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l-tryptophan

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https://www.readbyqxmd.com/read/28419111/time-resolved-and-label-free-monitoring-of-extracellular-metabolites-by-surface-enhanced-raman-spectroscopy
#1
Victoria Shalabaeva, Laura Lovato, Rosanna La Rocca, Gabriele C Messina, Michele Dipalo, Ermanno Miele, Michela Perrone, Francesco Gentile, Francesco De Angelis
Metabolomics is an emerging field of cell biology that aims at the comprehensive identification of metabolite levels in biological fluids or cells in a specific functional state. Currently, the major tools for determining metabolite concentrations are mass spectrometry coupled with chromatographic techniques and nuclear magnetic resonance, which are expensive, time consuming and destructive for the samples. Here, we report a time resolved approach to monitor metabolite dynamics in cell cultures, based on Surface Enhanced Raman Scattering (SERS)...
2017: PloS One
https://www.readbyqxmd.com/read/28417340/preconditioning-of-primary-human-renal-proximal-tubular-epithelial-cells-without-tryptophan-increases-survival-under-hypoxia-by-inducing-autophagy
#2
Theodoros Eleftheriadis, Georgios Pissas, Maria Sounidaki, Nikolaos Antoniadis, Georgia Antoniadi, Vassilios Liakopoulos, Ioannis Stefanidis
PURPOSE: Hypoxia plays a significant role in the pathogenesis of acute kidney injury (AKI). Autophagy protects from AKI. Amino acid deprivation induces autophagy. The effect of L-tryptophan depletion on survival and autophagy in cultures of renal proximal tubular epithelial cells (RPTECs) under hypoxia was evaluated. METHODS: RPTECs were preconditioned in a medium containing or not tryptophan, following culture under hypoxia and treatment with or without the autophagy inhibitor chloroquine...
April 17, 2017: International Urology and Nephrology
https://www.readbyqxmd.com/read/28416218/dummy-molecularly-imprinted-microbeads-as-solid-phase-extraction-material-for-selective-determination-of-phthalate-esters-in-water
#3
Elif Tümay Özer, Bilgen Osman, Tuğçe Yazıcı
The aim of this study was to investigate the usability of newly synthesized dummy molecularly imprinted microbeads (DMIMs) as a solid phase extraction (SPE) material to determine six phthalate esters (PEs) in water by GC-MS analysis. Diethyl phthalate (DEP) was used as a dummy template to prepare poly(ethylene glycol dimethacrylate N-methacryloyl-l-tryptophan methyl ester) [PEMATrp)] DMIMs by using suspension polymerization. The PEMATrp DMIMs were characterized by using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM)...
April 9, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28398659/hypaphorine-an-indole-alkaloid-isolated-from-caragana-korshinskii-kom-inhibites-3t3-l1-adipocyte-differentiation-and-improves-insulin-sensitivity-in-vitro
#4
Guangxiang Luan, Fangfang Tie, Zhenzhen Yuan, Gang Li, Jie He, Zhenhua Wang, Honglun Wang
Obesity, a major health problem worldwide, is a complex multifactorial chronic disease that increases the risk for insulin resistance, type 2 diabetes, coronary heart disease and hypertension. In this study, we assessed methods to isolate hypaphorine, a potent drug candidate for obesity and insulin resistance. Semi-preparative reversed-phase liquid chromatography (semi-preparative RPLC) was established as a method to separate three compounds, adenosine, L-tryptophan and hypaphorine, from the crude extracts of Caragana korshinskii Kom...
April 11, 2017: Chemistry & Biodiversity
https://www.readbyqxmd.com/read/28397062/multi-metal-resistance-and-plant-growth-promotion-potential-of-a-wastewater-bacterium-pseudomonas-aeruginosa-and-its-synergistic-benefits
#5
Jayanta Kumar Biswas, Monojit Mondal, Jörg Rinklebe, Santosh Kumar Sarkar, Punarbasu Chaudhuri, Mahendra Rai, Sabry M Shaheen, Hocheol Song, Muhammad Rizwan
Water and soil pollution by toxic heavy metals (HMs) is increasing globally because of increase in population, industrialization and urbanization. It is a burning problem for the public, scientists, academicians and politicians how to tackle the toxic contaminants which jeopardize the environment. One possible solution for pollution abatement is a bioremediation-effective and innovative technology that uses biological systems for treatment of contaminants. Many bacteria synthesize indole-3-acetic acid (IAA) which is a product of L-tryptophan metabolism and belongs to the auxin class of plant growth-promoting hormone...
April 10, 2017: Environmental Geochemistry and Health
https://www.readbyqxmd.com/read/28388167/collective-hydration-dynamics-in-some-amino-acid-solutions-a-combined-ghz-thz-spectroscopic-study
#6
Nirnay Samanta, Debasish Das Mahanta, Samiran Choudhury, Anjan Barman, Rajib Kumar Mitra
A detailed understanding of hydration of amino acids, the building units of protein, is a key step to realize the overall solvation processes in proteins. In the present contribution, we have made a combined GHz (0.2-50) to THz (0.3-2.0) experimental spectroscopic study to investigate the dynamics of water at room temperature in the presence of different amino acids (glycine, L-serine, L-lysine, L-tryptophan, L-arginine, and L-aspartic acid). The THz absorption coefficient, α(ν), of amino acids follows a trend defined by their solvent accessible surface area...
March 28, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28362260/evolution-of-substrate-specificity-in-a-retained-enzyme-driven-by-gene-loss
#7
Ana Lilia Juárez-Vázquez, Janaka E Edirisinghe, Ernesto A Verduzco-Castro, Karolina Michalska, Chenggang Wu, Lianet Noda-García, Gyorgy Babnigg, Michael Endres, Sofía Medina-Ruíz, Julián Santoyo-Flores, Mauricio Carrillo-Tripp, Hung Ton-That, Andrzej Joachimiak, Christopher S Henry, Francisco Barona-Gómez
The connection between gene loss and the functional adaptation of retained proteins is still poorly understood. We apply phylogenomics and metabolic modeling to detect bacterial species that are evolving by gene loss, with the finding that Actinomycetaceae genomes from human cavities are undergoing sizable reductions, including loss of L-histidine and L-tryptophan biosynthesis. We observe that the dual-substrate phosphoribosyl isomerase A or priA gene, at which these pathways converge, appears to coevolve with the occurrence of trp and his genes...
March 31, 2017: ELife
https://www.readbyqxmd.com/read/28357780/targeting-tdo-in-cancer-immunotherapy
#8
REVIEW
Cheng-Peng Yu, Yun-Lei Song, Zheng-Ming Zhu, Bo Huang, Ying-Qun Xiao, Da-Ya Luo
Tryptophan-2,3-dioxygenase (TDO) is a homotetrameric heme-containing protein catalyzing the initial step in the kynurenine pathway, which oxidates the 2,3-double bond of the indole ring in L-tryptophan and catalyzes it into kynurenine (KYN). The upregulation of TDO results in a decrease in tryptophan and the accumulation of KYN and its metabolites. These metabolites can affect the proliferation of T cells. Increasing evidence demonstrates that TDO is a promising therapeutic target in the anti-tumor process...
May 2017: Medical Oncology
https://www.readbyqxmd.com/read/28353092/functional-and-phylogenetic-diversity-of-cultivable-rhizobacterial-endophytes-of-sorghum-sorghum-bicolor-l-moench
#9
Venkadasamy Govindasamy, Susheel Kumar Raina, Priya George, Mahesh Kumar, Jagadish Rane, Paramjit Singh Minhas, Kanuparthy Pandu Ranga Vittal
A diverse group of bacteria colonize the exo- and endo-rhizospheres of sorghum and play a critical role in its tolerance to drought and other abiotic stresses. Two hundred and eighty endophytic bacteria were isolated from the surface-sterilized roots of four sorghum cultivars that were grown on three soil types at three different phenological stages of growth. The isolates were subjected to in vitro screening for their plant growth promoting traits. Out of 280 isolates, 70 could produce Indole 3-Acetic Acid (IAA), 28 showed N-fixation, 28 could solubilize phosphate, 24 had ACC deaminase activity and 13 isolates were able to produce siderophores...
March 28, 2017: Antonie Van Leeuwenhoek
https://www.readbyqxmd.com/read/28343381/rerouting-the-pathway-for-the-biosynthesis-of-the-side-ring-system-of-nosiheptide-the-roles-of-nosi-nosj-and-nosk
#10
Edward Badding, Tyler L Grove, Lauren Gadsby, Joseph LaMattina, Amie K Boal, Squire J Booker
Nosiheptide (NOS) is a highly modified thiopeptide antibiotic that displays formidable in vitro activity against a variety of Gram-positive bacteria. In addition to a central hydroxypyridine ring, NOS contains several other modifications, including multiple thiazole rings, dehydro-amino acids, and a 2,4-dimethylindolic acid (DMIA) moiety, among others. The DMIA moiety is required for NOS efficacy and is synthesized from L-tryptophan in a series of reactions that have not been fully elucidated. Herein, we describe the role of NosJ-the product of an unannotated gene in the biosynthetic operon for NOS-as an acyl carrier protein that delivers 2-methylindolic acid (MIA) to NosK...
March 27, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28318003/small-molecule-hedgehog-pathway-antagonists
#11
Trieu N Trinh, Eileen A McLaughlin, Christopher P Gordon, Ilana R Bernstein, Victoria J Pye, Kate A Redgrove, Adam McCluskey
Leveraging our quinolone-1-(2H)-one based Hedgehog signalling pathway (HSP) inhibitors we have developed two new classes of HSP inhibitors based on: l-tryptophan and benzo[1,3]dioxol-5-ylmethyl-[2-(1H-indol-3-yl)-ethyl]-amine. Synthesis of focused compound libraries identified six l-tryptophan based inhibitors, and two stimulators, of Gli at 10 μM compound concentration. 2,4-Dichloro-13 and indole 16 suppressed mRNA expression of Ptch1 in Shh LIGHT2 cells, with 13 suppressing and 16 stimulating Gli2 mRNA expression...
March 20, 2017: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/28302759/preclinical-evaluation-of-11-c-sarcosine-as-a-substrate-of-proton-coupled-amino-acid-transporters-and-first-human-application-in-prostate-cancer
#12
Morand Piert, Xia Shao, David M Raffel, Mathew S Davenport, Jeffrey Montgomery, Lakshmi Kunju, Brian G Hockley, Javed Siddiqui, Peter J H Scott, Arul Chinnaiyan, Thekkelnaycke Rajandiran
Sarcosine is a known substrate of proton-coupled amino acid transporters (PAT), which are overexpressed in selected tissues and solid tumors. Sarcosine, an N-methyl derivative of the amino acid glycine and a metabolic product of choline, plays an important role for prostate cancer aggressiveness and progression. Methods: Carbon-11 radiolabeled sarcosine ((11)C-sarcosine) was tested as a new positron emission tomography (PET) imaging probe in comparison with (11)C-choline in two prostate cancer tumor xenograft models (DU-145 and PC-3)...
March 16, 2017: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
https://www.readbyqxmd.com/read/28298987/effect-of-different-concentrations-of-specific-inhibitor-of-matrix-metalloproteinases-on-the-shear-bond-strength-of-self-adhesive-resin-cements-to-dentin
#13
Mohammad-Esmaeel Ebrahimi-Chaharom, Mehdi Abed-Kahnamoui, Mahmoud Bahari, Hamed Hamishehkar, Mahya Gharouni
BACKGROUND: Considering the probability of chemical and enzymatic reactions between matrix metalloproteinases (MMPs) in the dentin structure and their specific inhibitors, the aim of the present study was to evaluate the effect of different concentrations of specific inhibitor of MMPs (galardin) on the shear bond strength of self-adhesive resin cements to dentin. MATERIAL AND METHODS: Forty-eight sound human premolars were mounted in self-cured acrylic resin after removal of the enamel on the buccal and lingual surfaces...
March 2017: Journal of Clinical and Experimental Dentistry
https://www.readbyqxmd.com/read/28286019/methotrexate-causes-acute-hyperplasia-of-enterochromaffin-cells-containing-substance-p-in-the-intestinal-mucosa-of-rats
#14
Takuji Machida, Yuho Takano, Kenji Iizuka, Maiko Machida, Masahiko Hirafuji
This study aimed to investigate the acute and chronic effect of methotrexate on the intestinal substance P metabolism after a single administration to rats. Methotrexate caused a significant increase in the number of substance P-containing cells in the ileal mucosa both at 24 and 96 h. Most of enterochromaffin cells expressing l-tryptophan hydroxylase contained substance P. The expression of Tac1 mRNA was increased by methotrexate at 24 h, but not at 96 h. Thus, methotrexate causes acute hyperplasia of enterochromaffin cells in the intestinal mucosa of rats with a transient increase in the production of substance P...
February 22, 2017: Journal of Pharmacological Sciences
https://www.readbyqxmd.com/read/28283907/nanoparticles-generated-from-a-tryptophan-derivative-physical-characterization-and-anti-cancer-drug-delivery
#15
Taru Dube, Saurabh Mandal, Jiban Jyoti Panda
Surging reports of peptide-based nanosystems and their growing potency in terms of biological utility demand for the search of newer and simpler peptide-based systems that could serve as smart templates for the development of self-assembled nanostructures. Use of simple amino acids as monomeric building blocks for synthesizing ensembles of nanostructures have gained momentum in this direction with some reports focusing on the development of nanosystems from single or modified single amino acids. In this work, we have demonstrated self-assembly and nanoparticle formation ability of a single amino acid derivative, N-alpha-(9-fluorenylmethyloxycarbonyl)-N(in)-tert-butyloxycarbonyl-L-tryptophan [Fmoc-Trp(Boc)-OH]...
March 10, 2017: Amino Acids
https://www.readbyqxmd.com/read/28275295/investigation-of-mitigating-effect-of-colon-specific-prodrugs-of-boswellic-acid-on-2-4-6-trinitrobenzene-sulfonic-acid-induced-colitis-in-wistar-rats-design-kinetics-and-biological-evaluation
#16
Ajinkya Sarkate, Suneela S Dhaneshwar
AIM: To develop a colon-targeting bioreversible delivery system for β-boswellic acid (BBA) and explore utility of its prodrugs in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. METHODS: Synthesis of 4 co-drugs of BBA with essential amino acids was achieved by CDI coupling, followed by their spectral characterization. In vitro kinetics were studied by HPLC in aqueous buffers, homogenates of gastrointestinal tract and fecal matter. In vivo kinetic studies were performed in Wistar rat plasma, urine and feces...
February 21, 2017: World Journal of Gastroenterology: WJG
https://www.readbyqxmd.com/read/28268250/antioxidant-effect-of-thiazolidine-molecules-in-cell-culture-media-improves-stability-and-performance
#17
Jennifer Kuschelewski, Alisa Schnellbaecher, Sascha Pering, Maria Wehsling, Aline Zimmer
The ability of cell culture media components to generate reactive species as well as their sensitivity to oxidative degradation, affects the overall stability of media and the behavior of cells cultured in vitro. This study investigates the influence of thiazolidine molecules, formed from the condensation between cysteine and alpha-ketoacids, on the stability of these complex mixtures and on the performance of cell culture processes aiming to produce therapeutically relevant monoclonal antibodies. Results presented in this study indicate that 2-methyl-1,3-thiazolidine-2,4-dicarboxylic acid and 2-(2-carboxyethyl)-1,3-thiazolidine-2,4-dicarboxylic acid, obtained by condensation of cysteine with pyruvate or alpha-ketoglutarate respectively, are able to stabilize cell culture media formulations, in particular redox sensitive molecules like folic acid, thiamine, L-methionine (met) and L-tryptophan (trp)...
March 7, 2017: Biotechnology Progress
https://www.readbyqxmd.com/read/28214225/a-relay-pathway-between-arginine-and-tryptophan-metabolism-confers-immunosuppressive-properties-on-dendritic-cells
#18
Giada Mondanelli, Roberta Bianchi, Maria Teresa Pallotta, Ciriana Orabona, Elisa Albini, Alberta Iacono, Maria Laura Belladonna, Carmine Vacca, Francesca Fallarino, Antonio Macchiarulo, Stefano Ugel, Vincenzo Bronte, Federica Gevi, Lello Zolla, Auke Verhaar, Maikel Peppelenbosch, Emilia Maria Cristina Mazza, Silvio Bicciato, Yasmina Laouar, Laura Santambrogio, Paolo Puccetti, Claudia Volpi, Ursula Grohmann
Arginase 1 (Arg1) and indoleamine 2,3-dioxygenase 1 (IDO1) are immunoregulatory enzymes catalyzing the degradation of l-arginine and l-tryptophan, respectively, resulting in local amino acid deprivation. In addition, unlike Arg1, IDO1 is also endowed with non-enzymatic signaling activity in dendritic cells (DCs). Despite considerable knowledge of their individual biology, no integrated functions of Arg1 and IDO1 have been reported yet. We found that IDO1 phosphorylation and consequent activation of IDO1 signaling in DCs was strictly dependent on prior expression of Arg1 and Arg1-dependent production of polyamines...
February 21, 2017: Immunity
https://www.readbyqxmd.com/read/28211258/effects-of-a-wide-range-of-dietary-nicotinamide-riboside-nr-concentrations-on-metabolic-flexibility-and-white-adipose-tissue-wat-of-mice-fed-a-mildly-obesogenic-diet
#19
Wenbiao Shi, Maria A Hegeman, Dorien A M van Dartel, Jing Tang, Manuel Suarez, Hans Swarts, Bart van der Hee, Lluis Arola, Jaap Keijer
SCOPE: Metabolic flexibility is the ability to switch metabolism between carbohydrate oxidation (CHO) and fatty acid oxidation (FAO) and is a biomarker for metabolic health. The effect on metabolic health of nicotinamide riboside (NR) as an exclusive source of vitamin B3 is unknown and is examined here for a wide range of NR. DESIGN AND METHODS: Nine-week-old male C57BL/6JRcc mice received a semi-purified mildly obesogenic (40 en% fat) diet containing 0.14% L-tryptophan and either 5, 15, 30, 180, or 900 mg NR per kg diet for 15 weeks...
February 16, 2017: Molecular Nutrition & Food Research
https://www.readbyqxmd.com/read/28195396/development-of-a-validated-strategy-for-the-determination-of-tryptamine-in-human-cerebrospinal-fluid-in-the-presence-of-competitors-using-molecularly-imprinted-polymers
#20
Piotr Luliński, Magdalena Bamburowicz-Klimkowska, Mariusz Dana, Dorota Maciejewska
This study presents a validated strategy for the determination of tryptamine in the presence of its competitors, which involves the molecularly imprinted solid-phase extraction combined with high-performance liquid chromatography coupled with fluorimetric detection. Tryptamine-imprinted microscale sorbent was produced from 4-vinylbenzoic acid and ethylene glycol dimethacrylate in methanol by precipitation polymerization, and its imprinting factor was equal to 15.4 in static experiments or 18.6 in dynamic binding experiments...
April 2017: Journal of Separation Science
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