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L-methyl tryptophan

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https://www.readbyqxmd.com/read/28416218/dummy-molecularly-imprinted-microbeads-as-solid-phase-extraction-material-for-selective-determination-of-phthalate-esters-in-water
#1
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/28344890/suppression-of-indoleamine-2-3-dioxygenase-1-expression-by-promoter-hypermethylation-in-er-positive-breast-cancer
#2
Dyah L Dewi, Soumya R Mohapatra, Saioa Blanco Cabañes, Isabell Adam, Luis F Somarribas Patterson, Bianca Berdel, Masroor Kahloon, Loreen Thürmann, Stefanie Loth, Katharina Heilmann, Dieter Weichenhan, Oliver Mücke, Ines Heiland, Pauline Wimberger, Jan Dominik Kuhlmann, Karl-Heinz Kellner, Sarah Schott, Christoph Plass, Michael Platten, Clarissa Gerhäuser, Saskia Trump, Christiane A Opitz
Kynurenine formation by tryptophan-catabolic indoleamine-2,3-dioxygenase 1 (IDO1) plays a key role in tumor immune evasion and inhibition of IDO1 is efficacious in preclinical models of breast cancer. As the response of breast cancer to immune checkpoint inhibitors may be limited, a better understanding of the expression of additional targetable immunomodulatory pathways is of importance. We therefore investigated the regulation of IDO1 expression in different breast cancer subtypes. We identified estrogen receptor α (ER) as a negative regulator of IDO1 expression...
2017: Oncoimmunology
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
#3
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/28268250/antioxidant-effect-of-thiazolidine-molecules-in-cell-culture-media-improves-stability-and-performance
#4
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/28221769/manipulation-of-the-precursor-supply-in-yeast-significantly-enhances-the-accumulation-of-prenylated-%C3%AE-carbolines
#5
Katja Backhaus, Lena Ludwig-Radtke, Xiulan Xie, Shu-Ming Li
The tryptophan derivative 1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (MTCA) is present in many plants and foods including fermentation products of the baker's yeast Saccharomyces cerevisiae. MTCA is formed from tryptophan and acetaldehyde via a Pictet-Spengler reaction. In this study, up to 9 mg/L of MTCA were detected as a mixture of (1S,3S) and (1R,3S) isomers in a ratio of 2.2:1 in Saccharomyces cerevisiae cultures. To the best of our knowledge, this is the first report on the presence of MTCA in laboratory baker's yeast cultures...
March 2, 2017: ACS Synthetic Biology
https://www.readbyqxmd.com/read/28208655/experimental-evidence-and-in-silico-identification-of-tryptophan-decarboxylase-in-citrus-genus
#6
Luigi De Masi, Domenico Castaldo, Domenico Pignone, Luigi Servillo, Angelo Facchiano
Plant tryptophan decarboxylase (TDC) converts tryptophan into tryptamine, precursor of indolealkylamine alkaloids. The recent finding of tryptamine metabolites in Citrus plants leads to hypothesize the existence of TDC activity in this genus. Here, we report for the first time that, in Citrus x limon seedlings, deuterium labeled tryptophan is decarboxylated into tryptamine, from which successively deuterated N,N,N-trimethyltryptamine is formed. These results give an evidence of the occurrence of the TDC activity and the successive methylation pathway of the tryptamine produced from the tryptophan decarboxylation...
February 11, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28195901/prognostic-molecular-and-imaging-biomarkers-in-primary-glioblastoma
#7
Edit Bosnyák, Sharon K Michelhaugh, Neil V Klinger, David O Kamson, Geoffrey R Barger, Sandeep Mittal, Csaba Juhász
PURPOSE: Several molecular glioma markers (including isocitrate dehydrogenase 1 [IDH1] mutation, amplification of the epidermal growth factor receptor [EGFR], and methylation of the O6-methylguanine-DNA methyltransferase [MGMT] promoter) have been associated with glioblastoma survival. In this study, we examined the association between tumoral amino acid uptake, molecular markers, and overall survival in patients with IDH1 wild-type (primary) glioblastoma. PATIENTS AND METHODS: Twenty-one patients with newly diagnosed IDH1 wild-type glioblastomas underwent presurgical MRI and PET scanning with alpha[C-11]-L-methyl-tryptophan (AMT)...
May 2017: Clinical Nuclear Medicine
https://www.readbyqxmd.com/read/27998091/tryptophan-lyase-nosl-a-cornucopia-of-5-deoxyadenosyl-radical-mediated-transformations
#8
Dhananjay M Bhandari, Dmytro Fedoseyenko, Tadhg P Begley
Tryptophan lyase (NosL) is a radical S-adenosyl-l-methionine (SAM) enzyme that catalyzes the formation of 3-methyl-2-indolic acid from l-tryptophan. In this paper, we demonstrate that the 5'-deoxyadenosyl radical is considerably more versatile in its chemistry than previously anticipated: hydrogen atom abstraction from Nα-cyclopropyltryptophan occurs at Cα rather than the amino group with NosL Y90A and replacing the substrate amine with a ketone or an alkene changes the chemistry from hydrogen atom abstraction to double bond addition...
December 21, 2016: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/27997749/inhibition-of-platelet-aggregation-and-thrombosis-by-indole-alkaloids-isolated-from-the-edible-insect-protaetia-brevitarsis-seulensis-kolbe
#9
JungIn Lee, Wonhwa Lee, Mi-Ae Kim, Jae Sam Hwang, MinKyun Na, Jong-Sup Bae
Protaetia brevitarsis seulensis (Kolbe) has been temporarily registered as a food material by the Ministry of Food and Drug Safety of Korea (MFDS). The current study aimed to discover small antithrombotic molecules from this edible insect. Five indole alkaloids, 5-hydroxyindolin-2-one (1), (1R,3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (2), (1S,3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (3), (3S)-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (4) and L-tryptophan (5), were isolated from the insect...
December 20, 2016: Journal of Cellular and Molecular Medicine
https://www.readbyqxmd.com/read/27973747/quinolinic-acid-induces-neuritogenesis-in-sh-sy5y-neuroblastoma-cells-independently-of-nmda-receptor-activation
#10
Juan-Manuel Hernandez-Martinez, Caroline M Forrest, L Gail Darlington, Robert A Smith, Trevor W Stone
Glutamate and nicotinamide adenine dinucleotide (NAD(+) ) have been implicated in neuronal development and several types of cancer. The kynurenine pathway of tryptophan metabolism includes quinolinic acid (QA) which is both a selective agonist at N-methyl-D-aspartate (NMDA) receptors and also a precursor for the formation of NAD(+) . The effect of QA on cell survival and differentiation has therefore been examined on SH-SY5Y human neuroblastoma cells. Retinoic acid (RA, 10 μm) induced differentiation of SH-SY5Y cells into a neuronal phenotype showing neurite growth...
December 14, 2016: European Journal of Neuroscience
https://www.readbyqxmd.com/read/27930920/indoleamine-2-3-dioxygenase-regulates-t-cell-activity-through-vav1-rac-pathway
#11
Runmei Li, Hui Li, Qian Sun, Liang Liu, Chen Zhang, Xiubao Ren
The immunoregulatory enzyme indoleamine 2,3-dioxygenase (IDO) suppresses T-cell responses and promotes immune tolerance in tumor resistance. A previous study determined that IDO inhibits Vav1 mRNA expression and the activation of Vav1 and its downstream targets in T cells in the guanine exchange factor (GEF)-independent pathway. The current study aims to determine whether IDO induces T-cell immunosuppression through Vav1/Rac signaling pathway, which is a GEF-dependent pathway. The correlation between Vav1 mRNA expressions in T cells of tumor infiltrating lymphocytes and the levels of IDO expression in lung cancer tissues from lung cancer patients was detected...
January 2017: Molecular Immunology
https://www.readbyqxmd.com/read/27929146/reactivity-of-the-nitrogen-centered-tryptophanyl-radical-in-the-catalysis-by-the-radical-sam-enzyme-nosl
#12
Haocheng Qianzhu, Wenjuan Ji, Xinjian Ji, Leixia Chu, Chuchu Guo, Wei Lu, Wei Ding, Jiangtao Gao, Qi Zhang
The radical SAM tryptophan (Trp) lyase NosL involved in nosiheptide biosynthesis catalyzes two parallel reactions, converting l-Trp to 3-methyl-2-indolic acid (MIA) and to dehydroglycine and 3-methylindole, respectively. The two parallel reactions diverge from a nitrogen-centered tryptophanyl radical intermediate. Here we report an investigation on the intrinsic reactivity of the tryptophanyl radical using a chemical model study and DFT calculations. The kinetics of the formation and fragmentation of this nitrogen-centered radical in NosL catalysis were also studied in detail...
December 22, 2016: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/27805190/a-study-of-dna-bsa-interaction-and-catalytic-potential-of-oxidovanadium-v-complexes-with-ono-donor-ligands
#13
Subhashree P Dash, Alok K Panda, Sarita Dhaka, Sagarika Pasayat, Ashis Biswas, Mannar R Maurya, Paresh Kumar Majhi, Aurélien Crochet, Rupam Dinda
The study of DNA/BSA interaction and the catalytic potential of four mononuclear oxidoalkoxido vanadium(v) [V(V)O(L(1-4))OEt] (1-4) and one dinuclear oxidoalkoxido mixed-ligand vanadium(v) [{VO(L(2))OEt}2(Q)]{Q = 4,4'-bipyridine}(5) complexes, with tridentate binegative aroylazine ligands are reported [where H2L(1) = anthranylhydrazone of 2-hydroxy-1-napthaldehyde, H2L(2) = salicylhydrazone of 2-hydroxy-1-napthaldehyde, H2L(3) = benzoylhydrazone of 2-hydroxy-1-acetonaphthone, H2L(4) = anthranylhydrazone of 2-hydroxy-1-acetonaphthone]...
November 2, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/27776479/enhanced-metabolic-process-to-indole-alkaloids-in-clematis-terniflora-dc-after-exposure-to-high-level-of-uv-b-irradiation-followed-by-the-dark
#14
Cuixia Gao, Bingxian Yang, Dandan Zhang, Meng Chen, Jingkui Tian
BACKGROUND: Indole alkaloids, which characteristically contain an indole nucleus, have pharmaceutical potential in a diverse range of applications. UV-B can elicit the accumulation of indole alkaloids. The indole alkaloid (6-hydroxyl-1H-indol-3-yl) carboxylic acid methyl ester with cytotoxic activity was found to accumulate in Clematis terniflora DC. leaves after exposure to high level of UV-B irradiation and the dark. However, a more in-depth analysis of the process behind this response has not yet been performed...
October 24, 2016: BMC Plant Biology
https://www.readbyqxmd.com/read/27765857/assessment-of-tryptophan-uptake-and-kinetics-using-1-2-18f-fluoroethyl-l-tryptophan-and-%C3%AE-11c-methyl-l-tryptophan-pet-imaging-in-mice-implanted-with-patient-derived-brain-tumor-xenografts
#15
Sharon K Michelhaugh, Otto Muzik, Anthony R Guastella, Neil V Klinger, Lisa A Polin, Hancheng Cai, Yangchun Xin, Thomas J Mangner, Shaohui Zhang, Csaba Juhász, Sandeep Mittal
Abnormal tryptophan metabolism via the kynurenine pathway is involved in the pathophysiology of a variety of human diseases including cancers. α-(11)C-methyl-l-tryptophan ((11)C-AMT) PET imaging demonstrated increased tryptophan uptake and trapping in epileptic foci and brain tumors, but the short half-life of (11)C limits its widespread clinical application. Recent in vitro studies suggested that the novel radiotracer 1-(2-(18)F-fluoroethyl)-l-tryptophan ((18)F-FETrp) may be useful to assess tryptophan metabolism via the kynurenine pathway...
February 2017: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
https://www.readbyqxmd.com/read/27755995/the-photobleaching-of-the-free-and-encapsulated-metallic-phthalocyanine-and-its-effect-on-the-photooxidation-of-simple-molecules
#16
Brenda Gomes Fanchiotti, Marcella Piffer Zamprogno Machado, Letícia Camilato de Paula, Mahmut Durmuş, Tebello Nyokong, Arlan da Silva Gonçalves, André Romero da Silva
The photobleaching of an unsubstituted phthalocyanine (gallium(III) phthalocyanine chloride (GaPc)) and a substituted phthalocyanine (1,4-(tetrakis[4-(benzyloxy)phenoxy]phthalocyaninato) indium(III) chloride (InTBPPc)) was monitored for the free photosensitizers and for the phthalocyanines encapsulated into nanoparticles of PEGylated poly(D,L-lactide-co-glycolide) (PLGA-PEG). Phosphate-buffered solutions (PBS) and organic solutions of the free GaPc or the free InTBPPc, and suspensions of each encapsulated photosensitizer (2-15μmol/L) were irradiated using a laser diode of 665nm with a power of 1-104mW and a light dose of 7...
December 2016: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/27750145/synthesis-spectroscopic-properties-and-photodynamic-activity-of-two-cationic-bodipy-derivatives-with-application-in-the-photoinactivation-of-microorganisms
#17
Maximiliano L Agazzi, M Belén Ballatore, Eugenia Reynoso, Ezequiel D Quiroga, Edgardo N Durantini
Two cationic BODIPYs 3 and 4 were synthesized by acid-catalyzed condensation of the corresponding pyrrole and benzaldehyde, followed by complexation with boron and methylation. Compound 3 contains methyl at the 1,3,5 and 7 positions of the s-indacene ring and a N,N,N-trimethylamino group attached to the phenylene unit, while 4 is not substituted by methyl groups and the cationic group is bound by an aliphatic spacer. UV-visible absorption spectra of these BODIPYs show an intense band at ∼500 nm in solvents of different polarities and n-heptane/sodium bis(2-ethylhexyl)sulfosuccinate (AOT)/water reverse micelles...
January 27, 2017: European Journal of Medicinal Chemistry
https://www.readbyqxmd.com/read/27714299/characterisation-of-6-dmatsmo-from-micromonospora-olivasterospora-leading-to-identification-of-the-divergence-in-enantioselectivity-regioselectivity-and-multiple-prenylation-of-tryptophan-prenyltransferases
#18
Julia Winkelblech, Xiulan Xie, Shu-Ming Li
Prenylated secondary metabolites including indole derivatives usually demonstrate improved biological and pharmacological activities, which make them promising candidates for drug discovery and development. The transfer reactions of a prenyl moiety from a prenyl donor, e.g. dimethylallyl diphosphate (DMAPP), to an acceptor is catalysed by prenyltransferases. One special group of such enzymes uses DMAPP and tryptophan as substrates with dimethylallyltryptophans as reaction products and functions therefore as dimethylallyltryptophan synthases (DMATSs)...
October 18, 2016: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/27707604/synthesis-and-biological-evaluation-of-ricinoleic-acid-based-lipoamino-acid-derivatives
#19
Y Mohini, R B N Prasad, M S L Karuna, Y Poornachandra, C Ganesh Kumar
A series of novel ricinoleic acid based lipoamino acid derivatives were synthesized from (Z)-methyl-12-aminooctadec-9-enoate and different l-amino acids (glycine, alanine, phenyl alanine, valine, leucine, isoleucine, proline and tryptophan). The structures of all the prepared compounds were characterized by (1)H NMR, (13)C NMR and mass spectral studies. The title compounds were evaluated for their antimicrobial and anti-biofilm activities. Among all the derivatives, compound 7a (Z)-methyl-12-(2-aminoacetamido)octadec-9-enoate exhibited promising antibacterial activity (MIC, 3...
September 28, 2016: Bioorganic & Medicinal Chemistry Letters
https://www.readbyqxmd.com/read/27696676/severity-of-experimental-traumatic-brain-injury-modulates-changes-in-concentrations-of-cerebral-free-amino-acids
#20
Angela Maria Amorini, Giacomo Lazzarino, Valentina Di Pietro, Stefano Signoretti, Giuseppe Lazzarino, Antonio Belli, Barbara Tavazzi
In this study, concentrations of free amino acids (FAA) and amino group containing compounds (AGCC) following graded diffuse traumatic brain injury (mild TBI, mTBI; severe TBI, sTBI) were evaluated. After 6, 12, 24, 48 and 120 hr aspartate (Asp), glutamate (Glu), asparagine (Asn), serine (Ser), glutamine (Gln), histidine (His), glycine (Gly), threonine (Thr), citrulline (Cit), arginine (Arg), alanine (Ala), taurine (Tau), γ-aminobutyrate (GABA), tyrosine (Tyr), S-adenosylhomocysteine (SAH), l-cystathionine (l-Cystat), valine (Val), methionine (Met), tryptophane (Trp), phenylalanine (Phe), isoleucine (Ile), leucine (Leu), ornithine (Orn), lysine (Lys), plus N-acetylaspartate (NAA) were determined in whole brain extracts (n = 6 rats at each time for both TBI levels)...
March 2017: Journal of Cellular and Molecular Medicine
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