keyword
MENU ▼
Read by QxMD icon Read
search

Amino acid

keyword
https://www.readbyqxmd.com/read/28738566/preparation-and-evaluation-of-a-novel-n-benzyl-phenethylamino-%C3%AE-cyclodextrin-bonded-chiral-stationary-phase-for-hplc
#1
Liang Li, Biaoping Cheng, Rendan Zhou, Zhigang Cao, Chun Zeng, Laisheng Li
A novel N-benzyl-phenethylamino-β-cyclodextrin-bonded ordered mesoporous SBA-15 chiral stationary phase (BZCDP) for high-performance liquid chromatography (HPLC) was prepared. The structure and morphology of the ligand and the stationary phase were characterized by mass spectrometry, elemental analysis, infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and thermogravimetric analysis. The enantiomers of chiral compounds including nine common β-adrenergic blocker drugs (β-blockers), eight dansyl amino acids (DNS-AA) and six flavanones were successfully separated by polar organic solvent and reversed-phase chromatography, respectively...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738559/a-novel-dianionic-amino-acid-ionic-liquid-coated-peg-4000-modified-fe3o4-nanocomposite-for-the-magnetic-solid-phase-extraction-of-trypsin
#2
Qin Yang, Yuzhi Wang, Hongmei Zhang, Kaijia Xu, Xiaoxiao Wei, Panli Xu, Yigang Zhou
A novel magnetic extractant, PEG 4000 modified Fe3O4nanomaterial that coated with dianionic amino acid ionic liquid (Fe3O4@PEG@DAAAIL), was successfully synthesized and characterized. X-ray diffraction (XRD), transmission electron microscope (TEM), vibrating sample magnetometer (VSM), fourier transform infrared spectrometry (FT-IR), thermal gravimetric analysis (TGA) and zeta potentials were used to confirm that the novel nanocomposite was successfully synthesized. Subsequently, the prepared Fe3O4@PEG@DAAAIL nanocomposite was used as the extractant for trypsin coupled with magnetic solid-phase extraction (MSPE)...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738503/integration-of-protein-extraction-with-a-stream-of-byproducts-from-marine-macroalgae-a-model-forms-the-basis-for-marine-bioeconomy
#3
Tejal K Gajaria, Poornima Suthar, Ravi S Baghel, Nikunj B Balar, Preeti Sharnagat, Vaibhav A Mantri, C R K Reddy
The present study describes an advanced biorefinery model for marine macroalgae that assumes significant importance in the context of marine bio-economy. The method investigated in this study integrates the extraction of crude proteins with recovery of minerals rich sap, lipids, ulvan and cellulose from fresh biomass of Ulva lactuca. The protein content extracted was 11±2.12% on dry weight basis with recovery efficiency of 68.75±4.01%. The amino acid composition of crude protein fraction showed iso-leucine as the most abundant amino acid with 16...
July 5, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28738332/neuroprogression-and-immune-activation-in-major-depressive-disorder
#4
Jeffrey H Meyer
Traditionally, the neurobiology of major depressive disorder (MDD) has been largely considered from the perspective of the state of major depressive episodes (MDE) versus being in remission, but the current accumulation of disease markers, largely acquired cross-sectionally, is strongly suggestive of neuroprogressive aspects of MDD. This chapter focuses on the changes in disease markers involved in the reorganization of the nervous system in MDD, including the translocator protein (TSPO; an index of microglial activation), glial fibrillary acidic protein (GFAP; an index of astroglial activation), [11C]harmine (a marker of monoamine oxidase A; MAO-A), and several other indices (metabotropic glutamate receptor 5 [mGluR5], excitatory amino acid transporters, and magnetic resonance imaging spectroscopy measurements) of glutamate dysregulation...
2017: Modern Trends in Pharmacopsychiatry
https://www.readbyqxmd.com/read/28738307/pharmacological-characterization-and-binding-modes-of-novel-racemic-and-optically-active-phenylalanine-based-antagonists-of-ampa-receptors
#5
Ewa Szymańska, Birgitte Nielsen, Tommy N Johansen, Ana Maria Cuñado Moral, Darryl S Pickering, Katarzyna Szczepańska, Anna Mickowska, Katarzyna Kieć-Kononowicz
In order to map out molecular determinants for the competitive blockade of AMPA receptor subtypes, a series of racemic aryl-substituted phenylalanines was synthesized and pharmacologically characterized in vitro at native rat ionotropic glutamate receptors. Most of the compounds showed micromolar affinity and preference for AMPA receptors. Individual stereoisomers of selected compounds were further evaluated at recombinant homomeric rat GluA2 and GluA3 receptors. The most potent compound, (-)-2-amino-3-(6-chloro-2',5'-dihydroxy-5-nitro-[1,1'-biphenyl]-3-yl)propanoic acid, the expected R-isomer showing Ki of 1...
July 8, 2017: European Journal of Medicinal Chemistry
https://www.readbyqxmd.com/read/28738245/two-amino-acids-change-in-the-nsp4-of-sars-coronavirus-abolishes-viral-replication
#6
Yusuke Sakai, Kengo Kawachi, Yutaka Terada, Hiroko Omori, Yoshiharu Matsuura, Wataru Kamitani
Infection with coronavirus rearranges the host cell membrane to assemble a replication/transcription complex in which replication of the viral genome and transcription of viral mRNA occur. Although coexistence of nsp3 and nsp4 is known to cause membrane rearrangement, the mechanisms underlying the interaction of these two proteins remain unclear. We demonstrated that binding of nsp4 with nsp3 is essential for membrane rearrangement and identified amino acid residues in nsp4 responsible for the interaction with nsp3...
July 21, 2017: Virology
https://www.readbyqxmd.com/read/28738242/specialized-metabolites-from-the-aerial-parts-of-centaurea-polyclada-dc
#7
Serdar Demir, Canan Karaalp, Erdal Bedir
The genus Centaurea L. (Asteraceae) is represented by 200 taxa in the flora of Turkey and several Centaurea species are used as herbal remedies against different conditions. Previous phytochemical investigations on this genus generally revealed the isolation of sesquiterpene lactones and flavonoid derivatives. In our continuous search on Centaurea genus, a phytochemical study was performed on Centaurea polyclada DC., an endemic of West Anatolia. Previously undescribed two sesquiterpene-amino acid conjugates, an elemane and an eudesmane derivative were isolated from the aerial parts of Centaurea polyclada, together with eight known compounds; two elemane derivatives, three flavonoids, a lignan, a phenolic glucoside and a phenylpropanoid glucoside...
July 21, 2017: Phytochemistry
https://www.readbyqxmd.com/read/28738163/a-local-duplication-of-the-i-melanocortin-receptor-1-i-locus-in-i-astyanax-i
#8
Joshua B Gross, James Weagley, Bethany A Stahl, Li Ma, Luis Espinasa, Suzanne E McGaugh
In this study, we report evidence of a novel duplication of <i>Melanocortin receptor 1 (Mc1r)</i> in the cavefish genome. This locus was discovered following the observation of excessive allelic diversity in a ~820 bp fragment of <i>Mc1r</i> amplified via degenerate PCR from a natural population of <i>Astyanax aeneus</i> fish from Guerrero, Mexico. The cavefish genome reveals the presence of two closely related <i>Mc1r</i> open reading frames separated by a 1...
July 24, 2017: Genome Génome / Conseil National de Recherches Canada
https://www.readbyqxmd.com/read/28738149/supported-and-unsupported-chiral-squaramides-as-organocatalysts-for-stereoselective-michael-additions-synthesis-of-enantiopure-chromenes-and-spirochromanes
#9
Jose Maria Andres, Jorge Losada, Alicia Maestro, Patricia Rodríguez-Ferrer, Rafael Pedrosa
Novel supported chiral bifunctional squaramides have been easily prepared starting from diamines derived from natural amino acids and commercially available aminoalkyl polystyrene resins. These squaramides behave as excellent stereoselective recoverable organocatalysts in different Michael additions, in neat conditions at room temperature. The reaction on 2-(2-nitrovinyl) phenol as electrophile lead, in excellent yields and enantioselectivities, to intermediates that can be easily transformed into 4H-chromenes, and spirochromanones...
July 24, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28738073/the-n-terminal-region-of-serum-amyloid-a3-protein-activates-nf-%C3%AE%C2%BAb-and-up-regulates-muc2-mucin-mrna-expression-in-mouse-colonic-epithelial-cells
#10
Manami Tashiro, Ami Iwata, Marika Yamauchi, Kaori Shimizu, Ayaka Okada, Naotaka Ishiguro, Yasuo Inoshima
Serum amyloid A (SAA) is the major acute-phase protein and a precursor of amyloid A (AA) in AA amyloidosis in humans and animals. SAA isoforms have been identified in a wide variety of animals, such as SAA1, SAA2, SAA3, and SAA4 in mouse. Although the biological functions of SAA isoforms are not completely understood, recent studies have suggested that SAA3 plays a role in host defense. Expression of SAA3 is increased on the mouse colon surface in the presence of microbiota in vivo, and it increases mRNA expression of mucin 2 (MUC2) in murine colonic epithelial cells in vitro, which constitutes a protective mucus barrier in the intestinal tract...
2017: PloS One
https://www.readbyqxmd.com/read/28738064/species-a-rotavirus-nsp3-acquires-its-translation-inhibitory-function-prior-to-stable-dimer-formation
#11
Hugo I Contreras-Treviño, Edgar Reyna-Rosas, Renato León-Rodríguez, Blanca H Ruiz-Ordaz, Tzvetanka D Dinkova, Ana M Cevallos, Luis Padilla-Noriega
Species A rotavirus non-structural protein 3 (NSP3) is a translational regulator that inhibits or, under some conditions, enhances host cell translation. NSP3 binds to the translation initiation factor eIF4G1 and evicts poly-(A) binding protein (PABP) from eIF4G1, thus inhibiting translation of polyadenylated mRNAs, presumably by disrupting the effect of PABP bound to their 3'-ends. NSP3 has a long coiled-coil region involved in dimerization that includes a chaperone Hsp90-binding domain (HS90BD). We aimed to study the role in NSP3 dimerization of a segment of the coiled-coil region adjoining the HS90BD...
2017: PloS One
https://www.readbyqxmd.com/read/28737941/unveiling-the-catalytic-role-of-b-block-histidine-in-the-n-s-acyl-shift-step-of-protein-splicing
#12
Jon I Mujika, Xabier Lopez
Protein splicing is a post-translational modification that involves the excision of a segment denoted as intein and the joining of its two flanking segments. The process is auto-catalytic, making inteins appealing for many applications in biotechnology, bioengineering, or medicine. The canonical mechanism of protein splicing is composed of four sequential steps, and is initialized by an N-S or N-O acyl shift to form a linear ester. It is well established that a histidine, the most conserved amino acid in all inteins catalyzes this initial step, even though its role remains to be understood...
July 24, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28737906/role-of-the-protein-dimeric-interface-in-allosteric-inhibition-of-n-acetyl-aspartate-hydrolysis-by-human-aspartoacylase
#13
Ekaterina D Kots, Sofya V Lushchekina, Sergey D Varfolomeev, Alexander V Nemukhin
The results of molecular modeling suggest a mechanism of allosteric inhibition upon hydrolysis of N-acetyl-aspartate (NAA), one of the most abundant amino acid derivatives in brain, by human aspartoacylase (hAsp). Details of this reaction are important to suggest the practical ways to control the enzyme activity. Search for allosteric sites using the Allosite web server and SiteMap analysis allowed us to identify substrate binding pockets located at the interface between the subunits of the hAsp dimer molecule...
July 24, 2017: Journal of Chemical Information and Modeling
https://www.readbyqxmd.com/read/28737899/%C3%AE-amino-acid-derived-benzimidazole-linked-rhodamines-a-case-of-substitution-effect-at-the-amino-acid-site-toward-spiro-ring-opening-for-selective-sensing-of-al-3-ions
#14
Anupam Majumdar, Subhendu Mondal, Constantin G Daniliuc, Debashis Sahu, Bishwajit Ganguly, Sourav Ghosh, Utpal Ghosh, Kumaresh Ghosh
α-Amino acid derived benzimidazole-linked rhodamines have been synthesized, and their metal ion sensing properties have been evaluated. Experimentally, l-valine- and l-phenylglycine-derived benzimidazole-based rhodamines 1 and 2 selectively recognize Al(3+) ion in aqueous CH3CN (CH3CN/H2O 4/1 v/v, 10 mM tris HCl buffer, pH 7.0) over the other cations by exhibiting color and "turn-on" emission changes. In contrast, glycine-derived benzimidazole 3 remains silent in the recognition event and emphasizes the role of α-substitution of amino acid undertaken in the design...
July 24, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28737895/cell-wall-remodeling-of-staphylococcus-aureus-in-live-c-elegans
#15
Sean E Pidgeon, Marcos M Pires
Peptidoglycan (PG) scaffolds are critical components of bacterial cell walls. They counter internal turgor pressure to prevent lysis and protect against external insults. It was recently discovered that various types of bacteria release large quantities of PG building blocks (D-amino acids) into their surrounding medium. Cultured bacteria were also found to incorporate D-amino acids (both natural and synthetic) from the medium directly into their PG scaffold. Together, these two processes may potentially function, in concert, to metabolically remodel PG in live host organisms...
July 24, 2017: Bioconjugate Chemistry
https://www.readbyqxmd.com/read/28737807/npy-binds-with-heme-to-form-a-npy-heme-complex-enhancing-peroxidase-activity-in-free-heme-and-promoting-npy-nitration-and-inactivation
#16
Huixian Ye, Zhen Yang, Hailing Li, Zhonghong Gao
Neuropeptide Y (NPY) is a member of the pancreatic peptide family of neuropeptides that play a crucial role in numerous central and peripheral nervous system responses. Recently, it has been shown that NPY protects cells against neurotoxic damage from β-amyloid peptides (Aβ) in Alzheimer's disease (AD). Heme is a common factor linking several metabolic perturbations in AD and altered heme metabolism has been shown to be related to the pathologies of AD. Thus, heme may have a chance to act on NPY and potentially counteract its function...
July 24, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28737695/predictive-structure-and-topology-of-peroxisomal-atp-binding-cassette-abc-transporters
#17
Pierre Andreoletti, Quentin Raas, Catherine Gondcaille, Mustapha Cherkaoui-Malki, Doriane Trompier, Stéphane Savary
The peroxisomal ATP-binding Cassette (ABC) transporters, which are called ABCD1, ABCD2 and ABCD3, are transmembrane proteins involved in the transport of various lipids that allow their degradation inside the organelle. Defective ABCD1 leads to the accumulation of very long-chain fatty acids and is associated with a complex and severe neurodegenerative disorder called X-linked adrenoleukodystrophy (X-ALD). Although the nucleotide-binding domain is highly conserved and characterized within the ABC transporters family, solid data are missing for the transmembrane domain (TMD) of ABCD proteins...
July 22, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28737579/prostate-specific-membrane-antigen-targeted-imaging-with-18f-dcfpyl-in-high-grade-gliomas
#18
Roberto Andres Salas Fragomeni, Joshua R Menke, Matthias Holdhoff, Clare Ferrigno, John Joseph Laterra, Lilja B Solnes, Mehrbod S Javadi, Zsolt Szabo, Martin G Pomper, Steven P Rowe
High-grade gliomas (World Health Organization grade III-IV) are highly lethal primary brain tumors. Imaging modalities, including MRI and FDG PET, provide a limited ability to differentiate treatment effects (such as radiation necrosis) from recurrent or residual tumor. As the first step in validating the applicability of prostate-specific membrane antigen (PSMA)-targeted imaging in high-grade gliomas, we evaluated the ability of the PSMA-targeted small molecule [F]DCFPyL (2-(3-(1carboxy-5-(6-[F]fluoro-pyridine-3-carbonyl)-amino]-pentyl)-ureido)-pentanedioic acid) to image high-grade gliomas in a series of 3 prospectively recruited patients...
July 22, 2017: Clinical Nuclear Medicine
https://www.readbyqxmd.com/read/28737471/quality-control-by-trans-editing-factor-prevents-global-mistranslation-of-non-protein-amino-acid-%C3%AE-aminobutyrate
#19
Jo Marie Bacusmo, Alexandra B Kuzmishin, William A Cantara, Yuki Goto, Hiroaki Suga, Karin Musier-Forsyth
Accuracy in protein biosynthesis is maintained through multiple pathways, with a critical checkpoint occurring at the tRNA aminoacylation step catalyzed by aminoacyl-tRNA synthetases (ARSs). In addition to the editing functions inherent to some synthetases, single-domain trans-editing factors, which are structurally homologous to ARS editing domains, have evolved as alternative mechanisms to correct mistakes in aminoacyl-tRNA synthesis. To date, ARS-like trans-editing domains have been shown to act on specific tRNAs that are mischarged with genetically encoded amino acids...
July 24, 2017: RNA Biology
https://www.readbyqxmd.com/read/28737429/hif-1%C3%AE-inhibition-by-diethylstilbestrol-and-its-polyacetal-conjugate-in-hypoxic-prostate-tumour-cells-insights-from-nmr-metabolomics
#20
Ana Armiñán, Luís Mendes, Joana Carrola, Julie Movellan, María J Vicent, Iola F Duarte
In this study, we have employed (1)H NMR metabolomics to assess the metabolic responses of PC3 prostate tumour cells to hypoxia and to pharmacological HIF-1α inhibition by DES or its polyacetal conjugate tert-DES. Oxygen deprivation prompted a number of changes in intracellular composition and metabolic activity, mainly reflecting upregulated glycolysis, amino acid catabolism and other compensatory mechanisms used by hypoxic cells to deal with oxidative imbalance and energy deficit. Cell treatment with a non-cytotoxic concentration of DES, under hypoxia, triggered significant changes in 17 metabolites...
July 24, 2017: Journal of Drug Targeting
keyword
keyword
4154
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"