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  1 / 1957 MEDLINE  
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[PMID]:28450424
[Au] Autor:Wang L; Kong D; Lv Q; Niu G; Han T; Zhao X; Meng S; Cheng Q; Guo S; Du J; Wu Z; Wang J; Bao F; Hu Y; Pan X; Xia J; Yuan D; Han L; Lian T; Zhang C; Wang H; He XJ; He YK
[Ad] Endereço:College of Life Sciences (L.W., D.K., Q.L., G.N., T.H., X.Z., S.M., Q.C., S.G., J.D., J.W., F.B., Y.H., X.P., J.X., Y.-k.H.) and Department of Chemistry (D.K.), Capital Normal University, Beijing 100048, China.
[Ti] Título:Tetrahydrofolate Modulates Floral Transition through Epigenetic Silencing.
[So] Source:Plant Physiol;174(2):1274-1284, 2017 Jun.
[Is] ISSN:1532-2548
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Folates, termed from tetrahydrofolate (THF) and its derivatives, function as coenzymes in one-carbon transfer reactions and play a central role in synthesis of nucleotides and amino acids. Dysfunction of cellular folate metabolism leads to serious defects in plant development; however, the molecular mechanisms of folate-mediated cellular modifications and physiological responses in plants are still largely unclear. Here, we reported that THF controls flowering time by adjusting DNA methylation-regulated gene expression in Arabidopsis ( ). Wild-type seedlings supplied with THF as well as the high endogenous THF content mutant exhibited significant up-regulation of the flowering repressor of and thereby delaying floral transition in a dose-dependent manner. Genome-wide transcripts and DNA methylation profiling revealed that THF reduces DNA methylation so as to manipulate gene expression activity. Moreover, in accompaniment with elevated cellular ratios between monoglutamylated and polyglutamylated folates under increased THF levels, the content of -adenosylhomo-Cys, a competitive inhibitor of methyltransferases, was obviously higher, indicating that enhanced THF accumulation may disturb cellular homeostasis of the concerted reactions between folate polyglutamylation and folate-dependent DNA methylation. In addition, we found that the loss-of-function mutant of CG DNA methyltransferase MET1 displayed much less responsiveness to THF-associated flowering time alteration. Taken together, our studies revealed a novel regulatory role of THF on epigenetic silencing, which will shed lights on the understanding of interrelations in folate homeostasis, epigenetic variation, and flowering control in plants.
[Mh] Termos MeSH primário: Arabidopsis/genética
Arabidopsis/fisiologia
Epigênese Genética/efeitos dos fármacos
Flores/genética
Inativação Gênica/efeitos dos fármacos
Tetra-Hidrofolatos/farmacologia
[Mh] Termos MeSH secundário: Metilação de DNA/efeitos dos fármacos
Metilação de DNA/genética
Flores/efeitos dos fármacos
Perfilação da Expressão Gênica
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos
Genoma de Planta
Ácido Poliglutâmico/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Tetrahydrofolates); 25513-46-6 (Polyglutamic Acid)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180115
[Lr] Data última revisão:
180115
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE
[do] DOI:10.1104/pp.16.01750


  2 / 1957 MEDLINE  
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[PMID]:28988145
[Au] Autor:Miranda BNM; Fotoran WL; Canduri F; Souza DHF; Wunderlich G; Carrilho E
[Ad] Endereço:Instituto de Química de São Carlos, Universidade de São Paulo, Av. Trabalhador São-carlense, 400, 13566-590 São Carlos, SP, Brazil; Instituto Nacional de Ciência e Tecnologia de Bioanalítica - INCTBio, 13083-970, Campinas, SP, Brazil.
[Ti] Título:Heterologous expression of Homo sapiens alpha-folate receptors in E. coli by fusion with a trigger factor for enhanced solubilization.
[So] Source:Protein Expr Purif;142:75-80, 2018 Feb.
[Is] ISSN:1096-0279
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The role of Alpha folate receptors (FRα) in folate metabolism and cancer development has been extensively studied. The reason for this is not only associated to its direct relation to disease development but also to its potential use as a highly sensitive and specific biomarker for cancers therapies. Over the recent years, the crystal structures of human FRα complexed with different ligands were described relying on an expensive and time-consuming production process. Here, we constructed an efficient system for the expression and purification of a human FRα in E. coli. Unlike a conventional expression method we used a specific protein fusion expressing the target protein together with a trigger factor (TF). This factor is a chaperone from E. coli that assists the correct folding of newly synthesized polypeptide chains. The activity of rTFFRα was comparable to glycosylphosphatidylinositol (GPI) anchored proteins extracted from HeLa tumor cells. Our work demonstrates a straightforward and versatile approach for the production of active human FRα by heterologous expression; this approach further enhances the development of inhibition studies and biotechnological applications. The purified product was then conjugated to liposomes, obtaining a 35% higher signal from densitometry measurement on the immunoblotting assay in the contruct containing the Ni-NTA tag, as a mimesis of an exosome, which is of vital importance to nanotherapeutic techniques associated to treatment and diagnosis of tumors.
[Mh] Termos MeSH primário: Proteínas de Escherichia coli/genética
Receptor 1 de Folato/genética
Peptidilprolil Isomerase/genética
Plasmídeos/química
Proteínas Recombinantes de Fusão/genética
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Clonagem Molecular
Escherichia coli/genética
Escherichia coli/metabolismo
Proteínas de Escherichia coli/metabolismo
Receptor 1 de Folato/metabolismo
Expressão Gênica
Células HeLa
Histidina/genética
Histidina/metabolismo
Seres Humanos
Cinética
Lipossomos/química
Lipossomos/metabolismo
Oligopeptídeos/genética
Oligopeptídeos/metabolismo
Peptidilprolil Isomerase/metabolismo
Plasmídeos/metabolismo
Proteólise
Proteínas Recombinantes de Fusão/metabolismo
Tetra-Hidrofolatos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Escherichia coli Proteins); 0 (FOLR1 protein, human); 0 (Folate Receptor 1); 0 (His-His-His-His-His-His); 0 (Liposomes); 0 (Oligopeptides); 0 (Recombinant Fusion Proteins); 0 (Tetrahydrofolates); 43ZWB253H4 (5,6,7,8-tetrahydrofolic acid); 4QD397987E (Histidine); EC 5.2.1.- (trigger factor, E coli); EC 5.2.1.8 (Peptidylprolyl Isomerase)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171128
[Lr] Data última revisão:
171128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171009
[St] Status:MEDLINE


  3 / 1957 MEDLINE  
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[PMID]:28821425
[Au] Autor:Karunaratne K; Luedtke N; Quinn DM; Kohen A
[Ad] Endereço:Department of Chemistry, University of Iowa, Iowa City, IA 52242, USA.
[Ti] Título:Flavin-dependent thymidylate synthase: N5 of flavin as a Methylene carrier.
[So] Source:Arch Biochem Biophys;632:11-19, 2017 Oct 15.
[Is] ISSN:1096-0384
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Thymidylate is synthesized de novo in all living organisms for replication of genomes. The chemical transformation is reductive methylation of deoxyuridylate at C5 to form deoxythymidylate. All eukaryotes including humans complete this well-understood transformation with thymidylate synthase utilizing 6R-N -N -methylene-5,6,7,8-tetrahydrofolate as both a source of methylene and a reducing hydride. In 2002, flavin-dependent thymidylate synthase was discovered as a new pathway for de novo thymidylate synthesis. The flavin-dependent catalytic mechanism is different than thymidylate synthase because it requires flavin as a reducing agent and methylene transporter. This catalytic mechanism is not well-understood, but since it is known to be very different from thymidylate synthase, there is potential for mechanism-based inhibitors that can selectively inhibit the flavin-dependent enzyme to target many human pathogens with low host toxicity.
[Mh] Termos MeSH primário: Flavinas/química
Flavoproteínas/química
Tetra-Hidrofolatos/química
Timidilato Sintase/química
[Mh] Termos MeSH secundário: Flavinas/metabolismo
Flavoproteínas/metabolismo
Metilação
Tetra-Hidrofolatos/metabolismo
Timidina Monofosfato/biossíntese
Timidina Monofosfato/química
Timidilato Sintase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Flavins); 0 (Flavoproteins); 0 (Tetrahydrofolates); 365-07-1 (Thymidine Monophosphate); 7444-29-3 (5,10-methenyltetrahydrofolate); EC 2.1.1.45 (Thymidylate Synthase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171121
[Lr] Data última revisão:
171121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170820
[St] Status:MEDLINE


  4 / 1957 MEDLINE  
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[PMID]:28768831
[Au] Autor:Fazili Z; Sternberg MR; Paladugula N; Pfeiffer CM
[Ad] Endereço:Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA.
[Ti] Título:Two International Round-Robin Studies Showed Good Comparability of 5-Methyltetrahydrofolate but Poor Comparability of Folic Acid Measured in Serum by Different High-Performance Liquid Chromatography-Tandem Mass Spectrometry Methods.
[So] Source:J Nutr;147(9):1815-1825, 2017 Sep.
[Is] ISSN:1541-6100
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Serum folate methods produce different results. The comparability of HPLC-mass spectrometry (MS)/MS methods is not well documented. We conducted an international "round-robin" investigation to assess the comparability, precision, and accuracy of serum folate HPLC-MS/MS methods. The CDC laboratory, 7 laboratories with independently developed methods (group 1), and 6 laboratories with an adapted CDC method (group 2) analyzed folate forms in 6 serum pools and 6 calibrators from the CDC (duplicate analysis over 2 d) and in two 3-level reference materials (duplicate analysis). All laboratories measured 5-methyltetrahydrofolate (5-methylTHF) and folic acid; some measured additional folate forms. The geometric mean (range) concentrations (nanomoles per liter) for 5-methylTHF in the 6 serum pools were 18.3 nmol/L (CDC), 13.8-28.9 nmol/L (group 1), and 16.8-18.6 nmol/L (group 2); for folic acid the concentrations were 3.42 nmol/L (CDC), 1.09-4.74 nmol/L (group 1), and 1.74-2.90 nmol/L (group 2). The median imprecision (CV) for 5-methylTHF was 4.1% (CDC), 4.6-11% (group 1), and 1.7-6.0% (group 2); for folic acid it was 6.9% (CDC), 4.9-20% (group 1), and 3.9-23% (group 2). The mean ± SD (range) recovery of 5-methylTHF spiked into serum was 98% ± 27% (59-138%) for group 1 and 98% ± 10% (82-111%) for group 2; for folic acid it was 93% ± 29% (67-198%) for group 1 and 81% ± 16% (64-102%) for group 2. The mean relative bias for 5-methylTHF compared with the reference material certificate value was 12% (CDC), -24% to 30% (group 1), and -0.6% to 16% (group 2); for folic acid it was 73% (CDC), -47% to 578% (group 1), and -3.3% to 67% (group 2). For 5-methylTHF, group 2 laboratories demonstrated better agreement and precision, less variable spiking recovery, and less bias by using a reference material. Laboratory performance for folic acid was highly variable and needs improvement. Certified reference materials for serum folate forms and total folate are needed to improve method accuracy.
[Mh] Termos MeSH primário: Cromatografia Líquida de Alta Pressão/métodos
Ácido Fólico/sangue
Estado Nutricional
Espectrometria de Massas em Tandem/métodos
[Mh] Termos MeSH secundário: Calibragem
Seres Humanos
Laboratórios
Valores de Referência
Tetra-Hidrofolatos/sangue
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Tetrahydrofolates); 935E97BOY8 (Folic Acid); TYK22LML8F (5-methyltetrahydrofolate)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170913
[Lr] Data última revisão:
170913
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170804
[St] Status:MEDLINE
[do] DOI:10.3945/jn.117.254144


  5 / 1957 MEDLINE  
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[PMID]:28551248
[Au] Autor:Chandra-Hioe MV; Bucknall MP; Arcot J
[Ad] Endereço:ARC Training Centre for Advanced Technologies in Food Manufacture, School of Chemical Engineering, UNSW Australia, Sydney 2052, Australia. Electronic address: m.v.chandra-hioe@unsw.edu.au.
[Ti] Título:Evaluating folate extraction from infant milk formulae and adult nutritionals: Enzymatic digestion versus enzyme-free heat treatment.
[So] Source:Food Chem;234:365-371, 2017 Nov 01.
[Is] ISSN:0308-8146
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:This study compares enzymatic treatments to release folic acid (FA) and endogenous 5-methyltetrahydrofolate (5-MTHF) from infant milk formulae with enzyme-free heat extraction. The limits of detection and quantitation of FA were 1.4ng/mL and 3.1ng/mL, respectively; 7.5ng/mL and 16.2ng/mL for 5-MTHF. Absolute mean recoveries were 85% (FA) and 95% (5-MTHF). The RSD of the within-run variability was 6% and the inter-day variability was 8%. Averaged measurements of FA and 5-MTHF in SRM-1849a were within the certified value range. Analysed folate levels in three brands were greater than label values, because of inherently high 5-MTHF occurring in samples. The results indicate that enzyme-free heat treatment prior to UPLC-MS/MS analysis gives better sensitivity and reduces chromatographic interferences for the determination of FA and 5-MTHF in milk formulae than enzymatic treatments. Enzyme-free heat treatment is more compatible with UPLC-MS/MS than folate extraction techniques involving the addition of enzymes to milk.
[Mh] Termos MeSH primário: Enzimas/química
Ácido Fólico/análise
Manipulação de Alimentos/métodos
Temperatura Alta
Fórmulas Infantis/análise
[Mh] Termos MeSH secundário: Animais
Espectrometria de Massas em Tandem
Tetra-Hidrofolatos
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Enzymes); 0 (Tetrahydrofolates); 935E97BOY8 (Folic Acid)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170808
[Lr] Data última revisão:
170808
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170529
[St] Status:MEDLINE


  6 / 1957 MEDLINE  
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[PMID]:28429420
[Au] Autor:Harada A; Kamimura N; Takeuchi K; Yu HY; Masai E; Senda T
[Ad] Endereço:Structural Biology Research Center, Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki, Japan.
[Ti] Título:The crystal structure of a new O-demethylase from Sphingobium sp. strain SYK-6.
[So] Source:FEBS J;284(12):1855-1867, 2017 Jun.
[Is] ISSN:1742-4658
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In the cell, tetrahydrofolate (H folate) derivatives with a C1 unit are utilized in various ways, such as for the synthesis of amino acids and nucleic acids. While H folate derivatives with the C1 unit are typically produced in the glycine cleavage system, Sphingobium sp. strain SYK-6, which can utilize lignin-derived aromatic compounds as a sole source of carbon and energy, lacks this pathway, probably due to its unique nutrient requirements. In this bacterium, H folate-dependent O-demethylases in catabolic pathways for lignin-derived aromatic compounds seem to be involved in the C1 metabolism. LigM is one of the O-demethylases and catalyzes a C1-unit transfer from vanillate (VNL) to H folate. As the primary structure of LigM shows a similarity to T-protein in the glycine cleavage system, we hypothesized that LigM has evolved from T-protein, acquiring its unique biochemical and biological functions. To prove this hypothesis, structure-based understanding of its catalytic reaction is essential. Here, we determined the crystal structure of LigM in apo form and in complex with substrates and H folate. These crystal structures showed that the overall structure of LigM is similar to T-protein, but LigM has a few distinct characteristics, particularly in the active site. Structure-based mutational analysis revealed that His60 and Tyr247, which are not conserved in T-protein, are essential to the catalytic activity of LigM and their interactions with the oxygen atom in the methoxy group of VNL seem to facilitate a methyl moiety (C1-unit) transfer to H folate. Taken together, our structural data suggest that LigM has evolved divergently from T-protein. DATABASES: All atomic coordinates of the crystal structures determined in this study have been deposited to PDB. LigM: 5X1I, LigM-VNL complex: 5X1J, LigM-3-O-methylgallate complex: 5X1K, LigM-H folate complex: 5X1IL, LigM-H folate-protocatechuate (PCA) complex (P2 2 2): 5X1M, LigM-H folate-PCA complex (P3 21): 5X1N.
[Mh] Termos MeSH primário: Oxirredutases O-Desmetilantes/química
Sphingomonadaceae/enzimologia
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Aminometiltransferase/química
Cristalografia por Raios X
Modelos Moleculares
Oxirredutases O-Desmetilantes/metabolismo
Conformação Proteica
Homologia de Sequência de Aminoácidos
Tetra-Hidrofolatos/metabolismo
Ácido Vanílico/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Tetrahydrofolates); EC 1.- (Oxidoreductases, O-Demethylating); EC 2.1.2.10 (Aminomethyltransferase); GM8Q3JM2Y8 (Vanillic Acid)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170911
[Lr] Data última revisão:
170911
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170422
[St] Status:MEDLINE
[do] DOI:10.1111/febs.14085


  7 / 1957 MEDLINE  
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[PMID]:28367928
[Au] Autor:Luo S; Duan H; Zou Y; Qiu R; Wang C
[Ad] Endereço:Department of Food Science and Technology, Jinan University.
[Ti] Título:Quantification of Total Folate, Folate Species and Polyglutamyl Folate Distribution in Winged Beans (Psophocarus tetragonolobus (L) DC) from Different Cultivars and Growth Stages by Ultra-High Performance Liquid Chromatography Tandem Mass Spectrometry.
[So] Source:J Nutr Sci Vitaminol (Tokyo);63(1):69-80, 2017.
[Is] ISSN:1881-7742
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:Winged beans are an important natural source of some micronutrients. This paper presents the first complete characterization of folate derivatives including polyglutamyl 5-methyltetrahydrofolate (5-CH -H PteGlu ), folate species and total folate accumulating in pods and immature seeds of winged beans from 9 cultivars and 7 growth stages. 5-CH -H PteGlu and folate species were determined with a UHPLC-MS/MS method. Accurate determination of 5-CH -H PteGlu and folate species was optimized and validated according to EMA guidelines including method selectivity, sensitivity, linearity, accuracy, precision, matrix effect and carry-over. The level of total folate is in the range of 73-200 µg/100 g in the pods and 33-61 µg/100 g in the immature seeds. The predominant folate species in winged beans is 5-CH -H PteGlu . 5-CH -H PteGlu is the major polyglutamyl folate derivative. The level of total folate is increased about 4 fold with advancing maturity. For pods, the chain length is increased with growth which shifts from 5-CH -H PteGlu in the early stage to 5-CH -H PteGlu and 5-CH -H PteGlu in the 7th stage. Our findings demonstrate that winged beans are good source of folate. The validated UHPLC-MS/MS method allows for the determination of 5-CH -H PteGlu and folate species from other vegetable matrices.
[Mh] Termos MeSH primário: Cromatografia Líquida de Alta Pressão
Ácido Fólico/análise
Phaseolus/química
Sementes/química
Espectrometria de Massas em Tandem
Tetra-Hidrofolatos/análise
[Mh] Termos MeSH secundário: Sementes/crescimento & desenvolvimento
Especificidade da Espécie
Verduras/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Tetrahydrofolates); 935E97BOY8 (Folic Acid); TYK22LML8F (5-methyltetrahydrofolate)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170630
[Lr] Data última revisão:
170630
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170404
[St] Status:MEDLINE
[do] DOI:10.3177/jnsv.63.69


  8 / 1957 MEDLINE  
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[PMID]:28319664
[Au] Autor:Loveridge EJ; Hroch L; Hughes RL; Williams T; Davies RL; Angelastro A; Luk LY; Maglia G; Allemann RK
[Ad] Endereço:School of Chemistry, Cardiff University , Main Building, Park Place, Cardiff CF10 3AT, U.K.
[Ti] Título:Reduction of Folate by Dihydrofolate Reductase from Thermotoga maritima.
[So] Source:Biochemistry;56(13):1879-1886, 2017 Apr 04.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Mammalian dihydrofolate reductases (DHFRs) catalyze the reduction of folate more efficiently than the equivalent bacterial enzymes do, despite typically having similar efficiencies for the reduction of their natural substrate, dihydrofolate. In contrast, we show here that DHFR from the hyperthermophilic bacterium Thermotoga maritima can catalyze reduction of folate to tetrahydrofolate with an efficiency similar to that of reduction of dihydrofolate under saturating conditions. Nuclear magnetic resonance and mass spectrometry experiments showed no evidence of the production of free dihydrofolate during either the EcDHFR- or TmDHFR-catalyzed reductions of folate, suggesting that both enzymes perform the two reduction steps without release of the partially reduced substrate. Our results imply that the reaction proceeds more efficiently in TmDHFR than in EcDHFR because the more open active site of TmDHFR facilitates protonation of folate. Because T. maritima lives under extreme conditions where tetrahydrofolate is particularly prone to oxidation, this ability to salvage folate may impart an advantage to the bacterium by minimizing the squandering of a valuable cofactor.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Ácido Fólico/química
Prótons
Tetra-Hidrofolato Desidrogenase/química
Tetra-Hidrofolatos/química
Thermotoga maritima/enzimologia
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Domínio Catalítico
Escherichia coli/química
Escherichia coli/enzimologia
Escherichia coli/genética
Ácido Fólico/metabolismo
Expressão Gênica
Concentração de Íons de Hidrogênio
Cinética
NADP/química
NADP/metabolismo
Oxirredução
Dobramento de Proteína
Estrutura Secundária de Proteína
Especificidade da Espécie
Temperatura Ambiente
Tetra-Hidrofolato Desidrogenase/genética
Tetra-Hidrofolato Desidrogenase/metabolismo
Tetra-Hidrofolatos/metabolismo
Termodinâmica
Thermotoga maritima/química
Thermotoga maritima/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Protons); 0 (Tetrahydrofolates); 43ZWB253H4 (5,6,7,8-tetrahydrofolic acid); 53-59-8 (NADP); 935E97BOY8 (Folic Acid); EC 1.5.1.3 (Tetrahydrofolate Dehydrogenase)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170515
[Lr] Data última revisão:
170515
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170321
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.6b01268


  9 / 1957 MEDLINE  
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[PMID]:28298392
[Au] Autor:Page R; Robichaud A; Arbuckle TE; Fraser WD; MacFarlane AJ
[Ad] Endereço:Nutrition Research Division.
[Ti] Título:Total folate and unmetabolized folic acid in the breast milk of a cross-section of Canadian women.
[So] Source:Am J Clin Nutr;105(5):1101-1109, 2017 May.
[Is] ISSN:1938-3207
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Folate requirements increase during pregnancy and lactation. It is recommended that women who could become pregnant, are pregnant, or are lactating consume a folic acid (FA)-containing supplement. We sought to determine breast-milk total folate and unmetabolized folic acid (UMFA) contents and their relation with FA-supplement use and doses in a cohort of Canadian mothers who were enrolled in the MIREC (Maternal-Infant Research on Environmental Chemicals) study. Breast-milk tetrahydrofolate (THF), 5-methyl-THF, 5-formyl-THF, 5,10-methenyl-THF, and UMFA were measured with the use of liquid chromatography-tandem mass spectrometry ( = 561). Total daily supplemental FA intake was based on self-reported FA-supplement use. UMFA was detectable in the milk of 96.1% of the women. Total daily FA intake from supplements was associated with breast folate concentration and species. Breast-milk total folate was 18% higher ( < 0.001) in supplement users ( = 401) than in nonusers ( = 160), a difference driven by women consuming >400 µg FA/d ( ≤ 0.004). 5-Methyl-THF was 19% lower ( < 0.001) and UMFA was 126% higher ( < 0.001) in supplement users than in nonusers. Women who consumed >400 µg FA/d had proportionally lower 5-methyl-THF and higher UMFA than did women who consumed ≤400 µg FA/d. FA-supplement use was associated with modestly higher breast-milk total folate. Detectable breast-milk UMFA was nearly ubiquitous, including in women who did not consume an FA supplement. Breast-milk UMFA was proportionally higher than 5-methyl-THF in women who consumed >400 µg FA/d, thereby suggesting that higher doses exceed the physiologic capacity to metabolize FA and result in the preferential uptake of FA in breast milk. Therefore, FA-supplement doses >400 µg may not be warranted, especially in populations for whom FA fortification is mandatory.
[Mh] Termos MeSH primário: Suplementos Nutricionais
Ácido Fólico/farmacologia
Lactação/metabolismo
Leite Humano/metabolismo
[Mh] Termos MeSH secundário: Adulto
Mama
Canadá
Estudos de Coortes
Feminino
Ácido Fólico/análogos & derivados
Ácido Fólico/metabolismo
Seres Humanos
Necessidades Nutricionais
Gravidez
Tetra-Hidrofolatos/metabolismo
Complexo Vitamínico B/metabolismo
Complexo Vitamínico B/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Tetrahydrofolates); 12001-76-2 (Vitamin B Complex); 935E97BOY8 (Folic Acid); TYK22LML8F (5-methyltetrahydrofolate)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170719
[Lr] Data última revisão:
170719
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170317
[St] Status:MEDLINE
[do] DOI:10.3945/ajcn.116.137968


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[PMID]:27940130
[Au] Autor:Akiyama T; Hayashi Y; Hanaoka Y; Shibata T; Akiyama M; Nakamura K; Tsuyusaki Y; Kubota M; Yoshinaga H; Kobayashi K
[Ad] Endereço:Department of Child Neurology, Okayama University Hospital, Okayama, Japan. Electronic address: takiyama@okayama-u.ac.jp.
[Ti] Título:Simultaneous measurement of monoamine metabolites and 5-methyltetrahydrofolate in the cerebrospinal fluid of children.
[So] Source:Clin Chim Acta;465:5-10, 2017 Feb.
[Is] ISSN:1873-3492
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: We describe a new method for simultaneous measurement of monoamine metabolites (3-O-methyldopa [3-OMD], 3-methoxy-4-hydroxyphenylethyleneglycol [MHPG], 5-hydroxyindoleacetic acid [5-HIAA], and homovanillic acid [HVA]) and 5-methyltetrahydrofolate (5-MTHF) and its use on cerebrospinal fluid (CSF) samples from pediatric patients. METHODS: Monoamine metabolites and 5-MTHF were measured by high-performance liquid chromatography with fluorescence detection. CSF samples were prospectively collected from children according to a standardized collection protocol in which the first 1-ml fraction was used for analysis. RESULTS: Monoamine metabolites and 5-MTHF were separated within 10min. They showed linearity from the limit of detection to 1024nmol/l. The limit of quantification of each metabolite was sufficiently low for the CSF sample assay. In 42 CSF samples after excluding cases with possibly altered neurotransmitter profiles, the concentrations of 3-OMD, MHPG, 5-HIAA, HVA, and 5-MTHF showed significant age dependence and their ranges were comparable with the reference values in the literature. The metabolite profiles of aromatic l-amino acid decarboxylase deficiency, Segawa disease, and folate receptor α defect by this method were compatible with those in the literature. CONCLUSIONS: This method is a simple means of measuring CSF monoamine metabolites and 5-MTHF, and is especially useful for laboratories not equipped with electrochemical detectors.
[Mh] Termos MeSH primário: Di-Hidroxifenilalanina/análogos & derivados
Ácido Homovanílico/líquido cefalorraquidiano
Ácido Hidroxi-Indolacético/líquido cefalorraquidiano
Metoxi-Hidroxifenilglicol/líquido cefalorraquidiano
Tetra-Hidrofolatos/líquido cefalorraquidiano
[Mh] Termos MeSH secundário: Descarboxilases de Aminoácido-L-Aromático/líquido cefalorraquidiano
Descarboxilases de Aminoácido-L-Aromático/deficiência
Cromatografia Líquida de Alta Pressão/métodos
Di-Hidroxifenilalanina/líquido cefalorraquidiano
Distúrbios Distônicos/líquido cefalorraquidiano
Fluorescência
Receptor 1 de Folato/líquido cefalorraquidiano
Receptor 1 de Folato/deficiência
Receptor 1 de Folato/genética
Seres Humanos
Limite de Detecção
Distrofias Neuroaxonais/líquido cefalorraquidiano
Valores de Referência
Reprodutibilidade dos Testes
Tirosina/análogos & derivados
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (FOLR1 protein, human); 0 (Folate Receptor 1); 0 (Tetrahydrofolates); 42HK56048U (Tyrosine); 534-82-7 (Methoxyhydroxyphenylglycol); 54-16-0 (Hydroxyindoleacetic Acid); 63-84-3 (Dihydroxyphenylalanine); EC 4.1.1.28 (Aromatic-L-Amino-Acid Decarboxylases); EC 4.1.1.28 (DDC protein, human); TYK22LML8F (5-methyltetrahydrofolate); V3O7J20DWN (3-methoxytyrosine); X77S6GMS36 (Homovanillic Acid)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161213
[St] Status:MEDLINE



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