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1.
J Agric Food Chem ; 67(45): 12590-12598, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31639305

RESUMO

Carotenoids play key roles in photosynthesis and photoprotection. Few multicellular plants produce the ketocarotenoid astaxanthin, a strong antioxidant; however, Arabidopsis thaliana lines overexpressing the Chlamydomonas reinhardtii ß-carotene ketolase (CrBKT) accumulated high amounts of astaxanthin in the leaves. In this study, we investigated the changed regulation of key metabolic pathways and the tolerance of the engineered plants to biotic and abiotic stresses resulting from the heterologous expression of CrBKT. Transcriptome analysis identified 1633 and 1722 genes that were differentially expressed in the leaves and siliques, respectively, of CrBKT-overexpressing plants (line CR5) as compared to wild-type Arabidopsis. These genes were enriched in the carotenoid biosynthetic pathways, and plant hormone biosynthesis and signaling pathways. In particular, metabolic profiling showed that, as compared to the wild-type leaves and siliques, overexpression of CrBKT increased the levels of most amino acids, but decreased the contents of sugars and carbohydrates. Furthermore, CR5 plants had lower sensitivity to abscisic acid (ABA) and increased tolerance to oxidative stress. CR5 plants also exhibited enhanced resistance to the bacterial pathogen Pseudomonas syringae pv. tomato DC3000. Our study provides insight into the regulation of carotenoids and the related pathways, which may be involved in plant response to oxidative stress and pathogen infection.


Assuntos
Arabidopsis/genética , Arabidopsis/metabolismo , Doenças das Plantas/microbiologia , Plantas Geneticamente Modificadas/metabolismo , Ácido Abscísico/metabolismo , Arabidopsis/química , Arabidopsis/microbiologia , Regulação da Expressão Gênica de Plantas , Estresse Oxidativo , Doenças das Plantas/genética , Reguladores de Crescimento de Planta/metabolismo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/microbiologia , Pseudomonas syringae/fisiologia , Xantofilas/biossíntese
2.
J Agric Food Chem ; 67(35): 9877-9884, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31398030

RESUMO

Heavy metal contaminants and nutrient deficiencies in soil negatively affect crop growth and human health. The plant cadmium resistance (PCR) protein transports heavy metals. The abundance of PCR is correlated with that of cell number regulator (CNR) protein, and the two proteins have similar conserved domains. Hence, CNR might also participate in heavy metal transport. We isolated and analyzed TaCNR5 from wheat (Triticum aestivum). The expression level of TaCNR5 in the shoots of wheat increased under cadmium (Cd), zinc (Zn), or manganese (Mn) treatments. Transgenic plants expressing TaCNR5 showed enhanced tolerance to Zn and Mn. Overexpression of TaCNR5 in Arabidopsis increased Cd, Zn, and Mn translocation from roots to shoots. The concentrations of Zn and Mn in rice grains were increased in transgenic plants expressing TaCNR5. These roles of TaCNR5 in the translocation and distribution of heavy metals mean that it has potential as a genetic biofortification tool to fortify cereal grains with micronutrients.


Assuntos
Manganês/metabolismo , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Triticum/genética , Zinco/metabolismo , Arabidopsis/química , Arabidopsis/genética , Arabidopsis/metabolismo , Biofortificação , Transporte Biológico , Cádmio/análise , Cádmio/metabolismo , Manganês/análise , Oryza/química , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Triticum/química , Triticum/metabolismo , Zinco/análise
3.
J Sci Food Agric ; 99(15): 6903-6910, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31415094

RESUMO

BACKGROUND: Bacillus thuringiensis (Bt) synthesizes Cry1Ac protein, which is toxic to many lepidopteran pests, and the cry1ac gene has been expressed in several transgenic crop plants. The Cry1Ac protein has been isolated from Bt kurstaki HD73 and purified to homogeneity. Polyclonal antibodies were raised against purified Cry1Ac in rabbits and goat. Sandwich ELISA was developed for Cry1Ac using goat IgG as a coating antibody, and affinity-purified rabbit IgG as the primary antibody. RESULTS: The sensitivity of the assay was in the range of 0.47-1000 ng. It was subsequently employed in validating biological samples. Fifteen different cotton-seed samples were screened: 12 were found to be Bt positive and 3 Bt negative. The CS7 seeds showed the highest Bt content of 8.51 ± 0.45 µg g-1 , followed by CS8 (6.0 ± 0.02 µg g-1 ), CS15 (5.9 ± 0.03 µg g-1 ), CS9 (5.5 ± 0.05 µg g-1 ), and CS10 (4.83 ± 0.013 µg g-1 ). The CS5 seeds showed Bt content of 3.6 ± 0.21 µg g-1 . The F2 generation, CS6 (Kaveri seeds) showed lower Bt content (2.9 ± 0.06 µg g-1 ). The CL5 samples showed Cry1Ac content of 0.99 ± 0.009 µg g-1 . The amount of Cry1Ac protein in leaves, stem, and roots of germinated Bt cotton plants (CS10 and CS4) were 1.76 ± 0.15 µg g-1 , 1.9 ± 0.01 µg g-1 , 2.0 ± 0.1 µg g-1 , and 1.6 ± 0.15 µg g-1 , 1.9 ± 0.01 µg g-1 , and 2.0 ± 0.01 µg g-1 dry tissue, respectively. CONCLUSION: The method developed can be used for screening the expression levels of Cry1Ac in different transgenic Bt cultivars and also spurious Bt cotton seeds procured by farmers. © 2019 Society of Chemical Industry.


Assuntos
Bacillus/química , Endotoxinas/análise , Ensaio de Imunoadsorção Enzimática/métodos , Gossypium/química , Plantas Geneticamente Modificadas/química , Animais , Anticorpos/análise , Anticorpos/imunologia , Bacillus/metabolismo , Endotoxinas/imunologia , Endotoxinas/metabolismo , Gossypium/genética , Gossypium/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Coelhos , Sementes/química , Sementes/genética , Sementes/metabolismo
4.
J Agric Food Chem ; 67(31): 8559-8572, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31298518

RESUMO

Avenin-like b protein is rich in cysteine residues, providing the possibility to form intermolecular disulfide bonds and then participate in glutenin polymerization. Site-directed mutagenesis was adopted to produce mutant avenin-like b gene encoding mutant avenin-like b protein, in which one tyrosine codon at the C-terminal is substituted by a cysteine codon. Compared with the control lines, both transgenic lines with wild-type and mutant avenin-like b genes demonstrated superior dough properties. While compared within the transgenic lines, the mutant lines showed relative weaker dough strength and decreased sodium-dodecyl-sulfate sedimentation volumes (from 69.7 mL in line WT alb-1 to 41.0 mL in line Mut alb-4). These inferior dough properties were accompanied by the lower contents of large-sized glutenin polymers, the decreased particle diameters of glutenin macropolymer (GMP), due to the lower content of intermolecular ß-sheets (from 39.48% for line WT alb-2 to 30.21% for line Mut alb-3) and the varied contents of disulfide bonds (from 137.37 µmol/g for line WT alb-1 to 105.49 µmol/g for line Mut alb-4) in wheat dough. The extra cysteine might alter the original disulfide bond structure, allowing cysteine residue usually involved in an intermolecular disulfide bond to become available for an intrachain disulfide bond. Avenin-like b proteins were detected in glutenin macropolymers, providing further evidence for this protein to participate in the polymerization of glutenin. This is the first time to investigate the effect of a specific cysteine residue in the avenin-like b protein on flour quality.


Assuntos
Cisteína/genética , Farinha/análise , Plantas Geneticamente Modificadas/genética , Prolaminas/genética , Triticum/genética , Pão/análise , Cisteína/metabolismo , Dissulfetos/química , Manipulação de Alimentos , Mutagênese Sítio-Dirigida , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/metabolismo , Prolaminas/metabolismo , Triticum/química , Triticum/metabolismo
5.
J Agric Food Chem ; 67(28): 7986-7994, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31282158

RESUMO

Compositional analyses were performed on samples of rice grain, straw, and derived bran obtained from golden rice event GR2E and near-isogenic control PSBRc82 rice grown at four locations in the Philippines during 2015 and 2016. Grain samples were analyzed for key nutritional components, including proximates, fiber, polysaccharides, fatty acids, amino acids, minerals, vitamins, and antinutrients. Samples of straw and bran were analyzed for proximates and minerals. The only biologically meaningful difference between GR2E and control rice was in levels of ß-carotene and other provitamin A carotenoids in the grain. Except for ß-carotene and related carotenoids, the compositional parameters of GR2E rice were within the range of natural variability of those components in conventional rice varieties with a history of safe consumption. Mean provitamin A concentrations in milled rice of GR2E can contribute up to 89-113% and 57-99% of the estimated average requirement for vitamin A for preschool children in Bangladesh and the Philippines, respectively.


Assuntos
Oryza/genética , Plantas Geneticamente Modificadas/química , Sementes/química , Aminoácidos/análise , Aminoácidos/metabolismo , Bangladesh , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Alimentos Geneticamente Modificados , Engenharia Genética , Valor Nutritivo , Oryza/química , Oryza/metabolismo , Filipinas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Provitaminas/análise , Provitaminas/metabolismo , Sementes/genética , Sementes/metabolismo , Vitamina A/análise , Vitamina A/metabolismo , beta Caroteno/análise , beta Caroteno/metabolismo
6.
J Agric Food Chem ; 67(28): 7898-7907, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31282664

RESUMO

This study aimed to explore the effects of silencing HB12 and TT8 genes on protein utilization characteristics of alfalfa. Ground samples of 11 HB12-silenced (HB12i), 5 TT8-silenced (TT8i) and 4 wild type (WT) were incubated in a Daisy II incubator with N15 labeled ammonium sulfate for 0, 4, 8, 12, and 24 h. CP degradation and degradational kinetics, microbial nitrogen fractions, and protein metabolic profiles were determined. Moreover, relationships between protein profiles and FTIR spectral parameters were estimated. Results showed that transgenic alfalfa had lower CP degradation, microbial protein, and total available protein compared with WT, especially for HB12i. In addition, CP degradation and protein metabolic profiles were closely correlated with FTIR spectral parameters and thereby could be predicted from spectral parameters. In conclusion, silencing of HB12 and TT8 genes in alfalfa decreased protein degradational and metabolic profiles, which were predictable with FTIR spectral parameters.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Inativação Gênica , Proteínas de Homeodomínio/genética , Medicago sativa/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Rúmen/metabolismo , Ração Animal/análise , Animais , Bactérias/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Bovinos , Digestão , Proteínas de Homeodomínio/metabolismo , Cinética , Medicago sativa/química , Medicago sativa/metabolismo , Proteínas de Plantas/química , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Proteólise , Rúmen/química , Rúmen/microbiologia
7.
J Agric Food Chem ; 67(26): 7466-7474, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31184886

RESUMO

The ZMM28 protein encoded by the zmm28 gene is endogenous to maize. DP202216 maize was genetically modified to increase and extend expression of the zmm28 gene relative to native zmm28 gene expression, resulting in plants with enhanced grain yield potential. Evaluation of the history of safe use (HOSU) is one component of the safety assessment framework for a newly expressed protein in a GM crop. The deduced amino acid sequence of the introduced ZMM28 protein in DP202216 maize is identical to the ZMM28 protein in nonmodified conventional maize. The ZMM28 protein has also been found in selected varieties of sweet corn kernels, and closely related proteins are found in other commonly consumed food crops. Concentrations of the ZMM28 protein in event DP202216 maize, conventional maize, and sweet corn are reported. This information supports, in part, the evaluation of HOSU, which can be leveraged in the safety assessment of the ZMM28 protein. Additional studies will be considered in the food and feed safety assessment of the DP202216 maize event.


Assuntos
Proteínas de Plantas/química , Plantas Geneticamente Modificadas/química , Zea mays/química , Sequência de Aminoácidos , Qualidade de Produtos para o Consumidor , Inocuidade dos Alimentos , Alimentos Geneticamente Modificados , Humanos , Dados de Sequência Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Alinhamento de Sequência , Zea mays/genética , Zea mays/metabolismo
8.
BMC Plant Biol ; 19(1): 208, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31109298

RESUMO

BACKGROUND: Cotton fiber is a single cell that arises from the epidermis of ovule. It is not only a main economic product of cotton, but an ideal material for studying on the growth and development of plant cell. Our previous study indicated that phytosterol content and the ratio of campesterol to sitosterol fluctuated regularly in cotton fiber development. However, what effects of modified phytosterol content and composition on the growth and development of cotton fiber cell is unknown. In this study, we overexpressed the GhSMT2-1, a cotton homologue of sterol C-24 methyltransferase 2 gene in transgenic upland cotton plants to modify phytosterol content and composition in fiber cells and investigated the changes on fiber elongation and secondary cell wall deposition. RESULTS: GhSMT2-1 overexpression led to changes of phytosterol content and the ratio of campesterol to sitosterol in fiber cell. At the rapid elongation stage of fiber cell, total phytosterol and sitosterol contents were increased while campesterol content was decreased in transgenic fibers when compared to control fibers. Accordingly, the ratio of campesterol to sitosterol declined strikingly. Simultaneously, the transgenic fibers were shorter and thicker than control fibers. Exogenous application of sitosterol or campesterol separately inhibited control fiber cell elongation in cotton ovule culture system in vitro. In addition, campesterol treatment partially rescued transgenic fiber elongation. CONCLUSION: These results elucidated that modification of phytosterol content and composition influenced fiber cell elongation and secondary cell wall formation. High sitosterol or low ratio of campesterol to sitosterol suppresses fiber elongation and/or promote secondary cell wall deposition. The roles of sitosterol and campesterol were discussed in fiber cell development. There might be a specific ratio of campesterol to sitosterol in different developmental stage of cotton fibers, in which GhSMT2-1 play an important role. Our study, at a certain degree, provides novel insights into the regulatory mechanisms of fiber cell development.


Assuntos
Gossypium/química , Gossypium/fisiologia , Fitosteróis/química , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Crescimento Celular , Parede Celular , Fibra de Algodão , Gossypium/genética , Metiltransferases/genética , Metiltransferases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia
9.
J Agric Food Chem ; 67(17): 4947-4957, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30994343

RESUMO

Accumulating pesticide (and herbicide) residues in soils have become a serious environmental problem. This study focused on identifying the removal of two widely used pesticides, isoproturon (IPU) and acetochlor (ACT), by a genetically developed paddy (or rice) plant overexpressing an uncharacterized glycosyltransferase (IRGT1). IRGT1 conferred plant resistance to isoproturon-acetochlor, which was manifested by attenuated cellular injury and alleviated toxicity of rice under isoproturon-acetochlor stress. A short-term study showed that IRGT1-transformed lines removed 33.3-48.3% of isoproturon and 39.8-53.5% of acetochlor from the growth medium, with only 59.5-72.1 and 58.9-70.4% of the isoproturon and acetochlor remaining in the plants compared with the levels in untransformed rice. This phenotype was confirmed by IRGT1-expression in yeast ( Pichia pastoris) which grew better and contained less isoproturon-acetochlor than the control cells. A long-term study showed that isoproturon-acetochlor concentrations at all developmental stages were significantly lower in the transformed rice, which contain only 59.3-69.2% (isoproturon) and 51.7-57.4% (acetochlor) of the levels in wild type. In contrast, UPLC-Q-TOF-MS/MS analysis revealed that more isoproturon-acetochlor metabolites were detected in the transformed rice. Sixteen metabolites of isoproturon and 19 metabolites of acetochlor were characterized in rice for Phase I reactions, and 9 isoproturon and 13 acetochlor conjugates were characterized for Phase II reactions in rice; of these, 7 isoproturon and 6 acetochlor metabolites and conjugates were reported in plants for the first time.


Assuntos
Herbicidas/metabolismo , Oryza/genética , Oryza/metabolismo , Resíduos de Praguicidas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Engenharia Genética , Herbicidas/análise , Oryza/química , Resíduos de Praguicidas/química , Compostos de Fenilureia/análise , Compostos de Fenilureia/metabolismo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Poluentes do Solo/química , Espectrometria de Massas em Tandem , Toluidinas/análise , Toluidinas/metabolismo
10.
J Agric Food Chem ; 67(17): 4793-4799, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31002246

RESUMO

The utilization of the nutrient potential of alfalfa ( Medicago sativa L.) cannot be maximized because of its rapidly degradable protein content in the rumen, leading to waste and various digestive disorders. This might be alleviated if protein-binding proanthocyanidins are present in aerial parts of alfalfa forage in adequate amounts. The Lc (bHLH) and C1 (MYB) genes of maize are transcription factors known to be collectively involved in the regulation of anthocyanin biosynthetic pathways. The objective of this study was to investigate the effect of Lc and C1 gene transformations on the proanthocyanidin content, nutrient composition, and degradation characteristics of proteins and carbohydrates by comparing the transgenic alfalfa with its parental nontransgenic (NT) alfalfa and commercial AC-Grazeland cultivar. The DNA extracted from transgenic plants was tested for the presence of respective transgenes by amplification with specific primers of respective transgenes using PCR. Both Lc-single and LcC1-double transgenic alfalfa accumulated both monomeric and polymeric proanthocyanidins with total proanthocyanidins ranging from ca. 460 to 770 µg/g of DM. The C1-transgenic alfalfa did not accumulate proanthocyanidins similar to NT alfalfa. The C1 gene increased the NPN content significantly only in C1-single and Lc1C1-double transgenic alfalfa. The LcC1 combination seemed to have a synergic effect on reducing sugar in alfalfa. In contrast, the Lc gene appears to have a negative effect on starch content. The C1 gene tended to lower the PB3 content irrespective of the presence of the Lc gene. Although the cotransformation of Lc and C1 increased the total N/CHO ratio compared to Lc single gene transformation, the total N/CHO ratio of transgenic alfalfa was not significantly different from NT. In conclusion, Lc-bHLH single and LcC1 double gene transformation resulted in the accumulation of proanthocyanidins and affected the chemical profiles in alfalfa, which altered ruminal degradation patterns and impacted the nutrient availability of alfalfa in ruminant livestock systems.


Assuntos
Flavonoides/metabolismo , Medicago sativa/genética , Medicago sativa/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/metabolismo , Proantocianidinas/metabolismo , Fatores de Transcrição/genética , Ração Animal/análise , Animais , Bovinos , Medicago sativa/química , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Rúmen/metabolismo , Fatores de Transcrição/metabolismo , Zea mays/genética
11.
Molecules ; 24(8)2019 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-31013652

RESUMO

A considerable amount of bioactive compounds have been used for the biopharmaceutical engineering to help human health and nutrition. Hairy root culture (HRC) or transgenic root is a favourable alternative technique for phytochemical production. Ligularia fischeri is a significant source of pharmaceutically important active compounds with an enormous range of health care applications. HRC of L. fischeri was developed using Agrobacterium rhizogenes for the production of polyphenolic compounds with antioxidant, antimicrobial, antidiabetic, anticancer and anti-inflammatory pharmaceutical activities. Hairy roots (HRs) were selected by morphological assessment, genetic and molecular analyses. The maximum accumulation of fresh mass (94.15 g/L) and dry mass (9.45 g/L) was recorded in MS liquid medium supplemented with 30 g/L sucrose at 28 days. Furthermore, HRs successfully produced numerous polyphenolic compounds, including six hydroxycinnamic acids, seven flavonols, seven hydroxybenzoic acids, vanillin, resveratrol, pyrogallol, homogentisic, and veratric acids, which were identified by UHPLC analysis. HRs produced higher total phenolic (185.65 mg/g), and flavonoid (5.25 mg/g) contents than non-transformed roots (125.55 mg/g and 3.75 mg/g). As a result of these metabolic changes, pharmaceutical activities were found higher in HRs than non-transformed roots (NTRs). The present study indicates that HRC has the potential to increase the content of beneficial polyphenolic compounds with higher potential pharmaceutical activities. To the best of our knowledge, the present study is the first report on enhancing the production of polyphenolic compounds with pharmaceutical activities from the HRCs of L. fischeri.


Assuntos
Asteraceae , Flavonoides , Fenóis/farmacologia , Raízes de Plantas , Asteraceae/química , Asteraceae/genética , Asteraceae/metabolismo , Avaliação Pré-Clínica de Medicamentos , Flavonoides/biossíntese , Flavonoides/química , Flavonoides/farmacologia , Humanos , Células MCF-7 , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
12.
Food Chem Toxicol ; 126: 313-321, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30831153

RESUMO

Examining tissue-specific expression and the measurement of protein abundance are important steps when assessing the performance of genetically engineered crops. Liquid chromatography-mass spectrometry offers many advantages over traditional methods for protein quantitation, especially when dealing with transmembrane proteins that are often difficult to express or generate antibodies against. In this study, discovery proteomics was used to detect the seven transgenic membrane-bound enzymes from the docosahexaenoic acid (DHA) biosynthetic pathway that had been engineered into canola. Subsequently, a targeted LC-MS/MS method for absolute quantitation was developed and applied to the simultaneous measurement of the seven DHA biosynthetic pathway enzymes in genetically modified canola grown across three sites. The results of this study demonstrated that the enzymatic proteins that drive the production of DHA using seed-specific promoters were detected only in mature and developing seed of DHA canola. None of the DHA biosynthesis pathway proteins were detected in wild-type canola planted in the same site or in the non-seed tissues of the transgenic canola, irrespective of the sampling time or the tissues tested. This study describes a streamlined approach to simultaneously measure multiple membrane-bound proteins in planta.


Assuntos
Brassica rapa/enzimologia , Ácidos Docosa-Hexaenoicos/biossíntese , Espectrometria de Massas/métodos , Proteínas de Membrana/química , Proteínas de Plantas/química , Plantas Geneticamente Modificadas/enzimologia , Brassica rapa/química , Brassica rapa/genética , Brassica rapa/metabolismo , Engenharia Genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Sementes/química , Sementes/enzimologia , Sementes/genética , Sementes/metabolismo
13.
J Agric Food Chem ; 67(14): 4080-4088, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30896940

RESUMO

The European Food Safety Authority (EFSA) oversees the safety assessment of genetically engineered (GE) crops in the European Union and has developed a study design and statistical approach for assessing the compositional equivalency between a GE crop and the corresponding non-GE crop on the basis of the results from a small number of concurrently grown reference lines. Confidence limits around the differences in mean analyte composition between the GE variety and the reference lines are compared with equivalence limits on the basis of the variability of the reference lines. Here, we evaluated the performance and consistency of the equivalence conclusions using a non-GE variety that is, by definition, equivalent to the non-GE crop. Using this approach across the same analytes with the same non-GE variety, it was found that equivalence could not be concluded for 19.7, 22.9, 25.4, and 53.5% of the analytes in four separate studies. In addition, equivalency conclusions for the same analyte often differed from study to study. These results call into question the consistency and value of this approach in the risk assessment of GE crops.


Assuntos
Produtos Agrícolas/química , Alimentos Geneticamente Modificados/normas , Plantas Geneticamente Modificadas/química , Produtos Agrícolas/genética , União Europeia/organização & administração , Inocuidade dos Alimentos , Engenharia Genética , Humanos , Plantas Geneticamente Modificadas/genética
14.
PLoS One ; 14(3): e0212840, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30835761

RESUMO

Increased concentrations of atmospheric CO2 are predicted to reduce the content of essential elements such as protein, zinc, and iron in C3 grains and legumes, threatening the nutrition of billions of people in the next 50 years. However, this prediction has mostly been limited to grain crops, and moreover, we have little information about either the underlying mechanism or an effective intervention to mitigate these reductions. Here, we present a broader picture of the reductions in elemental content among crops grown under elevated CO2 concentration. By using a new approach, flow analysis of elements, we show that lower absorption and/or translocation to grains is a key factor underlying such elemental changes. On the basis of these findings, we propose two effective interventions-namely, growing C4 instead of C3 crops, and genetic improvements-to minimize the elemental changes in crops, and thereby avoid an impairment of human nutrition under conditions of elevated CO2.


Assuntos
Atmosfera/química , Dióxido de Carbono/fisiologia , Produção Agrícola/métodos , Produtos Agrícolas/fisiologia , Fotossíntese/fisiologia , Produção Agrícola/tendências , Produtos Agrícolas/química , Fabaceae/química , Fabaceae/fisiologia , Comportamento Alimentar/fisiologia , Abastecimento de Alimentos , Humanos , Micronutrientes/administração & dosagem , Micronutrientes/fisiologia , Oryza/química , Oryza/fisiologia , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/fisiologia
15.
Mycotoxin Res ; 35(2): 169-176, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30706435

RESUMO

The aim of this study was to compare the fate of fumonisins in transgenic and non-transgenic corn during industrial dry milling. For this purpose, whole corn samples and their fractions (germ, pericarp, endosperm, corn meal, and grits) were collected from one of the major Brazilian milling plants, totaling 480 samples. There was no significant difference (p > 0.05) between mean fumonisin (FB1 + FB2) levels in transgenic (1130 µg/kg) and non-transgenic (920 µg/kg) whole corn. However, in non-transgenic germ, endosperm and corn meal fraction fumonisin levels were higher (2940 µg/kg, 250 µg/kg and 190 µg/kg, respectively) than in transgenic fractions (2180 µg/kg, 130 µg/kg and 85.0 µg/kg, respectively). Furthermore, the highest percentages of fumonisins were distributed in the germ, corresponding to about 87 and 76% of the total fumonisins present in the whole corn from non-transgenic and transgenic hybrids, respectively. Concerning the endosperm from non-transgenic and transgenic corn, approximately, 23% and 13% of the total fumonisins were retained after the dry milling. Further processing in corn meal (300 to 420 µm particle size) and grits (590 to 1190 µm) decreased the percentages of remaining fumonisins to 4% and 2% (transgenic) and 10% and 3% (non-transgenic corn), respectively. These results suggested that fumonisin concentration was higher in outer and inner non-transgenic fractions when compared to transgenic ones and that the fate of fumonisins during the industrial dry milling could be affected by the transgenic status. However, it was not possible to conclude that the difference was exclusively due to this variable.


Assuntos
Contaminação de Alimentos/análise , Fumonisinas/análise , Plantas Geneticamente Modificadas/química , Venenos/análise , Zea mays/química , Brasil , Indústria Alimentícia
16.
Biosens Bioelectron ; 129: 7-14, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30682690

RESUMO

A novel amperometric genosensor based on PNA probes covalently bound on the surface of Single Walled Carbon Nanotubes - Screen Printed Electrodes (SWCNT-SPEs) was developed and validated in samples of non-amplified genomic DNA extracted from genetically modified (GM)-Soy. The sandwich assay is based on a first recognition of a 20-mer portion of the target DNA by a complementary PNA Capture Probe (CP) and a second hybridization with a PNA Signalling Probe (SP), with a complementary sequence to a different portion of the target DNA. The SP was labelled with biotin to measure current signal by means of a final incubation of an Alkaline Phosphatase-streptavidin conjugate (ALP-Strp). The electrochemical detection was carried out using hydroquinone diphosphate (HQDP) as enzymatic substrate. The genoassay provided a linear range from 250 pM to 2.5 nM, LOD of 64 pM and LOQ of 215 pM Excellent selectivity towards one base mismatch (1-MM) or scrambled (SCR) sequences was obtained. A simple protocol for extraction and analysis of non-amplified soybean genomic DNA without sample treatment was developed and validated. Our study provides insight into how the outstanding recognition efficiency of PNAs can be combined with the unique properties of CNTs in terms of signal response enhancement for direct detection of genomic DNA samples at the level of interest without previous amplification.


Assuntos
Técnicas Biossensoriais/métodos , DNA de Plantas/análise , Nanotubos de Carbono/química , Sondas de Ácido Nucleico/química , Ácidos Nucleicos Peptídicos/química , Plantas Geneticamente Modificadas/genética , Soja/genética , DNA de Plantas/genética , Técnicas Eletroquímicas/métodos , Eletrodos , Limite de Detecção , Hibridização de Ácido Nucleico , Sondas de Ácido Nucleico/genética , Ácidos Nucleicos Peptídicos/genética , Plantas Geneticamente Modificadas/química , Soja/química
17.
Pest Manag Sci ; 75(8): 2124-2132, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30632285

RESUMO

BACKGROUND: The fall armyworm, Spodoptera frugiperda (J.E. Smith), is the first target pest that has developed resistance to Bt crops across several countries. Leaf tissue and whole plant assays were employed to determine the survival, development, progeny production, and net reproductive rate of all nine possible genotypes of Cry1A.105/Cry2Ab2-dual gene resistant S. frugiperda on non-Bt and MON 89034 maize expressing the Cry1A.105/Cry2Ab2 proteins. RESULTS: The homozygous resistant genotype was highly resistant to Bt plants. Genotypes possessing only Cry2Ab2 resistance alleles (RAs) or two Cry1A.105 RAs only were susceptible to MON 89034 with a functional dominance level (DML ) of 0.0-0.07 on MON 89034 plants. In contrast, genotypes containing two Cry1A.105 plus one Cry2Ab2 RA performed well on Bt plants, with a DML of 0.11-0.78. Significant numbers of survivors on Bt plants were also observed for genotypes containing a single Cry1A.105 RA, or a Cry1A.105 plus one or two Cry2Ab2 RAs, with a DML of 0.0-0.47. CONCLUSIONS: The fitness of individual resistant genes on pyramided Bt plants varied in the dual-gene resistance system. Genotypes containing more Cry1A.105 RAs performed better than those possessing more Cry2Ab2 RAs. The functional dominance level of an individual resistant gene in this system is related to the DML level in its corresponding single-gene system. Data generated from this study should fill gaps in understanding dual-/multiple-gene Bt resistance, as well as providing useful information for refining resistance modeling, improving resistance risk assessment, and developing management strategies for the sustainable use of pyramided Bt maize technology. © 2019 Society of Chemical Industry.


Assuntos
Proteínas de Bactérias/farmacologia , Endotoxinas/farmacologia , Proteínas Hemolisinas/farmacologia , Resistência a Inseticidas , Spodoptera/efeitos dos fármacos , Animais , Genótipo , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/fisiologia , Fenótipo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Spodoptera/crescimento & desenvolvimento , Spodoptera/fisiologia , Zea mays/química , Zea mays/crescimento & desenvolvimento
18.
J Sci Food Agric ; 99(1): 8-12, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29952140

RESUMO

The European Commission's assessment and approval process for genetically modified (GM) crops has resulted in only two GM crop varieties being licensed for cultivation in the European Union, one of which has been withdrawn. Unable to define GM crops satisfactorily, the European Commission has fallen back on a definition based on process. The shortcomings of this approach are all too clear as the Commission grapples with the advent of genome editing. This has led to a long and damaging delay in the Commission issuing an opinion on how genome-edited crops should be regulated. At the same time, national bans imposed by member states on GM crops without any evidence of safety concerns have been legalized. The Commission also faces the prospect of assessing an increasing number of GM and genome-edited crops with deliberately altered composition. In this article, the operation of regulations covering GM crops in the European Union and the effect they have had on the development of plant biotechnology are reviewed, while the issues raised by new technologies are discussed. It is argued that there is an urgent need for the European Union to shift its position on plant biotechnology if agriculture is to meet the challenges of coming decades. © 2018 The Author. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Produção Agrícola/legislação & jurisprudência , Produtos Agrícolas/genética , Plantas Geneticamente Modificadas/genética , Produção Agrícola/organização & administração , Produtos Agrícolas/química , Europa (Continente) , União Europeia , Inocuidade dos Alimentos , Alimentos Geneticamente Modificados , Genoma de Planta , Humanos , Plantas Geneticamente Modificadas/química
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 206: 165-169, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30099314

RESUMO

Discrimination of transgenic edible oil has become the focus of attention in the field of food safety. In this paper, we propose a method for discrimination of transgenic edible oils by using terahertz spectroscopy combine with weighted linear discriminant analysis (WLDA). To evaluate the lustiness of the model, we employ successive projection arithmetic (SPA) and partial least squares (PLS) to verify the discrimination performance through variable selection. The results demonstrate that the SPA-WLDA model has higher classification accuracy than PLS-WLDA. In conclusion, terahertz spectroscopy is coupled with chemometrics is an effective method for discriminating various types of transgenic edible oils.


Assuntos
Camellia/química , Óleos Vegetais/análise , Plantas Geneticamente Modificadas/química , Espectroscopia Terahertz/métodos , Análise Discriminante , Análise dos Mínimos Quadrados , Óleos Vegetais/química
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 206: 177-184, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30099316

RESUMO

Lignocellulosic biomass represents the only renewable carbon resource which is available in sufficient amounts to be considered as an alternative for our fossil-based carbon economy. However, an efficient biochemical conversion of lignocellulosic feedstocks is hindered by the natural recalcitrance of the biomass as a result of a dense network of cellulose, hemicelluloses, and lignin. These polymeric interconnections make a pretreatment of the biomass necessary in order to enhance the susceptibility of the polysaccharides. Here, we report on a detailed analysis of the favourable influence of genetic engineering for two common delignification protocols for lignocellulosic biomass, namely acidic bleaching and soda pulping, on the example of CAD deficient poplar. The altered lignin structure of the transgenic poplar results in a significantly accelerated and more complete lignin removal at lower temperatures and shorter reaction times compared to wildtype poplar. To monitor the induced chemical and structural alterations at the tissue level, confocal Raman spectroscopy imaging, FT-IR spectroscopy, and X-ray diffraction were used.


Assuntos
Oxirredutases do Álcool/deficiência , Lignina/química , Plantas Geneticamente Modificadas/química , Populus/química , Análise Espectral Raman/métodos , Biomassa , Lignina/análise , Proteínas de Plantas , Plantas Geneticamente Modificadas/enzimologia , Populus/enzimologia
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