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1.
Zhongguo Zhong Yao Za Zhi ; 44(17): 3798-3805, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31602956

RESUMO

Based on metabolomics,the metabolites of larvae zebrafish with overdose of Panax notoginseng saponins( PNS) were compared with those in normal group of larvae zebrafish to investigate the possible toxicity mechanism of overdose PNS in larvae zebrafish. An experimental animal model of long-term toxicity induced by PNS overdose was established by administering 1-6 dpf at low,medium and high doses of PNS,respectively. The ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry( UPLC-Q-TOF-MS) technique was combined with principal component analysis( PCA) and orthogonal partial least squares discriminant analysis( OPLS-DA) to screen and identify biomarkers associated with toxicity,and then the MetaboAnalyst database was used to analyze metabolism-related pathways. The results showed that the metabolites of each group could be distinguished distinctly,and they deviated more from the normal group in a time and dose dependent manner. Twenty-nine potential biomarkers related to toxicity( VIP>1,P<0. 05) were identified preliminarily,mainly involving six metabolic pathways. From the metabonomics point of view,the toxicity mechanism of overdose PNS may be related to the disorders of lipid metabolism,amino acid metabolism and energy metabolism.


Assuntos
Metabolômica , Panax notoginseng/toxicidade , Saponinas/toxicidade , Aminoácidos/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Metabolismo Energético , Larva/efeitos dos fármacos , Metabolismo dos Lipídeos , Espectrometria de Massas , Testes de Toxicidade Aguda , Peixe-Zebra
2.
J Agric Food Chem ; 67(37): 10513-10520, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31475823

RESUMO

Amino acids can stimulate milk fat synthesis, but the underlying molecular mechanism is still largely unknown. In this study, we studied the regulatory role and corresponding molecular mechanism of cAMP response element-binding protein-regulated transcription coactivator 2 (CRTC2) in amino acid-induced milk fat synthesis in mammary epithelial cells. We showed that leucine and methionine stimulated CRTC2 but not p-CRTC2(Ser171) expression and nuclear localization in cow mammary epithelial cells. Knockdown of CRTC2 decreased milk fat synthesis and sterol regulatory element binding protein 1c (SREBP-1c) expression and activation, whereas its overexpression had the opposite effects. Neither knockdown nor overexpression of CRTC2 affected ß-casein synthesis and phosphorylation of the machanistic target of rapamycin (mTOR), suggesting that CRTC2 only regulates milk fat synthesis. CRTC2 knockdown abolished the stimulation of leucine and methionine on SREBP-1c expression and activation. Knockdown or overexpression of CRTC2 did not affect the protein level of cAMP-response element-binding protein (CREB) and its phosphorylation but decreased or increased the binding of p-CREB to the promoter of SREBP-1c gene and its mRNA expression, respectively. Mutation of Ser171 of CRTC2 did not alter the stimulation of CRTC2 on SREBP-1c expression and activation, further suggesting that CRTC2 functions in the nucleus. mTOR inhibition by rapamycin totally blocked the stimulation of leucine and methionine on CRTC2 expression. The expression of CRTC2 was dramatically higher in the mouse mammary gland of lactation period, compared with that of the dry and puberty periods, whereas p-CRTC2(Ser171) was not changed, further supporting that CRTC2 is a key transcription coactivator for milk fat synthesis. These results uncover that CRTC2 is a key transcription coactivator of amino acid-stimulated mTOR-mediated milk fat synthesis in mammary epithelial cells.


Assuntos
Aminoácidos/metabolismo , Bovinos/metabolismo , Células Epiteliais/metabolismo , Gorduras/metabolismo , Glândulas Mamárias Animais/citologia , Leite/metabolismo , Fatores de Transcrição/metabolismo , Animais , Bovinos/genética , Feminino , Glândulas Mamárias Animais/metabolismo , Camundongos , Fosforilação , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Fatores de Transcrição/genética
3.
J Agric Food Chem ; 67(38): 10667-10677, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31483636

RESUMO

This study investigated the modulatory effects of Decaisnea insignis seed oil (DISO), which was rich in palmitoleic acid (55.25%), palmitic acid (12.25%), and oleic acid (28.74%), on alcohol-induced metabolism disorder in mice. Fifty mice were orally administered with 38% alcohol (0.4 mL/day) and without or with DISO (3, 6, and 12 g/kg) for consecutive 12 weeks. DISO inhibited the alcohol-induced weight loss and liver function abnormality (p < 0.01) and shifted the profiles of cecal microbiome: elevating the abundance of Lactobacillus, Ruminoccoceae_UCG_004 (p < 0.05) and decreasing abundance of Parabacteroides (p < 0.05). This treatment also regulated metabolome response of amino acid and lipid metabolism in cecal content: upregulating 5-hydroxyindole-3-acetic acid (p < 0.05), 6-hydroxynicotinic acid, 5-methoxytryptamine, nicotinamide, and nicotinic acid (p < 0.1) and downregulating androsterone, tryptophan, and indole-3-acetamide (p < 0.05). DISO protected against alcoholic liver injury and gut microbiota dysbiosis by enriching the relative abundance of Lactobacillus, which was positively associated with the improvement of intestinal permeability and tryptophan metabolism.


Assuntos
Álcoois/efeitos adversos , Disbiose/prevenção & controle , Microbioma Gastrointestinal/efeitos dos fármacos , Hepatopatias Alcoólicas/prevenção & controle , Magnoliopsida/química , Óleos Vegetais/administração & dosagem , Consumo de Bebidas Alcoólicas/efeitos adversos , Aminoácidos/metabolismo , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Ceco/efeitos dos fármacos , Ceco/microbiologia , Disbiose/metabolismo , Disbiose/microbiologia , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Hepatopatias Alcoólicas/metabolismo , Hepatopatias Alcoólicas/microbiologia , Masculino , Metaboloma/efeitos dos fármacos , Camundongos , Microbiota/efeitos dos fármacos , Sementes/química
4.
BMC Evol Biol ; 19(1): 158, 2019 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-31362700

RESUMO

BACKGROUND: There is wide agreement that only a subset of the twenty standard amino acids existed prebiotically in sufficient concentrations to form functional polypeptides. We ask how this subset, postulated as {A,D,E,G,I,L,P,S,T,V}, could have formed structures stable enough to found metabolic pathways. Inspired by alphabet reduction experiments, we undertook a computational analysis to measure the structural coding behavior of sequences simplified by reduced alphabets. We sought to discern characteristics of the prebiotic set that would endow it with unique properties relevant to structure, stability, and folding. RESULTS: Drawing on a large dataset of single-domain proteins, we employed an information-theoretic measure to assess how well the prebiotic amino acid set preserves fold information against all other possible ten-amino acid sets. An extensive virtual mutagenesis procedure revealed that the prebiotic set excellently preserves sequence-dependent information regarding both backbone conformation and tertiary contact matrix of proteins. We observed that information retention is fold-class dependent: the prebiotic set sufficiently encodes the structure space of α/ß and α + ß folds, and to a lesser extent, of all-α and all-ß folds. The prebiotic set appeared insufficient to encode the small proteins. Assessing how well the prebiotic set discriminates native vs. incorrect sequence-structure matches, we found that α/ß and α + ß folds exhibit more pronounced energy gaps with the prebiotic set than with nearly all alternatives. CONCLUSIONS: The prebiotic set optimally encodes local backbone structures that appear in the folded environment and near-optimally encodes the tertiary contact matrix of extant proteins. The fold-class-specific patterns observed from our structural analysis confirm the postulated timeline of fold appearance in proteogenesis derived from proteomic sequence analyses. Polypeptides arising in a prebiotic environment will likely form α/ß and α + ß-like folds if any at all. We infer that the progressive expansion of the alphabet allowed the increased conformational stability and functional specificity of later folds, including all-α, all-ß, and small proteins. Our results suggest that prebiotic sequences are amenable to mutations that significantly lower native conformational energies and increase discrimination amidst incorrect folds. This property may have assisted the genesis of functional proto-enzymes prior to the expansion of the full amino acid alphabet.


Assuntos
Aminoácidos/metabolismo , Origem da Vida , Proteínas/química , Sequência de Aminoácidos , Método de Monte Carlo , Mutagênese/genética , Conformação Proteica , Domínios Proteicos , Dobramento de Proteína , Proteínas/genética
5.
Genes Dev ; 33(17-18): 1191-1207, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31371435

RESUMO

The vast majority of eukaryotes possess two DNA recombinases: Rad51, which is ubiquitously expressed, and Dmc1, which is meiosis-specific. The evolutionary origins of this two-recombinase system remain poorly understood. Interestingly, Dmc1 can stabilize mismatch-containing base triplets, whereas Rad51 cannot. Here, we demonstrate that this difference can be attributed to three amino acids conserved only within the Dmc1 lineage of the Rad51/RecA family. Chimeric Rad51 mutants harboring Dmc1-specific amino acids gain the ability to stabilize heteroduplex DNA joints with mismatch-containing base triplets, whereas Dmc1 mutants with Rad51-specific amino acids lose this ability. Remarkably, RAD-51 from Caenorhabditis elegans, an organism without Dmc1, has acquired "Dmc1-like" amino acids. Chimeric C. elegans RAD-51 harboring "canonical" Rad51 amino acids gives rise to toxic recombination intermediates, which must be actively dismantled to permit normal meiotic progression. We propose that Dmc1 lineage-specific amino acids involved in the stabilization of heteroduplex DNA joints with mismatch-containing base triplets may contribute to normal meiotic recombination.


Assuntos
Aminoácidos/metabolismo , Rad51 Recombinase/química , Rad51 Recombinase/metabolismo , Recombinases/química , Recombinases/metabolismo , Recombinação Genética/genética , Aminoácidos/genética , Animais , Pareamento Incorreto de Bases , Caenorhabditis elegans/enzimologia , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Sequência Conservada , Mutação , Rad51 Recombinase/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Recombinases/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
6.
J Agric Food Chem ; 67(36): 10048-10058, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31422666

RESUMO

Ginseng, the roots and rhizomes of Panax ginseng C. A. Meyer, is used not only as a herbal medicine but also as a functional food to support body functions. Ginsenoside Rg3 (GRg3) is a major bioactive component in ginseng. In this study, the beneficial effects of GRg3 on rats with Alzheimer's disease (AD) were evaluated via the behavioral experiment and antioxidant capacity. Moreover, metabolomic analysis based on UPLC-QTOF-MS/MS and apoptosis analysis was used to obtain the change between AD and GRg3-administrated rats to assess the underlying mechanisms on improving mitochondrial dysfunction. Results showed that GRg3 could prevent the cognitive impairment of AD rats by improving the mitochondrial dysfunction. The potential mechanisms were related to regulate the abnormality of energy metabolism, electron transport chain, amino acid metabolism, purine metabolism, and antiapoptosis. These findings support the exploitation of GRg3 as an effective complementary and functional food to prevent and delay AD.


Assuntos
Doença de Alzheimer/prevenção & controle , Doença de Alzheimer/psicologia , Medicamentos de Ervas Chinesas/administração & dosagem , Ginsenosídeos/administração & dosagem , Mitocôndrias/efeitos dos fármacos , Doença de Alzheimer/fisiopatologia , Aminoácidos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Cognição/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Humanos , Masculino , Mitocôndrias/metabolismo , Panax/química , Ratos , Ratos Wistar
7.
J Agric Food Chem ; 67(34): 9551-9559, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31379157

RESUMO

In oleaginous micro-organisms, nitrogen limitation activates adenosine monophosphate deaminase (AMPD) and promotes lipogenesis via the inhibition of isocitrate dehydrogenase. We found that the overexpression of homologous AMPD in Mortierella alpina favored lipid synthesis over cell growth. Total fatty acid content in the recombinant strain was 15.0-34.3% higher than that in the control, even though their biomass was similar. During the early fermentation stage, the intracellular AMP level reduced by 40-60%, together with a 1.9-2.7-fold increase in citrate content compared with the control, therefore provided more precursors for fatty acid synthesis. Moreover, the decreased AMP level resulted in metabolic reprogramming, reflected by the blocked TCA cycle and reduction of amino acids, distributing more carbon to lipid synthesis pathways. By coupling the energy balance with lipogenesis, this study provides new insights into cell metabolism under nitrogen-limited conditions and targets the regulation of fatty acid accumulation in oleaginous micro-organisms.


Assuntos
AMP Desaminase/metabolismo , Ácidos Graxos/metabolismo , Proteínas Fúngicas/metabolismo , Mortierella/enzimologia , AMP Desaminase/genética , Monofosfato de Adenosina/metabolismo , Aminoácidos/metabolismo , Proteínas Fúngicas/genética , Metabolismo dos Lipídeos , Mortierella/genética , Mortierella/crescimento & desenvolvimento , Mortierella/metabolismo
8.
J Anim Sci ; 97(8): 3274-3285, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31363781

RESUMO

Tryptophan (Trp) is an indispensable amino acid (AA) for dogs of all life stages; however, although Trp requirements for growing dogs are derived from 3 dose-response studies, there are no empirical data on Trp requirements for adult dogs at maintenance. The study objective was to determine Trp requirements of adult dogs of 3 different breeds using the indicator amino acid oxidation (IAAO) technique. Four spayed or neutered Miniature Dachshunds (5.28 ± 0.29 kg BW), 4 spayed Beagles (9.32 ± 0.41 kg BW), and 5 neutered Labrador Retrievers (30.51 ± 2.09 kg BW) were used. After a 14-d adaptation to a Trp-adequate basal diet (Trp = 0.482% dry matter), all dogs were fed a mildly Trp-deficient diet for 2 d (Trp = 0.092% dry matter) before being randomly allocated to receiving 1 of 7 concentrations of Trp supplementation (final Trp content in experimental diets was 0.092, 0.126, 0.148, 0.182, 0.216, 0.249, and 0.283% dry matter) and all dogs received all Trp treatments. After 2-d adaptation to the experimental diets, dogs underwent individual IAAO studies. Total feed was divided in 13 equal meals; at the sixth meal, dogs were fed a bolus of L-[1-13C]-Phenylalanine (Phe) (9.40 mg/kg BW), and thereafter, L-[1-13C]-Phe was supplied (2.4 mg/kg BW) with every meal. Total production of 13CO2 during isotopic steady state was determined by enrichment of 13CO2 in breath samples and total production of CO2 measured using indirect calorimetry. The maintenance requirement for Trp and the 95% confidence interval (CI) were determined using a 2-phase linear regression model. Mean Trp requirements were estimated at 0.154, 0.218, and 0.157% (dry-matter) for Dachshunds, Beagles, and Labradors, respectively. The upper 95% CI were 0.187, 0.269, and 0.204% (dry-matter) for Dachshunds, Beagles, and Labradors. In conclusion, estimated Trp requirements are higher for Beagles compared with Labradors or Dachshunds, and all estimated requirements are higher than those currently recommended by the NRC and AAFCO.


Assuntos
Aminoácidos/metabolismo , Cães/fisiologia , Necessidades Nutricionais , Triptofano/metabolismo , Aminoácidos Essenciais/metabolismo , Animais , Tamanho Corporal , Peso Corporal , Calorimetria Indireta/veterinária , Dieta/veterinária , Feminino , Masculino , Oxirredução , Fenilalanina/metabolismo , Distribuição Aleatória , Especificidade da Espécie
9.
Bioresour Technol ; 291: 121882, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31377512

RESUMO

The aim of this study is to assess the effectiveness of protein-like precursors addition on promoting humification process during lignocellulose-like biomass composting through adding amino acids to compost. The humification indexes of R1 and R2 was significantly higher than that of CK (P < 0.05). The decreasing ratio of Maillard precursor concentration of R2 and R1 was higher than CK. Amino acids addition affected the bacteria community and environmental factors during composting. Variance partitioning analysis showed that humification process was strengthened with environmental factors, bacteria community, Maillard precursors. Structural equation model (SEM) analysis showed that amino acids had substantial impact on promoting humic acid (HA) formation. The combined application of protein-like wastes and lignocellulose-like wastes was suggested to improve carbon sequestration. This study lays a foundation for economically and effectively managing different types of straws by composting.


Assuntos
Aminoácidos/metabolismo , Biomassa , Compostagem , Lignina/metabolismo , Precursores de Proteínas/farmacologia , Substâncias Húmicas/análise
10.
Bioresour Technol ; 291: 121873, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31377506

RESUMO

Cholinium-glycinate ([Ch][Gly]) and cholinium-alanate ([Ch][Ala]) were investigated on the pretreatment of mulberry stem (MS). It resulted in an increase of glucose from 14% to more than 74% compared to the untreated sample. Pretreatment by reused [Ch][Gly] showed good performance for delignification of >60%, and improved structural polysaccharide digestion. Each fractional component has high potential for lignin purification, and succinic acid fermentation. The extracted lignin with [Ch][Gly] showed >90% purity with good qualities of aromatic unit as confirmed by FT-IR and 1H NMR spectra. The carbohydrate rich material was employed for succinic acid fermentation with the highest yield of succinic acid more than 0.89 gsuccinic acid/gglucose. After purification, poly(butylene) succinate (PBS) was synthesized, and was characterized in comparison to commercial PBS.


Assuntos
Butileno Glicóis/metabolismo , Fermentação , Morus/metabolismo , Polímeros/metabolismo , Ácido Succínico/metabolismo , Aminoácidos/metabolismo , Glucose/metabolismo , Líquidos Iônicos/química , Lignina/química
11.
Life Sci ; 234: 116778, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31430454

RESUMO

AIMS: To clarify the role of the gut-brain axis in depression. MAIN METHODS: We used the iTRAQ technique to identify differential proteins in the intestine of the rat model of chronic unpredictable mild stress (CUMS)-induced depression. Significant differential proteins were subjected to Gene Ontology (GO) functional annotations and KEGG pathway enrichment analysis. Key proteins were validated at the mRNA and protein levels. The levels of cytokines in the intestine, serum and hypothalamus were examined by ELISA. HPLC-UV was used to detect the levels of amino acids. KEY FINDINGS: In the rat intestine, 349 differential proteins (209 downregulated, 140 upregulated) were identified. GO analysis indicated that "protein complex assembly" was the first-ranked biological process. SNARE complex components, including SNAP23, VAMP3 and VAMP8, were increased at the mRNA levels, while only VAMP3 and VAMP8 were also upregulated at the protein level. TNFα, IL6 and IL1ß were upregulated in the CUMS rat intestine, while TNFα was decreased in the serum and hypothalamus. IL1ß was decreased in the serum. "Protein digestion and absorption" was the most significantly enriched KEGG pathway, involving 5 differential proteins: SLC9A3, ANPEP, LAT1, ASCT2 and B0AT1. Glutamine, glycine and aspartic acid were perturbed in the CUMS rat intestine. SIGNIFICANCE: Our findings suggest that CUMS enhances the adaptive immune response in the intestine through ER-phagosome pathway mediated by SNARE complex and disturb absorption of amino acids. It advances our understanding of the role of gut-brain axis in depression and provides a potential therapeutic target for the disease.


Assuntos
Aminoácidos/análise , Citocinas/análise , Depressão/patologia , Mucosa Intestinal/metabolismo , Intestinos/patologia , Proteínas SNARE/análise , Aminoácidos/metabolismo , Animais , Citocinas/genética , Depressão/etiologia , Depressão/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica , Absorção Intestinal , Masculino , Proteômica , Ratos , Ratos Sprague-Dawley , Proteínas SNARE/genética , Estresse Psicológico/complicações
12.
Food Chem ; 300: 125169, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31336273

RESUMO

Red drupelet is a postharvest disorder of blackberries with several drupelets turning back to red. This affects visual quality and thus marketability and consumers' acceptance. However, the cause of this disorder as well as metabolite changes during color reversion have not been fully understood. Anthocyanins, cyanidin 3-glucoside, cyanidin 3-malonylglucoside, cyanidin 3-dioxalylglucoside, and total anthocyanin, were significantly lower in red drupelets than in black drupelets after 7 days of storage. Sugars and organic acids, lipids, and free amino acids also changed with storage and by color reversion. The untargeted metabolomics analyses indicated that red drupelets were generally differentiated from berries at harvest or black drupelets at metabolite level. The results of this study help better understand the red drupelet disorder. To our knowledge, this is the first study investigating red drupelet disorder by comparing black and red drupelets at metabolite level.


Assuntos
Metabolômica/métodos , Rubus/metabolismo , Aminoácidos/análise , Aminoácidos/metabolismo , Antocianinas/análise , Antocianinas/metabolismo , Cor , Qualidade dos Alimentos , Armazenamento de Alimentos , Frutas/química , Glucosídeos/análise , Glucosídeos/metabolismo , Lipídeos/análise , Rubus/química
13.
J Agric Food Chem ; 67(29): 8235-8242, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31260295

RESUMO

This research aims to analyze the biosynthetic pathway of endogenous semicarbazide (SEM) in shrimps using Litopenaeus vannamei as the model target. To achieve this objective, the content of SEM in L. vannamei throughout the whole growth cycle was monitored under the strict control of external environmental interference. Experimental results showed that SEM was found in the shrimp shell at all stages, with its content decreasing first and then increasing, and no SEM was detected in the shrimp muscle of each growth stage. This indicated that endogenous SEM in L. vannamei was derived from the shrimp shell. At the same time, the content of amino acids in the shrimp shell and the corresponding substances involved in the urea cycle in the entire growth cycle of shrimp were monitored. The correlation analysis between them and the changes in the SEM content in shrimp showed that arginine had the largest correlation coefficient (0.952) with the changes in the SEM content. The main substances of the urea cycle may be related to the production of SEM. In combination with the water environmental test of high ammonia nitrogen, it was presumed that the formation of endogenous SEM was related to the amidine group of arginine and amide structure of citrulline and urea. Arginine, citrulline, and urea in the urea cycle of L. vannamei eventually produced SEM via an oxaziridine intermediate under the action of hydrogen peroxide and ammonia, and a standardized reaction test was conducted to verify the hypothesis and, thus, provided a new idea for future endogenous SEM research.


Assuntos
Penaeidae/crescimento & desenvolvimento , Semicarbazidas/análise , Semicarbazidas/metabolismo , Aminoácidos/análise , Aminoácidos/metabolismo , Amônia/metabolismo , Exoesqueleto/química , Exoesqueleto/metabolismo , Animais , Vias Biossintéticas , Penaeidae/química , Penaeidae/metabolismo
14.
World J Microbiol Biotechnol ; 35(8): 118, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31332540

RESUMO

The fungal genus Ustilago consists of intimidating pathogens associated with disease manifestations in plants of agricultural importance and gravity. Rapid progress of genome sequencing has opened the floodgates for biological research. Availability of Ustilago genomes provides a scope to explore complex codon and amino acid usage patterns in the genus. An extensive scrutiny of the factors underlying the complex modalities of codon and amino acid usage in Ustilago has been executed in the present analysis. Multivariate statistical analysis revealed a dominant effect of natural selection pressure, aimed at translational accuracy, to be operative on the codon usage behavior. Subtle impact of GC compositional constraint was also evident on the codon usage patterns. Gene expressivity was inferred to be the most crucial determinant governing observed codon usage variations. Amino acid usage patterns were found to be significantly governed by aromatic and hydrophobic characters of the encoded proteins. GC content and length of protein coding sequences also had considerable influence on the amino acid usage signatures. Extensive analysis of codon context variations revealed that UpA dinucleotides were strictly avoided at the codon-codon junctions (cP3-cA1) which might be attributed to reduce the risk of nonsense mutations and subsequently, improve translational finesse. Identification of the optimal codons, employed preferentially among the genes with high expressivity, and estimation of preferred and avoided codon pairs in Ustilago promises to be useful pertaining to mutational experiments at the codonic level, targeted to thwart the growth of Ustilago and combat associated pathogenesis.


Assuntos
Perfilação da Expressão Gênica , Ustilago/genética , Aminoácidos/metabolismo , Composição de Bases/genética , Códon , Seleção Genética/genética , Ustilago/metabolismo , Sequenciamento Completo do Genoma
15.
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
16.
J Agric Food Chem ; 67(31): 8476-8484, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31298527

RESUMO

Cicada flowers, which are edible and medicinal mushrooms, are the fruiting bodies of Isaria cicadae, a fungus that is parasitic on the larvae of cicada pupae. We hypothesize that host factors might possess stimulatory activity on metabolite synthesis in Isaria cicadae. Here, we first compared the microbial community structures of different wild cicada flowers across geographical regions, compartments, and growth stages via high-throughput sequencing. Isaria cicadae TZC-3, an isolate of the most abundant operational taxonomic unit (OTU6782) in all the fungal communities, was isolated from wild cicada flowers. Furthermore, the effects of cicada pupae on metabolite synthesis in Isaria cicadae TZC-3 were studied in submerged culture. The contents of intercellular polysaccharides, adenosine, N6-(2-hydroxyethyl)-adenosine, free amino acids, and hydrolyzed monosaccharides in the mycelia cultured with cicada pupa powder (4%) were significantly increased as compared with the contents in the control group. This indicates that a cicada pupa can act as an elicitor for metabolite synthesis in Isaria cicadae.


Assuntos
Cordyceps/metabolismo , Carpóforos/química , Hemípteros/microbiologia , Pupa/microbiologia , Adenosina/análise , Adenosina/metabolismo , Aminoácidos/análise , Aminoácidos/metabolismo , Animais , Cordyceps/química , Cordyceps/crescimento & desenvolvimento , Carpóforos/crescimento & desenvolvimento , Carpóforos/metabolismo , Hemípteros/química , Hemípteros/metabolismo , Interações Hospedeiro-Patógeno , Microbiota , Micélio/química , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Pupa/química , Pupa/metabolismo
17.
J Agric Food Chem ; 67(31): 8441-8451, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31339045

RESUMO

The increase in the atmospheric CO2 concentration is predicted to influence wheat production and grain quality and nutritional properties. In the present study, durum wheat (Triticum durum Desf. cv. Sula) was grown under two different CO2 (400 versus 700 µmol mol-1) concentrations to examine effects on the crop yield and grain quality at different phenological stages (from grain filling to maturity). Exposure to elevated CO2 significantly increased aboveground biomass and grain yield components. Growth at elevated CO2 diminished the elemental N content as well as protein and free amino acids, with a typical decrease in glutamine, which is the most represented amino acid in grain proteins. Such a general decrease in nitrogenous compounds was associated with altered kinetics of protein accumulation, N remobilization, and N partitioning. Our results highlight important modifications of grain metabolism that have implications for its nutritional quality.


Assuntos
Dióxido de Carbono/metabolismo , Sementes/crescimento & desenvolvimento , Triticum/metabolismo , Aminoácidos/química , Aminoácidos/metabolismo , Dióxido de Carbono/análise , Cinética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Sementes/química , Sementes/metabolismo , Triticum/química , Triticum/crescimento & desenvolvimento
18.
Sci Total Environ ; 688: 567-573, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31254822

RESUMO

Aquatic invertebrates vary in methylmercury (MeHg) levels among systems which has been attributed, in part, to environmental conditions, but may also be linked to differences in their biochemical composition. As MeHg is known to bind to thiol-containing amino acids such as cysteine in proteins of fish, our objective was to determine if these amino acids explain MeHg variability among aquatic invertebrate taxa. Benthic macroinvertebrates from diverse functional feeding groups and bulk zooplankton were collected from six acidic lakes in Kejimkujik National Park, Nova Scotia, Canada, and analyzed for MeHg, cysteine (as cysteic acid), methionine (as methionine sulfone), and nitrogen (relative trophic level, δ15N) and carbon (carbon source, δ13C) isotopes. MeHg was significantly and positively related to cysteine or methionine in zooplankton, caddisfly and stonefly tissues (R2 from 0.24 to 0.57). In addition, methionine or cysteine in combination with δ15N and/or δ13C were better predictors of MeHg levels in stoneflies, mayflies, caddisflies and zooplankton among these lakes (R2adj = 0.25-0.91). Overall, these novel findings suggest that the variability in MeHg of aquatic invertebrates can be explained, in part, by their tissue levels of thiol-containing amino acids.


Assuntos
Aminoácidos/metabolismo , Organismos Aquáticos/metabolismo , Invertebrados/metabolismo , Compostos de Metilmercúrio/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Monitoramento Ambiental , Nova Escócia , Compostos de Sulfidrila
19.
J Dairy Sci ; 102(8): 7102-7117, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31155260

RESUMO

Alternative protein sources such as microalgae and faba beans may have environmental benefits over rapeseed. We studied the effects of rapeseed meal (RSM) or faba beans (FB) as a sole protein feed or as protein feeds partially substituted with Spirulina platensis (spirulina) microalgae on milk production, N utilization, and AA metabolism of dairy cows. Eight multiparous Finnish Ayrshire cows (113 ± 36.3 d in milk; mean ± SD) were used in a balanced, replicated 4 × 4 Latin square with 2 × 2 factorial arrangement of treatments and 21-d periods. Four cows in one Latin square were rumen cannulated. Treatments were 2 isonitrogenously fed protein sources, RSM or rolled FB, or one of these sources with half of its crude protein substituted by spirulina (RSM-SPI and FB-SPI). Cows had ad libitum access to total mixed rations consisting of grass silage, barley, sugar beet pulp, minerals, and experimental protein feed. The substitution of RSM with FB did not affect dry matter intake (DMI) but decreased neutral detergent fiber intake and increased the digestibility of other nutrients. Spirulina in the diet decreased DMI and His intake. Spirulina had no effect on Met intake in cows on RSM diets but increased it in those on FB diets. Energy-corrected milk (ECM) and protein yields were decreased when RSM was substituted by FB. Milk and lactose yields were decreased in cows on the RSM-SPI diet compared with the RSM diet but increased in those on FB-SPI compared with FB. The opposite was true for milk fat and protein concentrations; thus, spirulina in the diet did not affect ECM. Feed conversion efficiency (ECM:DMI) increased in cows on FB diets with spirulina, whereas little effect was observed for those on RSM diets. The substitution of RSM by FB decreased arterial concentration of Met and essential AA. Spirulina in the diet increased milk urea N and ruminal NH4-N and decreased the efficiency of N utilization in cows on RSM diets, whereas those on FB diets showed opposite results. Met likely limited milk production in cows on the FB diet as evidenced by the decrease in arterial Met concentration and milk protein yield when RSM was substituted by FB. The results suggest the potential to improve milk production response to faba beans with supplementation of Met-rich feeds such as spirulina. This study also confirmed spirulina had poorer palatability than RSM and FB despite total mixed ration feeding and lower milk production when spirulina partially replaced RSM.


Assuntos
Aminoácidos/metabolismo , Bovinos/fisiologia , Microalgas , Leite/metabolismo , Nitrogênio/metabolismo , Spirulina , Animais , Brassica rapa , Dieta/veterinária , Feminino , Lactação , Lactose/análise , Leite/efeitos dos fármacos , Proteínas do Leite/análise , Silagem/análise , Vicia faba
20.
Food Microbiol ; 83: 71-85, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31202421

RESUMO

Nitrogen is an essential nutrient for yeast during alcoholic fermentation. Nitrogen is involved in the biosynthesis of protein, amino acids, nucleotides, and other metabolites, including volatile compounds. However, recent studies have called several mechanisms that regulate its role in biosynthesis into question. An initial focus on S. cerevisiae has highlighted that the concept of "preferred" versus "non-preferred" nitrogen sources is extremely variable and strain-dependent. Then, the direct involvement of amino acids consumed in the formation of proteins and volatile compounds has recently been reevaluated. Indeed, studies have highlighted the key role of lipids in nitrogen regulation in S. cerevisiae and their involvement in the mechanism of cell death. New winemaking strategies using non-Saccharomyces yeast strains in co- or sequential fermentation improve nitrogen management. Indeed, recent studies show that non-Saccharomyces yeasts have significant and specific needs for nitrogen. Moreover, sluggish fermentation can occur when they are associated with S. cerevisiae, necessitating nitrogen addition. In this context, we will present the consequences of nitrogen addition, discussing the sources, time of addition, transcriptome changes, and effect on volatile compound composition.


Assuntos
Fermentação , Nitrogênio/metabolismo , Saccharomyces cerevisiae/metabolismo , Vinho/microbiologia , Aminoácidos/metabolismo , Saccharomyces cerevisiae/genética , Compostos Orgânicos Voláteis/metabolismo
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