keyword
MENU ▼
Read by QxMD icon Read
search

Glycopeptide

keyword
https://www.readbyqxmd.com/read/28231529/new-enantioselective-lc-method-development-and-validation-for-the-assay-of-modafinil
#1
Marianna Harvanová, Taťána Gondová
For the first time, a new, fast and sensitive chromatographic method for the separation and determination of modafinil enantiomers was developed on chiral stationary phase with macrocyclic glycopeptide teicoplanin in the polar organic mode. The effect of the mobile phase composition and column temperature on the retention and enantioseparation were studied. The separation was performed using a Chirobiotic T column (250×4.6mm, 5μm) with methanol and triethylamine (100/0.05, v/v) as the mobile phase at a flow rate of 1...
February 16, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28228089/genotypic-characterization-of-vancomycin-resistant-enterococcus-spp-in-tertiary-center-iran
#2
Shervin Shokouhi, Ilad Alavi Darazam, Matin Rouhani, Mahdiyeh Ghasemnejad
BACKGROUND: Enterococci infection rate, mortality and morbidity has been increased in recent decades accompanied by progressive emerging antimicrobial resistance. Vancomycin-resistant enterococci (VRE), important pathogen in hospitalized patients, have distinct antibiotic susceptibility to glycopeptides that varied genetically and can influence in choosing therapeutic agents. In this study, we aimed to determine the patterns of antimicrobial resistance according to the genotypic variations in VREs...
February 10, 2017: Infectious Disorders Drug Targets
https://www.readbyqxmd.com/read/28221772/desleucyl-oritavancin-with-a-damaged-d-ala-d-ala-binding-site-inhibits-the-transpeptidation-step-of-cell-wall-biosynthesis-in-whole-cells-of-staphylococcus-aureus
#3
Sung Joon Kim, Manmilan Singh, Shasad Sharif, Jacob Schaefer
We have used solid-state NMR to characterize the exact nature of the dual mode of action of oritavancin in preventing cell-wall assembly in Staphylococcus aureu. Measurements performed on whole cells labeled selectively in vivo have established that des-N-methylleucyl-N-4-(4-fluorophenyl)benzyl-chloroeremomycin, an Edman degradation product of [19F]oritavancin, which has a damaged D-Ala-D-Ala binding aglycon, is a potent inhibitor of the transpeptidase activity of cell-wall biosynthesis. The desleucyl-drug binds to partially cross-linked peptidoglycan by a cleft formed between the drug aglycon and its biphenyl hydrophobic sidechain...
February 21, 2017: Biochemistry
https://www.readbyqxmd.com/read/28218515/chlorinated-glycopeptide-antibiotic-peptide-precursors-improve-cytochrome-p450-catalyzed-cyclization-cascade-efficiency
#4
Madeleine Peschke, Clara Brieke, Rob Goode, Ralf Schittenhelm, Max J Cryle
The activity of glycopeptide antibiotics depends upon important structural modifications to their precursor heptapeptide backbone: specifically, the Cytochrome P450-catalyzed oxidative crosslinking of aromatic side chains as well as the halogenation of specific residues within the peptide. The timing of halogenation and its effect on the cyclization of the peptide is currently unclear. Our results show that chlorination of peptide precursors improves their processing by P450 enzymes in vitro, which provides support for GPA halogenation occurring prior to peptide cyclization during non-ribosomal peptide synthesis...
February 20, 2017: Biochemistry
https://www.readbyqxmd.com/read/28216796/design-and-synthesis-of-nanofibers-of-self-assembled-de-novo-glycoconjugates-towards-mucosal-lining-restoration-and-anti-inflammatory-drug-delivery
#5
Jie Zhou, Michael O'Keeffe, Gongxian Liao, Fan Zhao, Cox Terhorst, Bing Xu
The medical practice for IBD is solely based on anti-inflammatory drugs, but the outcome is far from ideal. Our long-term research goal is to seek a better clinical outcome by combining the anti-inflammatory therapy with physical mucus layer restoration. As the first step towards that objective, we choose to develop self-assembled hydrogels of de novo glycoconjugates that consist of anti-inflammatory drugs and glycopeptides. By covalently linking peptides (e.g., nap-phe-phe-lys), saccharides (e.g., glucosamine), and an anti-inflammatory drug (i...
October 6, 2016: Tetrahedron
https://www.readbyqxmd.com/read/28215026/separation-of-peptides-on-superficially-porous-particle-based-macrocyclic-glycopeptide-liquid-chromatography-stationary-phases-consideration-of-fast-separations
#6
Rasangi M Wimalasinghe, Zachary S Breitbach, Jauh T Lee, Daniel W Armstrong
Macrocyclic glycopeptide based liquid chromatography stationary phases are known for their highly selective peptide separations. Fast and ultrafast (t R < 1 min) high-efficiency separations were achieved with superficially porous particle (SPP)-based stationary phases. Separations of pharmaceutically important classes of peptides such as enkephalins and bradykinins have been achieved in less than 5 min in isocratic elution modes. Selectivity for peptides structurally similar to one another was increased with use of teicoplanin-based stationary phases compared with commercial C18 stationary phases...
February 18, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28213217/selective-enrichment-of-glycopeptides-phosphopeptides-using-fe3o4-au-b-oh-2-mtio2-core-shell-microspheres
#7
Dongpo Xu, Guoquan Yan, Mingxia Gao, Chunhui Deng, Xiangmin Zhang
In this work, the bifunctional Fe3O4@Au-B(OH)2@mTiO2 core-shell core-shell microspheres were designed and synthesized for the selective enrichment of glycopeptides/ phosphopeptides. Due to the bifunctional property of the titanium dioxide and the boronic acid group, the microspheres were successfully applied to the enrichment of phosphopeptides and glycopeptides, evaluated by capturing phosphopeptides from tryptic digestion of model phosphoprotein bovine β-casein diluted to 2.0pgμL(-1) (8.0×10(-17)molμL(-1)) and glycopeptides from tryptic digestion of model glycoprotein horseradish peroxidase (HRP) diluted to 80pgμL(-1) (2...
May 1, 2017: Talanta
https://www.readbyqxmd.com/read/28211926/protecting-group-free-synthesis-of-glycosyl-thiols-from-reducing-sugars-in-water-application-to-the-production-of-n-glycan-glycoconjugates
#8
S R Alexander, D Lim, Z Amso, M A Brimble, A J Fairbanks
Glycosyl thiols may be accessed from the corresponding reducing sugars in water without recourse to any sugar projecting groups by way of a DMC mediated reaction with thioacetic acid in the presence of base, and hydrolysis of the anomeric thioacetate. Glycosyl thiols produced by this method may be used to access glycoconjugates, such as glycopeptides by use of the thiol-ene click reaction.
February 17, 2017: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/28208257/hydrophilic-interaction-chromatography-hyphenated-with-mass-spectrometry-a-powerful-analytical-tool-for-the-comparison-of-originator-and-biosimilar-therapeutic-monoclonal-antibodies-at-the-middle-up-level-of-analysis
#9
Valentina D'Atri, Szabolcs Fekete, Alain Beck, Matthew Lauber, Davy Guillarme
The development and approval processes of biosimilar mAbs depend on their comparability to originators. Therefore, analytical comparisons are required to assess structural features and post-translational modifications (PTM) and thereby minimize the risk of being clinically meaningful differences between biosimilar and originator drug products. The glycosylation pattern of mAbs is considered to be an important critical quality attribute (CQA), and several analytical approaches have been proposed that facilitate characterizing and monitoring a glycosylation profile, albeit mainly at a glycan and glycopeptide level of analysis...
February 7, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28199111/parallel-comparison-of-n-linked-glycopeptide-enrichment-techniques-reveals-extensive-glycoproteomic-analysis-of-plasma-enabled-by-sax-erlic
#10
Sarah M Totten, Christa L Feasley, Abel Bermudez, Sharon J Pitteri
Protein glycosylation is of increasing interest due to its important roles in protein function and aberrant expression with disease. Characterizing protein glycosylation remains analytically challenging due to its low abundance, ion suppression issues, and microheterogeneity at glycosylation sites, especially in complex samples such as human plasma. In this study, the utility of three common N-linked glycopeptide enrichment techniques is compared using human plasma. By analysis on an LTQ-Orbitrap Elite mass spectrometer, electrostatic repulsion hydrophilic interaction liquid chromatography using strong anion exchange solid-phase extraction (SAX-ERLIC) provided the most extensive N-linked glycopeptide enrichment when compared with multilectin affinity chromatography (M-LAC) and Sepharose-HILIC enrichments...
February 15, 2017: Journal of Proteome Research
https://www.readbyqxmd.com/read/28199092/application-of-a-quantitative-lc-ms-multi-attribute-method-for-monitoring-site-specific-glycan-heterogeneity-on-a-monoclonal-antibody-containing-two-n-linked-glycosylation-sites
#11
Tian Wang, Lily Chu, Wenzhou Li, Kenneth A Lawson, Izydor Apostol, Tamer Eris
A significant challenge of traditional glycan mapping techniques is that they do not provide site-specific glycosylation information. Therefore, for proteins containing multiple glycosylation sites, the individual glycan species present at a particular site cannot be differentiated from those species present at the other glycosylation sites on the molecule. Quantification of glyco-form has previously been demonstrated using a multi-attribute method (MAM), which can quantify multiple post-translational modifications including deamidation, oxidation, glycosylation variants, and fragmentation1...
February 15, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28196325/decoding-of-o-linked-glycosylation-by-mass-spectrometry
#12
SriHariRaju Mulagapati, Veerendra Koppolu, T Shantha Raju
Protein glycosylation (N-, and O- linked) plays an important role in many biological processes including the protein structure and function. However, the structural elucidation of glycans, specifically O-linked glycans remains a major challenge and is often overlooked during protein analysis. Recently, mass spectrometry (MS) is maturing as a powerful technology for high-quality analytical characterization of O-linked glycans. This article summarizes the recent developments and insights of MS based glycomics technology, which focus on mucin type O-glycan analysis...
February 14, 2017: Biochemistry
https://www.readbyqxmd.com/read/28195591/correction-synthesis-and-immunological-evaluation-of-muc1-glycopeptide-conjugates-bearing-n-acetyl-modified-stn-derivatives-as-anticancer-vaccines
#13
An Xiao, Xiu-Jing Zheng, Chengcheng Song, Yue Gui, Chang-Xin Huo, Xin-Shan Ye
Correction for 'Synthesis and immunological evaluation of MUC1 glycopeptide conjugates bearing N-acetyl modified STn derivatives as anticancer vaccines' by An Xiao et al., Org. Biomol. Chem., 2016, 14, 7226-7237.
February 14, 2017: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/28193043/removal-of-n-linked-glycosylations-at-acidic-ph-by-pngase-a-facilitates-hydrogen-deuterium-exchange-mass-spectrometry-analysis-of-n-linked-glycoproteins
#14
Pernille Foged Jensen, Gerard Comamala, Morten Beck Trelle, Jeppe Buur Madsen, Thomas J D Jørgensen, Kasper D Rand
Protein glycosylation is the most frequent post-translational modification and is present on more than 50% of eukaryotic proteins. Glycosylation covers a wide subset of modifications involving many types of complex oligosaccharide structures, making structural analysis of glycoproteins and their glycans challenging for most analytical techniques. Hydrogen/deuterium exchange monitored by mass spectrometry is a sensitive technique for investigation of protein conformational dynamics of complex heterogeneous proteins in solution...
December 20, 2016: Analytical Chemistry
https://www.readbyqxmd.com/read/28190897/synthesis-of-multivalent-glycopeptide-conjugates-that-mimic-an-hiv-epitope
#15
Jennifer K Bailey, Dung N Nguyen, Satoru Horiya, Isaac J Krauss
Recently, we reported a directed evolution method which enabled us to discover sequences of glycopeptides that bind with picomolar affinity to HIV antibody 2G12 and are of interest as HIV vaccine candidates. In this manuscript, we describe the syntheses of several of these large (~11-12 kDa) glycopeptides by a combination of fast flow peptide synthesis and click chemistry. We also discuss the optimization of their attachment to carrier protein CRM197, affording antigenic and immunogenic conjugates ready for animal vaccination...
October 6, 2016: Tetrahedron
https://www.readbyqxmd.com/read/28188799/structure-elucidation-and-immunological-activity-of-a-novel-glycopeptide-from-mannatide
#16
Yanhong Shen, Mengqi Wu, Zhizhen Xu, Yanfei Wan, Li Zhang, Wenqing Zhang, Wei Xia
A water-soluble glycopeptide, designated as MTW, was isolated and purified from crude mannatide by DEAE-Sepharose. MTW showed one symmetrical peak on HPGPC with an average molecular weight of 2.95×10(4)Da. MTW contained 16 kinds of amino acids and the total amino acid content was 0.95%. The structure of polysaccharide moiety of MTW was elucidated based on monosaccharide composition, methylation analysis, partial acid hydrolysis, IR and 1D/2D NMR spectroscopy. The results showed that MTW was a homogeneous glycopeptide including mannose and glucose with a molar ratio of 2:1...
February 7, 2017: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/28187785/longevity-and-gender-as-the-risk-factors-of-methicillin-resistant-staphylococcus-aureus-infections-in-southern-poland
#17
Monika Pomorska-Wesołowska, Anna Różańska, Joanna Natkaniec, Barbara Gryglewska, Anna Szczypta, Mirosława Dzikowska, Agnieszka Chmielarczyk, Jadwiga Wójkowska-Mach
BACKGROUND: The proportion of older people among the general population has risen. Staphylococcus aureus (SA) constitutes a significant problem. Underlying disease and functional debility, predispose the older adult to staphylococcal carriage and infection, specially bloodstream infection and pneumonia. METHODS: This is a retrospective cohort study of older patients with SA infections. We analyzed a database containing the results of laboratory cultures from patients treated in 2013 for SA infections and selected 613 hospitalized and non-hospitalized people aged ≥60 years...
February 10, 2017: BMC Geriatrics
https://www.readbyqxmd.com/read/28177454/drawglycan-snfg-a-robust-tool-to-render-glycans-and-glycopeptides-with-fragmentation-information
#18
Kai Cheng, Yusen Zhou, Sriram Neelamegham
No abstract text is available yet for this article.
March 15, 2017: Glycobiology
https://www.readbyqxmd.com/read/28169190/galactosylation-and-sialylation-levels-of-igg-predict-relapse-in-patients-with-pr3-anca-associated-vasculitis
#19
Michael J Kemna, Rosina Plomp, Pieter van Paassen, Carolien A M Koeleman, Bas C Jansen, Jan G M C Damoiseaux, Jan Willem Cohen Tervaert, Manfred Wuhrer
OBJECTIVE: The objective of our study is to investigate the Fc glycosylation profiles of both antigen-specific IgG targeted against proteinase 3 (PR3-ANCA) and total IgG as prognostic markers of relapse in patients with Granulomatosis with Polyangiitis (GPA). METHODS: Seventy-five patients with GPA and a PR3-ANCA rise during follow-up were included, of whom 43 patients relapsed within a median period of 8 (2-16) months. The N-glycan at Asn297 of affinity-purified and denatured total IgG and PR3-ANCA was determined by mass spectrometry of glycopeptides in samples obtained at the time of the PR3-ANCA rise and at the time of the relapse or time-matched during remission...
January 28, 2017: EBioMedicine
https://www.readbyqxmd.com/read/28144040/lipophilic-teicoplanin-pseudoaglycon-derivatives-are-active-against-vancomycin-and-teicoplanin-resistant-enterococci
#20
Zsolt Szűcs, Ilona Bereczki, Magdolna Csávás, Erzsébet Rőth, Anikó Borbás, Gyula Batta, Eszter Ostorházi, Réka Szatmári, Pál Herczegh
A selection of nine derivatives of teicoplanin pseudoaglycon were tested in vitro against clinical vancomycin-resistant Enterococcus strains possessing vanA, vanB or both genes. The bacteria were characterized by PCR for the identification of their resistance genes. The tested compounds contain lipoic acid, different carbohydrates and aryl groups as lipophilic moieties. About one-third of the teicoplanin-resistant strains were shown to be susceptible to one or more of the glycopeptide derivatives.The Journal of Antibiotics advance online publication, 1 February 2017; doi:10...
February 1, 2017: Journal of Antibiotics
keyword
keyword
117882
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"