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1.
Data Brief ; 52: 110054, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38293577

RESUMEN

The application of image recognition in chemical experiments has the potential to enhance experiment recording and risk management. However, the current scarcity of suitable benchmarking datasets restricts the applications of machine vision techniques in chemical experiments. This data article presents an image dataset featuring common chemical apparatuses and experimenter's hands. The images have been meticulously annotated, providing detailed information for precise object detection through deep learning methods. The images were captured from videos filmed in organic chemistry laboratories. This dataset comprises a total of 5078 images including diverse backgrounds and situations surrounding the objects. Detailed annotations are provided in accompanying text files. The dataset is organized into training, validation, and test subsets. Each subset is stored within independent folders for easy access and utilization.

2.
Hum Cell ; 36(6): 2074-2086, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37610679

RESUMEN

The identification and development of therapeutic targets in cancer stem cells that lead to tumor development, recurrence, metastasis, and drug resistance is an important goal in cancer research. The hepatocellular carcinoma cell line Li-7 contains functionally different types of cells. Cells with tumor-forming activity are enriched in cancer stem cell-like CD13+CD166- cells and this cell population gradually decreases during culture in conventional culture medium (RPMI1640 containing 10% fetal bovine serum). When Li-7 cells are cultured in mTeSR1, a medium developed for human pluripotent stem cells, CD13+CD166- cells, and their tumorigenicity is maintained. Here, we sought to identify the mechanisms of tumorigenicity in this sub-population. We compared gene expression profiles of CD13+CD166- cells with other cell sub-populations and identified nine overexpressed genes (ENPP2, SCGN, FGFR4, MCOLN3, KCNJ16, SMIM22, SMIM24, SERPINH1, and TMPRSS2) in CD13+CD166- cells. After transfer from mTeSR1 to RPMI1640 containing 10% fetal bovine serum, the expression of these nine genes decreased in Li-7 cells and they lost tumorigenicity. In contrast, when these genes of Li-7 cells were forcibly expressed in cultures using RPMI1640 containing 10% fetal bovine serum, Li-7 cells maintained tumorigenicity. A metabolome analysis using capillary electrophoresis-mass spectrometry showed that two metabolic pathways, "Alanine, aspartate and glutamate metabolism" and "Arginine biosynthesis" were activated in cancer stem-cell-like cells. Our analyses here showed potential therapeutic target genes and metabolites for treatment of cancer stem cells in hepatocellular carcinoma.

4.
Nucleic Acids Res ; 51(14): 7602-7618, 2023 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-37260089

RESUMEN

To facilitate selfish replication, viruses halt host gene expression in various ways. The nuclear export of mRNA is one such process targeted by many viruses. SARS-CoV-2, the etiological agent of severe acute respiratory syndrome, also prevents mRNA nuclear export. In this study, Nsp14, a bifunctional viral replicase subunit, was identified as a novel inhibitor of mRNA nuclear export. Nsp14 induces poly(A)+ RNA nuclear accumulation and the dissolution/coalescence of nuclear speckles. Genome-wide gene expression analysis revealed the global dysregulation of splicing and 3'-end processing defects of replication-dependent histone mRNAs by Nsp14. These abnormalities were also observed in SARS-CoV-2-infected cells. A mutation introduced at the guanine-N7-methyltransferase active site of Nsp14 diminished these inhibitory activities. Targeted capillary electrophoresis-mass spectrometry analysis (CE-MS) unveiled the production of N7-methyl-GTP in Nsp14-expressing cells. Association of the nuclear cap-binding complex (NCBC) with the mRNA cap and subsequent recruitment of U1 snRNP and the stem-loop binding protein (SLBP) were impaired by Nsp14. These data suggest that the defects in mRNA processing and export arise from the compromise of NCBC function by N7-methyl-GTP, thus exemplifying a novel viral strategy to block host gene expression.


Asunto(s)
Transporte Activo de Núcleo Celular , COVID-19 , ARN Mensajero , SARS-CoV-2 , Proteínas no Estructurales Virales , Humanos , COVID-19/virología , Exorribonucleasas/metabolismo , Guanosina Trifosfato/metabolismo , ARN Mensajero/metabolismo , ARN Viral/genética , ARN Viral/metabolismo , SARS-CoV-2/metabolismo , Proteínas no Estructurales Virales/metabolismo
5.
Plants (Basel) ; 13(1)2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38202395

RESUMEN

Edamame is a green soybean that is rich in nutrients. Boiled edamame has been traditionally used for food in the East Asia region. It was known among farmers that conditions, such as temperature and climate on the day of harvest, affect the quality of edamame. Large-scale farmers harvest edamame on multiple days in the same year; however, the quality of edamame varies from day to day due to variations in climate conditions. In this study, we harvested edamame over several days between 2013 and 2018, obtained the climate conditions on the harvest date, and performed metabolome analysis using capillary electrophoresis mass spectrometry. To clarify the correlation between climate conditions before the harvest date and edamame components, comparative analyses of the obtained meteorological and metabolomic data were conducted. We found positive and negative correlations between the sunshine duration and average temperature, and the amounts of some edamame components. Furthermore, correlations were observed between the annual fluctuations in climate conditions and edamame components. Our findings suggest that the climate conditions before the date of harvesting are closely related to edamame quality.

6.
Plant Mol Biol ; 109(3): 249-269, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32757126

RESUMEN

KEY MESSAGE: Integrative omics approaches revealed a crosstalk among phytohormones during tuberous root development in cassava. Tuberous root formation is a complex process consisting of phase changes as well as cell division and elongation for radial growth. We performed an integrated analysis to clarify the relationships among metabolites, phytohormones, and gene transcription during tuberous root formation in cassava (Manihot esculenta Crantz). We also confirmed the effects of the auxin (AUX), cytokinin (CK), abscisic acid (ABA), jasmonic acid (JA), gibberellin (GA), brassinosteroid (BR), salicylic acid, and indole-3-acetic acid conjugated with aspartic acid on tuberous root development. An integrated analysis of metabolites and gene expression indicated the expression levels of several genes encoding enzymes involved in starch biosynthesis and sucrose metabolism are up-regulated during tuberous root development, which is consistent with the accumulation of starch, sugar phosphates, and nucleotides. An integrated analysis of phytohormones and gene transcripts revealed a relationship among AUX signaling, CK signaling, and BR signaling, with AUX, CK, and BR inducing tuberous root development. In contrast, ABA and JA inhibited tuberous root development. These phenomena might represent the differences between stem tubers (e.g., potato) and root tubers (e.g., cassava). On the basis of these results, a phytohormonal regulatory model for tuberous root development was constructed. This model may be useful for future phytohormonal studies involving cassava.


Asunto(s)
Manihot , Ácido Abscísico/metabolismo , Regulación de la Expresión Génica de las Plantas , Manihot/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/genética , Almidón/metabolismo
7.
Molecules ; 26(22)2021 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-34834100

RESUMEN

TiCl4 (or SnCl4)-promoted hetero-type benzannulation reactions using various (2,2-dichlorocyclopropyl)(thiophen-2-yl)methanols proceeded smoothly to produce uniquely substituted 4-chlorobenzothiophenes (five examples). The present approach involves the first distinctive thiophene formation from thiophene cores, in contrast to traditional methods of thiophene formation from benzene cores. The stereocongested (less reactive) Cl position in the obtained 4-chlorobenzothiophenes functioned successfully as the partners of three cross-coupling reactions: (i) a Suzuki-Miyaura cross-couplings using Pd(OAc)2/SPhos/K3PO4 catalysis (seven examples; 63-91%), (ii) a hydroxylation using KOH/Pd(dba)2/tBu-XPhos catalysis (85%), and (iii) a borylation using a B2(pin)2/Pd(dba)2/XPhos/NaOAc catalysis-provided 4-(pin)B-benzothiophene (58%).

8.
Plant Mol Biol ; 107(1-2): 63-84, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34460049

RESUMEN

KEY MESSAGE: Overexpressing Nicotinamidase 3 gene, and the exogenous application of its metabolite nicotinic acid (NA), enhance drought stress tolerance and increase biomass in Arabidopsis thaliana. With progressive global climatic changes, plant productivity is threatened severely by drought stress. Deciphering the molecular mechanisms regarding genes responsible for balancing plant growth and stress amelioration could imply multiple possibilities for future sustainable goals. Nicotinamide adenine dinucleotide (NAD) biosynthesis and recycling/ distribution is a crucial feature for plant growth. The current study focuses on the functional characterization of nicotinamidase 3 (NIC3) gene, which is involved in the biochemical conversion of nicotinamide (NAM) to nicotinic acid (NA) in the salvage pathway of NAD biosynthesis. Our data show that overexpression of NIC3 gene enhances drought stress tolerance and increases plant growth. NIC3-OX plants accumulated more NA as compared to WT plants. Moreover, the upregulation of several genes related to plant growth/stress tolerance indicates that regulating the NAD salvage pathway could significantly enhance plant growth and drought stress tolerance. The exogenous application of nicotinic acid (NA) showed a similar phenotype as the effect of overexpressing NIC3 gene. In short, we contemplated the role of NIC3 gene and NA application in drought stress tolerance and plant growth. Our results would be helpful in engineering plants with enhanced drought stress tolerance and increased growth potential.


Asunto(s)
Adaptación Fisiológica/genética , Proteínas de Arabidopsis/genética , Arabidopsis/fisiología , Sequías , Regulación de la Expresión Génica de las Plantas , Niacina/fisiología , Nicotinamidasa/genética , Adaptación Fisiológica/efectos de los fármacos , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Genes de Plantas , Modelos Biológicos , NAD/metabolismo , NADP/metabolismo , Niacina/farmacología , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Raíces de Plantas/fisiología , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/genética , Brotes de la Planta/fisiología , Plantas Modificadas Genéticamente , Estrés Fisiológico/efectos de los fármacos , Estrés Fisiológico/genética , Transcriptoma/genética , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/genética
9.
Front Plant Sci ; 12: 687799, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34220909

RESUMEN

Durian is an economically important fruit of Southeast Asia. There is, however, a lack of in-depth information on the alteration of its metabolic networks during ripening. Here, we annotated 94 ripening-associated metabolites from the pulp of durian cv. Monthong fruit at unripe and ripe stages, using capillary electrophoresis- and gas chromatography- time-of-flight mass spectrometry, specifically focusing on taste-related metabolites. During ripening, sucrose content increased. Change in raffinose-family oligosaccharides are reported herein for the first time. The malate and succinate contents increased, while those of citrate, an abundant organic acid, were unchanged. Notably, most amino acids increased, including isoleucine, leucine, and valine, whereas aspartate decreased, and glutamate was unchanged. Furthermore, transcriptomic analysis was performed to analyze the dynamic changes in sugar metabolism, glycolysis, TCA cycle, and amino acid pathways to identify key candidate genes. Taken together, our results elucidate the fundamental taste-related metabolism of durian, which can be exploited to develop durian metabolic and genetic markers in the future.

10.
ACS Omega ; 6(28): 18135-18156, 2021 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-34308046

RESUMEN

A distinctive method for synthesizing a variety of multisubstituted α-arylnaphthalenes utilizing novel regiocontrolled ipso-type [4 + 2] benzannulation is presented. Ortho- and para-substituted 1-Ar1-1-Ar2-2,2-dichlorocyclopropylmethanols (AACM) were transformed to the corresponding ipso-type α-arylnaphthalenes. (i) The reaction of ortho-AACM using TiCl4 or SnCl4 (1.0 equiv) proceeded smoothly to afford ipso-type α-arylnaphthalenes (seven examples; 49-69% yield) exclusively, without producing conventional benzannulation isomers. (ii) Para-AACM also underwent the reaction successfully to afford the desired ipso-type α-arylnaphthalenes (14 examples; 39-98% yield) without producing conventional benzannulation isomers. (iii) In contrast, meta-AACM underwent the previously reported conventional benzannulation. (iv) The present method exhibited sufficient substrate generality for application to ortho- and para-substituted AACM substrates bearing Me-, Cl-, and MeO- groups. (v) The six key structures were unambiguously confirmed by X-ray structure analyses. (vi) A plausible reaction mechanism for the present ipso-type reaction is proposed and supported by three careful cross-over and comparable experiments. To demonstrate the utility of the present reaction, we achieved the first total synthesis of chaihunaphthone, a uniquely (highly congested) substituted and less accessible natural lignan lactone with three contiguous trimethoxy substituents (total eight steps, overall 6.4% yield).

11.
Gene ; 787: 145647, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-33845136

RESUMEN

RecQ4, a member of the RecQ helicase family, is required for the maintenance of genome integrity. RecQ4 has been shown to promote the following two DNA double-strand break (DSB) repair pathways: non-homologous end joining (NHEJ) and homologous recombination (HR). However, its molecular function has not been fully elucidated. In the present study, we aimed to investigate the role of RecQ4 in NHEJ using Xenopus egg extracts. The N-terminal 598 amino acid region of Xenopus RecQ4 (N598), which lacks a central helicase domain and a downstream C-terminal region, was added to the extracts and its effect on the joining of DNA ends was analyzed. We found that N598 inhibited the joining of linearized DNA ends in the extracts. In addition, N598 inhibited DSB-induced chromatin binding of Ku70, which is essential for NHEJ, while the DSB-induced chromatin binding of the HR-associated proteins, replication protein A (RPA) and Rad51, increased upon the addition of N598. These results suggest that RecQ4 possibly influences the choice of the DSB repair pathway by influencing the association of the Ku heterodimer with the DNA ends.


Asunto(s)
Reparación del ADN por Unión de Extremidades , Autoantígeno Ku/metabolismo , RecQ Helicasas/metabolismo , Proteínas de Xenopus/fisiología , Animales , Cromatina , ADN/metabolismo , Autoantígeno Ku/antagonistas & inhibidores , Unión Proteica , RecQ Helicasas/genética , Xenopus laevis
12.
J Exp Bot ; 72(7): 2570-2583, 2021 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-33481019

RESUMEN

Understanding the limiting factors of grain filling is essential for the further improvement of grain yields in rice (Oryza sativa). The relatively slow grain growth of the high-yielding cultivar 'Momiroman' is not improved by increasing carbon supply, and hence low sink activity (i.e. the metabolic activity of assimilate consumption/storage in sink organs) may be a limiting factor for grain filling. However, there is no metabolic evidence to corroborate this hypothesis, partly because there is no consensus on how to define and quantify sink activity. In this study, we investigated the carbon flow at a metabolite level from photosynthesis in leaves to starch synthesis in grains of three high-yielding cultivars using the stable isotope 13C. We found that a large amount of newly fixed carbon assimilates in Momiroman was stored as hexose instead of being converted to starch. In addition, the activity of ADP-glucose pyrophosphorylase and the expression of AGPS2b, which encodes a subunit of the ADP-glucose pyrophosphorylase enzyme, were both lower in Momiroman than in the other two cultivars in grains in superior positions on panicle branches. Hence, slower starch synthesis from hexose, which is partly explained by the low expression level of AGPS2b, may be the primary metabolic reason for the lower sink activity observed in Momiroman.


Asunto(s)
Oryza , Almidón/biosíntesis , Carbono , Hexosas , Oryza/metabolismo , Proteínas de Plantas/metabolismo
13.
Microscopy (Oxf) ; 70(2): 250-254, 2021 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-32901813

RESUMEN

Microstructural changes during the martensitic transformation from face-centred cubic (FCC) to body-centred cubic (BCC) in an Fe-31Ni alloy were observed by scanning electron microscopy (SEM) with a newly developed Peltier stage available at temperatures to -75°C. Electron channelling contrast imaging (ECCI) was utilized for the in situ observation during cooling. Electron backscatter diffraction analysis at ambient temperature (20°C) after the transformation was performed for the crystallographic characterization. A uniform dislocation slip in the FCC matrix associated with the transformation was detected at -57°C. Gradual growth of a BCC martensite was recognized upon cooling from -57°C to -63°C.

14.
Surg Case Rep ; 6(1): 75, 2020 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-32307602

RESUMEN

BACKGROUND: Trousseau's syndrome is a cancer-associated thrombosis. Trousseau's syndrome with cholangiocarcinoma is a rare condition with poor prognosis. CASE PRESENTATION: A 59-year-old female was admitted to our hospital with abdominal pain, headache, and nausea. Abdominal enhanced computed tomography revealed liver tumor, splenic infarction, and bilateral renal infarction. Multiple acute cerebral infarctions were also detected by magnetic resonance imaging. Her preoperative serum levels of carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) were > 120,000 U/mL and 589.6 ng/mL, respectively, which were extremely high. Histopathology after right hepatectomy revealed moderately differentiated adenocarcinoma consistent with intrahepatic cholangiocarcinoma. Her serum levels of CA19-9 were trending down to 9029.2 and 2659.8 U/mL at 1 and 3 weeks after surgery, respectively. However, at 7 weeks after surgery, her CA19-9 levels increased in the presence of positive imaging findings in the remnant liver, hilar lymph nodes, and peritoneal cavity. The initiation of combination chemotherapy including gemcitabine and cisplatin had a significant effect. The patient was doing well at 6 months after the surgery. CONCLUSION: This rare case of Trousseau's syndrome due to cholangiocarcinoma suggests that extremely high CA19-9 levels might be a pathogenic factor of this syndrome.

15.
Biochem Biophys Res Commun ; 524(1): 83-88, 2020 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-31980164

RESUMEN

Phenylacetic acid (PAA) is one type of natural auxin and widely exists in plants. Previous biochemical studies demonstrate that PAA in plants is synthesized from phenylalanine (Phe) via phenylpyruvate (PPA), but the PAA biosynthetic genes and its regulation remain unknown. In this article, we show that the AROGENATE DEHYDRATASE (ADT) family, which catalyzes the conversion of arogenate to Phe, can modulate the levels of PAA in Arabidopsis. We found that overexpression of ADT4 or ADT5 remarkably increased the amounts of PAA. Due to an increase in PAA levels, ADT4ox and ADT5ox plants can partially restore the auxin-deficient phenotypes caused by treatments with an inhibitor of the biosynthesis of indole-3-acetic acid (IAA), a main auxin in plants. In contrast, the levels of PAA were significantly reduced in adt multiple knockout mutants. Moreover, the levels of PPA are substantially increased in ADT4 or ADT5 overexpression plants but reduced in adt multiple knockout mutants, suggesting that PPA is a key intermediate of PAA biosynthesis. These results provide an evidence that members of the ADT family of Arabidopsis can modulate PAA level via the PPA-dependent pathway.


Asunto(s)
Arabidopsis/genética , Arabidopsis/metabolismo , Hidroliasas/genética , Hidroliasas/metabolismo , Fenilacetatos/metabolismo , Aminoácidos Dicarboxílicos/metabolismo , Ciclohexenos/metabolismo , Regulación de la Expresión Génica de las Plantas , Técnicas de Silenciamiento del Gen , Ácidos Indolacéticos/metabolismo , Mutación , Fenilalanina/metabolismo , Plantas Modificadas Genéticamente , Tirosina/análogos & derivados , Tirosina/metabolismo
16.
Food Chem ; 268: 118-125, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-30064738

RESUMEN

Durian (Durio zibethinus M.) is a major economic fruit crop in Thailand. In this study, two popular cultivars, namely Chanee and Mon Thong, were collected from three orchards located in eastern Thailand. The pulp metabolome, including 157 annotated metabolites, was explored using capillary electrophoresis-time of flight/mass spectrometry (CE-TOF/MS). Cultivars and harvest years had more impact on metabolite profile separation than cultivation areas. We identified cultivar-dependent metabolite markers related to durian fruit quality traits, such as nutritional value (pyridoxamine), odor (cysteine, leucine), and ripening process (aminocyclopropane carboxylic acid). Interestingly, durian fruit were found to contain high amounts of γ-glutamylcysteine (810.3 ±â€¯257.5 mg/100 g dry weight) and glutathione (158.1 ±â€¯80.4 mg/100 g dry weight), which act as antioxidants and taste enhancers. This metabolite information could be related to consumer preferences and exploited for durian fruit quality improvement.


Asunto(s)
Bombacaceae/metabolismo , Frutas , Metabolómica , Gusto , Aromatizantes , Tailandia
17.
Dev Biol ; 442(1): 40-52, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30026120

RESUMEN

Plants often display a high competence for regeneration under stress conditions. Signals produced in response to various types of stress serve as critical triggers for de novo organogenesis, but the identity of these signaling molecules underlying cellular reprogramming are largely unknown. We previously identified an AP2/ERF transcription factor, WOUND INDUCED DEDIFFERENTIATION1 (WIND1), as a key regulator involved in wound-induced cellular reprogramming in Arabidopsis. In this study, we found that activation of Arabidopsis WIND1 (AtWIND1) in hypocotyl explants of Brassica napus (B. napus) enhances callus formation and subsequent organ regeneration. Gene expression analyses revealed that AtWIND1 enhances expression of B. napus homologs of ENHANCER OF SHOOT REGENERATION1/DORNRÖSCHEN (ESR1/DRN), which is a direct target of WIND1 in Arabidopsis. Further, time-course hormonal analyses showed that an altered balance of endogenous auxin/cytokinin exists in AtWIND1-activated B. napus explants. Our mass spectrometry analyses, in addition, uncovered dynamic metabolomic reprogramming in AtWIND1-activated explants, including accumulation of several compounds, e.g. proline, gamma aminobutyric acid (GABA), and putrescine, that have historically been utilized as additives to enhance plant cell reprogramming in tissue culture. Our findings thus provide new insights into how WIND1 functions to promote cell reprogramming.


Asunto(s)
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/fisiología , Brassica napus/genética , Factores de Transcripción/genética , Factores de Transcripción/fisiología , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Reprogramación Celular/genética , Reprogramación Celular/fisiología , Citocininas/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/genética , Genes de Plantas , Ácidos Indolacéticos/metabolismo , Organogénesis de las Plantas/genética , Brotes de la Planta/metabolismo , Plantas Modificadas Genéticamente , Prolina , Putrescina , Regeneración/genética , Factores de Transcripción/metabolismo , Ácido gamma-Aminobutírico
18.
Plant Cell Physiol ; 59(7): 1353-1362, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29660082

RESUMEN

We analyzed the metabolites and proteins contained in pure intact vacuoles isolated from Arabidopsis suspension-cultured cells using capillary electrophoresis-mass spectrometry (CE-MS), Fourier transform-ion cyclotron resonance (FT-ICR)-MS and liquid chromatography (LC)-MS. We identified 21 amino acids and five organic acids as major primary metabolites in the vacuoles with CE-MS. Further, we identified small amounts of 27 substances including well-known vacuolar molecules, but also some unexpected substances (e.g. organic phosphate compounds). Non-target analysis of the vacuolar sample with FT-ICR-MS suggested that there are 1,106 m/z peaks that could predict the 5,090 molecular formulae, and we have annotated 34 compounds in these peaks using the KNapSAck database. By conducting proteomic analysis of vacuolar sap, we found 186 proteins in the same vacuole samples. Since the vacuole is known as a major degradative compartment, many of these were hydrolases, but we also found various oxidoreductases and transferases. The relationships between the proteins and metabolites in the vacuole are discussed.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Vacuolas/metabolismo , Aminoácidos/metabolismo , Arabidopsis/citología , Proteínas de Arabidopsis/análisis , Técnicas de Cultivo de Célula/métodos , Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Monoéster Fosfórico Hidrolasas/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier/métodos
19.
Chirality ; 30(6): 816-827, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29659053

RESUMEN

Accessible chiral syntheses of 3 types of (R)-2-sulfanylcarboxylic esters and acids were performed: (R)-2-sulfanylpropanoic (thiolactic) ester (53%, 98%ee) and acid (39%, 96%ee), (R)-2-sulfanylsucciinic diester (59%, 96%ee), and (R)-2-mandelic ester (78%, 90%ee) and acid (59%, 96%ee). The present practical and robust method involves (i) clean SN 2 displacement of methanesulfonates of (S)-2-hydroxyesters by using commercially available AcSK with tris(2-[2-methoxyethoxy])ethylamine and (ii) sufficiently mild deacetylation. The optical purity was determined by the corresponding (2R,5R)-trans-thiazolidin-4-one and (2S,5R)-cis-thiazolidin-4-one derivatives based on accurate high-performance liquid chromatography analysis with high-resolution efficiency. Compared with the reported method utilizing AcSCs (generated from AcSH and CsCO3 ), the present method has several advantages, that is, the use of odorless AcCOSK reagent, reasonable reaction velocity, isolation procedure, and accurate, reliable optical purity determination. The use of accessible AcSK has advantages because of easy-to-handle odorless and hygroscopic solid that can be used in a bench-top procedure. The Ti(OiPr)4 catalyst promoted smooth trans-cyclo-condensation to afford (2R,5R)-trans-thiazolidin-4-one formation of (R)-2-sulfanylcarboxylic esters with available N-(benzylidene)methylamine under neutral conditions without any racemization, whereas (2S,5R)-cis-thiazollidin-4-ones were obtained via cis-cyclo-condensation and no catalysts. Direct high-performance liquid chromatography analysis of methyl (R)-mandelate was also performed; however, the resolution efficiency was inferior to that of the thaizolidin-4-one derivatizations.

20.
Chemosphere ; 188: 444-454, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28892774

RESUMEN

Predicting the fates of arsenic (As) and selenium (Se) in natural geologic media like rocks and soils necessitates the understanding of how their various oxyanionic species behave and migrate under dynamic conditions. In this study, geochemical factors and processes crucial in the leaching and transport of arsenite (AsIII), arsenate (AsV), selenite (SeIV) and selenate (SeVI) in tunnel-excavated rocks of marine origin were investigated using microscopic/extraction techniques, column experiments, dissolution-precipitation kinetics and one-dimensional reactive transport modeling. The results showed that evaporite salts were important because aside from containing As and Se, they played crucial roles in the evolution of pH and concentrations of coexisting ions, both of which had strong effects on adsorption-desorption reactions of As and Se species with iron oxyhydroxide minerals/phases. The observed leaching trends of AsV, AsIII, SeIV and SeVI were satisfactorily simulated by one-dimensional reactive transport models, which predict that preferential adsorptions of AsV and SeIV were magnified by geochemical changes in the columns due to water flow. Moreover, our results showed that migrations of AsIII, SeIV and SeVI could be predicted adequately by 1D solute transport with simple activity-K'd approach, but surface complexation was more reliable to simulate adsorption-desorption behavior of AsV.


Asunto(s)
Arsenicales/análisis , Sedimentos Geológicos/química , Minerales/química , Modelos Químicos , Compuestos de Selenio/análisis , Contaminantes Químicos del Agua/análisis , Adsorción , Arsenicales/química , Cinética , Oxidación-Reducción , Compuestos de Selenio/química , Solubilidad , Movimientos del Agua , Contaminantes Químicos del Agua/química
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