end of fermentation. In spite of this difference in activity profile, no differences in loaf volume were observed for the different xylanases at optimal concentrations. Dough extensional viscosity analysis suggests that increased water availability as a result of xylanase activity favors starch-starch and starch-gluten interactions and drives the improvement in bread loaf volume.


Assuntos
Bacillus subtilis/enzimologia , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/química , Pão/análise , Endo-1,4-beta-Xilanases/antagonistas & inibidores , Endo-1,4-beta-Xilanases/química , Inibidores Enzimáticos/química , Proteínas de Plantas/química , Bacillus subtilis/química , Bacillus subtilis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/metabolismo , Inibidores Enzimáticos/metabolismo , Farinha/análise , Manipulação de Alimentos , Hidrólise , Mutação , Proteínas de Plantas/metabolismo , Triticum/química , Triticum/metabolismo , Viscosidade
15.
J Agric Food Chem ; 67(41): 11373-11379, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31539240

RESUMO

Cadmium bioremediation with metal-binding proteins is primarily conducted using metallothioneins (MTs). However, in the present study, we investigated a non-MT cadmium-binding protein from Lentinula edodes (LECBP) as a remediation tool for cadmium biosorption in Escherichia coli. The results indicated that the expression of LECBP significantly enhanced the cadmium biosorption capacity of transgenic E. coli. The secondary structure and conformation of LECBP were changed after binding with cadmium as evidenced by circular dichroism and fluorescence spectroscopy. The results of Fourier transform infrared spectroscopy indicated that carboxyl oxygen and amino nitrogen atoms were involved in the interaction between LECBP and cadmium. The results further demonstrated that glutamic acid and histidine residues are the potential binding sites. Our results have thus provided new insights into cadmium bioremediation in an aquatic environment.


Assuntos
Cádmio/metabolismo , Metalotioneína/metabolismo , Proteínas de Plantas/metabolismo , Cogumelos Shiitake/genética , Sítios de Ligação , Biodegradação Ambiental , Cádmio/química , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Metalotioneína/química , Metalotioneína/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Cogumelos Shiitake/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
16.
BMC Plant Biol ; 19(1): 347, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395025

RESUMO

BACKGROUND: Flavonoid 3'-hydroxlase (F3'H) is an important enzyme in determining the B-ring hydroxylation pattern of flavonoids. In monocots, previous studies indicated the presence of two groups of F3'Hs with different enzyme activities. One F3'H in rice was found to display novel chrysoeriol-specific 5'-hydroxylase activity. However, the evolutionary history of monocot F3'Hs and the molecular basis for the observed catalytic difference remained elusive. RESULTS: We performed genome-wide survey of 12 common monocot plants, and identified a total of 44 putative F3'H genes. The results showed that F3'H gene family had underwent volatile lineage-specific gene duplication and gene loss events in monocots. The expansion of F3'H gene family was mainly attributed to dispersed gene duplication. Phylogenetic analyses showed that monocot F3'Hs have evolved into two independent lineages (Class I and Class II) after gene duplication in the common ancestor of monocot plants. Evolutionary dynamics analyses had detected positive natural selection in Class II F3'Hs, acting on 7 specific amino acid sites. Protein modelling showed these selected sites were mainly located in the catalytic cavity of F3'H. Sequence alignment revealed that Class I and Class II F3'Hs displayed amino acid substitutions at two critical sites previously found to be responsible for F3'H and flavonoid 3'5'-hydroxylase (F3'5'H) activities. In addition, transcriptional divergence was also observed for Class I and Class II F3'Hs in four monocot species. CONCLUSIONS: We concluded that monocot F3'Hs have evolved into two independent lineages (Mono_F3'H Class I and Class II), after gene duplication during the common ancestor of monocot plants. The functional divergence of monocot F3'H Class II has been affected by positive natural selection, which acted on specific amino acid sites only. Critical amino acid sites have been identified to have high possibility to affect the substrate specificity of Class II F3'Hs. Our study provided an evolutionary and protein structural explanation to the previously observed chrysoeriol-specific 5'-hydroxylation activity for CYP75B4 in rice, which may also be true for other Class II F3'Hs in monocots. Our study presented clear evidence of plant-environmental interaction at the gene evolutionary level, and would guide future functional characterization of F3'Hs in cereal plants.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Grão Comestível/genética , Proteínas de Plantas/genética , Sistema Enzimático do Citocromo P-450/química , Grão Comestível/enzimologia , Evolução Molecular , Duplicação Gênica , Modelos Moleculares , Filogenia , Proteínas de Plantas/química , Seleção Genética , Alinhamento de Sequência
17.
J Agric Food Chem ; 67(33): 9241-9253, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31369258

RESUMO

Antiviral compounds targeting viral replicative processes have been studied as an alternative for the control of begomoviruses. Previously, we have reported that the peptide AmPep1 has strong affinity binding to the replication origin sequence of tomato yellow leaf curl virus (TYLCV). In this study, we describe the mechanism of action of this peptide as a novel alternative for control of plant-infecting DNA viruses. When AmPep1 was applied exogenously to tomato and Nicotiana benthamiana plants infected with TYLCV, a decrease in the synthesis of the two viral DNA strands (CS and VS) was observed, with a consequent delay in the development of disease progress in treated plants. The chemical mechanism of action of AmPep1 was deduced using Raman spectroscopy and molecular modeling showing the formation of chemical interactions such as H bonds and electrostatic interactions and the formation of π-π interactions between both biomolecules contributing to tampering with the viral replication.


Assuntos
Amaranthus/química , Antivirais/química , Antivirais/farmacologia , Begomovirus/efeitos dos fármacos , Peptídeos/química , Peptídeos/farmacologia , RNA Viral/química , Replicação Viral/efeitos dos fármacos , Begomovirus/química , Begomovirus/genética , Begomovirus/fisiologia , Sequências Repetidas Invertidas/efeitos dos fármacos , Lycopersicon esculentum/virologia , Doenças das Plantas/virologia , Proteínas de Plantas/química , RNA Viral/genética , Tabaco/virologia
18.
J Agric Food Chem ; 67(37): 10296-10305, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31464437

RESUMO

Grass pea is an orphan legume that is grown in many places in the world. It is a high-protein, drought-tolerant legume that is capable of surviving extreme environmental challenges and can be a sole food source during famine. However, grass pea produces the neurotoxin ß-N-oxalyl-L-α,ß-diaminopropionic acid (ß-ODAP), which can cause a neurological disease. This crop is promising as a food source for both animals and humans if ß-ODAP levels and other antinutritional factors such as protease inhibitors are lowered or removed. To understand more about these proteins, a proteomic analysis of grass pea was conducted using three different extraction methods to determine which was more efficient at isolating antinutritional factors. Seed proteins extracted with Tris-buffered saline (TBS), 30% ethanol, and 50% isopropanol were identified by mass spectrometry, resulting in the documentation of the most abundant proteins for each extraction method. Mass spectrometry spectral data and BLAST2GO analysis led to the identification of 1376 proteins from all extraction methods. The molecular function of the extracted proteins revealed distinctly different protein functional profiles. The majority of the TBS-extracted proteins were annotated with nutrient reservoir activity, while the isopropanol extraction yielded the highest percentage of endopeptidase proteinase inhibitors. Our results demonstrate that the 50% isopropanol extraction method was the most efficient at isolating antinutritional factors including protease inhibitors.


Assuntos
Fracionamento Químico/métodos , Fabaceae/química , Extratos Vegetais/isolamento & purificação , Inibidores de Proteases/isolamento & purificação , Sementes/química , Endopeptidases/química , Fabaceae/genética , Fabaceae/metabolismo , Espectrometria de Massas , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Proteômica , Sementes/genética , Sementes/metabolismo
19.
J Agric Food Chem ; 67(38): 10713-10725, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31453702

RESUMO

Converting peanut protein biomass waste into environmentally friendly meat substitutes by a high-moisture extrusion process can help solve both resource and waste problems and be "double green". A multiscale method combined with some emerging techniques such as atomic force microscopy-based infrared spectroscopy and X-ray microscopy was used to make the whole extrusion process visible to show the process of forming a meat-like fibrous structure using two-dimensional and three-dimensional perspectives. The results showed that the protein molecules underwent dramatic structural changes and unfolded in the extruder barrel, which created favorable conditions for molecular rearrangement in the subsequent zones. It was confirmed that the meat-like fibrous structure started to form at the junction of the die and the cooling zone and that this structure was caused by the phase separation and rearrangement of protein molecules in the cooling zone. Moreover, the interactions between hydrogen bonds and disulfide bonds formed in the cooling zone maintained the meat-like fibrous structure with an α-helix > ß-sheet > ß-turn > random coil. Of the two main peanut proteins, arachin played a greater role in forming the fibrous structure than conarachin, especially those subunits of arachin with a molecular weight of 42, 39, and 22 kDa.


Assuntos
Arachis/química , Aromatizantes/química , Extratos Vegetais/química , Proteínas de Plantas/química , Resíduos/análise , Aromatizantes/isolamento & purificação , Química Verde , Ligações de Hidrogênio , Raios Infravermelhos , Extratos Vegetais/isolamento & purificação , Conformação Proteica
20.
Ultrason Sonochem ; 59: 104728, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31421619

RESUMO

Ultra-sonication (US) at varying intensities (200 W, 300 W and 400 W) and hydrodynamic cavitation (HC) at increasing pressures (6 bar, 8 bar and 10 bar) on freshly extracted peanut milk as non-thermal processing of milk for enhanced quality. The effects of US and HC was investigated on physico-chemical properties of peanut milk, microbial inactivation (total plate count and yeasts and molds), microstructure by optical microscopy and particle size, ζ-potential, sedimentation index, rheology and color measurements. The high temperature short time (HTST) treated milk samples have shown 1.53 and 2 log reduction in TPC, yeast and molds respectively with highest protein hydrolysis of 15.7%. Among the non-thermal treatments HC has shown highest log reduction of TPC at around 1.2 for sample treated at 10 bar pressure, whereas the US treatment was most effective for yeast and mold at 400 W with log reduction of 0.9. A non-Newtonian flow behaviour was observed for all peanut milk samples. Viscosity determined by Herschel-Bulkley equation decreased significantly (p > 0.05) after both cavitation treatments. The US was found to be superior to HC and HTST with improved separation index and colour attributes. Therefore, the US and HC appear to be a remarkable non-thermal processing methods for peanut milk and or any dairy or non-dairy beverages.


Assuntos
Arachis/química , Bebidas/microbiologia , Fenômenos Químicos , Hidrodinâmica , Viabilidade Microbiana , Sonicação , Arachis/microbiologia , Cor , Concentração de Íons de Hidrogênio , Hidrólise , Fenômenos Ópticos , Tamanho da Partícula , Proteínas de Plantas/química , Solubilidade , Temperatura Ambiente
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