Read by QxMD icon Read


Mijoon Lee, Dusan Hesek, Jaroslav Zajíček, Jed F Fisher, Shahriar Mobashery
The repeating isoprene unit is a fundamental biosynthetic motif. The repetitive structure presents challenges both for synthesis and for structural characterization. In this synthesis of the (Z8,E2,ω)-undecaprenol of prokaryotic glycobiology, we exemplify solutions to these challenges. Allylation of sulfone-derived carbanions controlled the stereochemistry, and its proof-of-structure was secured by Eu(hfc)3 complexation to disperse the overlaid resonances of its (1)H NMR spectrum.
November 15, 2017: Chemical Communications: Chem Comm
Cássia R A Cunha, Camila G Andrade, Maria I A Pereira, Paulo E Cabral Filho, Luiz B Carvalho, Luana C B B Coelho, Beate S Santos, Adriana Fontes, Maria T S Correia
The optical properties of quantum dots (QDs) make them useful tools for biology, especially when combined with biomolecules such as lectins. QDs conjugated to lectins can be used as nanoprobes for carbohydrate expression analysis, which can provide valuable information about glycosylation changes related to cancer and pathogenicity of microorganisms, for example. In this study, we evaluated the best strategy to conjugate Cramoll lectin to QDs and used the fluorescent labeling of Candida albicans cells as a proof-of-concept...
October 25, 2017: Journal of Photochemistry and Photobiology. B, Biology
C R A Cunha, A D P R Oliveira, T V C Firmino, D P L A Tenório, G Pereira, L B Carvalho, B S Santos, M T S Correia, A Fontes
BACKGROUND: Quantum dots (QDs) are outstanding nanomaterials of great interest to life sciences. Their conjugation versatility added to unique optical properties, highlight these nanocrystals as very promising fluorescent probes. Among uncountable new nanosystems, in the last years, QDs conjugated to glycans or lectins have aroused a growing attention and their application as a tool to study biological and functional properties has increased. SCOPE OF REVIEW: This review describes the strategies, reported in the literature, to conjugate QDs to lectins or carbohydrates, providing valuable information for the elaboration, improvement, and application of these nanoconjugates...
November 7, 2017: Biochimica et Biophysica Acta
Toshisuke Kawasaki, Robert K Yu
No abstract text is available yet for this article.
November 6, 2017: Glycoconjugate Journal
Roman R Kapaev, Philip V Toukach
Motivation: Carbohydrates play crucial roles in various biochemical processes and are useful for developing drugs and vaccines. However, in case of carbohydrates, the primary structure elucidation is usually a sophisticated task. Therefore, they remain the least structurally characterized class of biomolecules, and it hampers the progress in glycochemistry and glycobiology. Creating a usable instrument designed to assist researchers in natural carbohydrate structure determination would advance glycochemistry in biomedical and pharmaceutical applications...
October 28, 2017: Bioinformatics
Zhengwei Chen, Matthew S Glover, Lingjun Li
Glycans and glycoconjugates are involved in regulating a vast array of cellular and molecular processes. Despite the importance of glycans in biology and disease, characterization of glycans remains difficult due to their structural complexity and diversity. Mass spectrometry (MS)-based techniques have emerged as the premier analytical tools for characterizing glycans. However, traditional MS-based strategies struggle to distinguish the large number of coexisting isomeric glycans that are indistinguishable by mass alone...
October 25, 2017: Current Opinion in Chemical Biology
Sandip Pasari, Sujit Manmode, Gulab Walke, Srinivas Hotha
Oligosaccharides are involved in myriad of biological phenomena. Many glycobiological experiments can be undertaken if homogenous and well defined oligosaccharides are accessible. Mycobacterial cell wall contains arabinogalactan as one of the major constituents that is challenging for the chemical synthesis. Therefore, the major aim of this investigation is to synthesize a major oligosaccharide portion of the arabinogalactan. The pentacosafuranoside (25mer) synthesis involved installation of several arabinofuranosidic linkages through the neighbouring group participation for 1, 2-trans linkages and oxidation-reduction method for the 1, 2-cis Araf respectively...
October 26, 2017: Chemistry: a European Journal
Christian T Hjuler, Nicolai N Maolanon, Jørgen Sauer, Jens Stougaard, Mikkel B Thygesen, Knud J Jensen
Glycobiology, in particular the study of carbohydrate-protein interactions and the events that follow, has become an important research focus in recent decades. To study these interactions, many assays require homogeneous glycoconjugates in suitable amounts. Their synthesis is one of the methodological challenges of glycobiology. Here, we describe a versatile, three-stage protocol for the formation of glycoconjugates from unprotected carbohydrates, including those purified from natural sources, as exemplified here by rhizobial Nod factors and exopolysaccharide fragments...
November 2017: Nature Protocols
Victoria Dimakos, Graham E Garrett, Mark S Taylor
Site-selective functionalization of hydroxy groups in sugar derivatives is a major challenge in carbohydrate synthesis. Methods for achieving this goal will provide efficient access to new sugar-derived chemical building blocks and will facilitate the preparation or late-stage modification of complex oligosaccharides for applications in glycobiology research and drug discovery. Here, we describe site-selective, copper-promoted couplings of boronic acids with carbohydrate derivatives. These reactions generate sugar-derived aryl ethers, a structural class that is challenging to generate by other means and has not previously been accessed in a site-selective fashion...
November 1, 2017: Journal of the American Chemical Society
Zachary Klamer, Ben Staal, Anthony R Prudden, Lin Liu, David F Smith, Geert-Jan Boons, Brian Haab
Knowledge of lectin and glycosidase specificities is fundamental to the study of glycobiology. The primary specificities of such molecules can be uncovered using well-established tools, but the complex details of their specificities are difficult to determine and describe. Here we present a language and algorithm for the analysis and description of glycan motifs with high complexity. The language uses human-readable notation and wildcards, modifiers, and logical operators to define motifs of nearly any complexity...
November 3, 2017: Analytical Chemistry
(no author information available yet)
No abstract text is available yet for this article.
December 1, 2017: Glycobiology
Satoru Horiya, Jennifer K Bailey, Isaac J Krauss
Directed evolution is a useful method for the discovery of nucleic acids, peptides, or proteins that have desired binding abilities or functions. Because of the abundance and importance of glycosylation in nature, directed evolution of glycopeptides and glycoproteins is also highly desirable. However, common directed evolution platforms such as phage-, yeast-, or mammalian-cell display are limited for these applications by several factors. Glycan structure at each glycosylation site is not genetically encoded, and yeast and mammalian cells produce a heterogeneous mixture of glycoforms at each site on the protein...
2017: Methods in Enzymology
David H Kwan
Directed evolution is an incredibly powerful strategy for engineering enzyme function. Applying this approach to glycosidases offers enormous potential for the development of highly specialized tools in chemical glycobiology. Performing enzyme directed evolution requires the generation, by random mutagenesis, of mutant libraries from which large numbers of variant enzymes must be screened in high-throughput assays. A structure-guided "semirational" method for library creation allows researchers to target specific amino acid positions for mutagenesis, concentrating mutations where they might be most effective in order to produce mutant libraries of a manageable size, minimizing screening effort while maximizing the chances of finding improved mutants...
2017: Methods in Enzymology
Martin Rejzek, Lionel Hill, Edward S Hems, Sakonwan Kuhaudomlarp, Ben A Wagstaff, Robert A Field
Sugar nucleotides are essential building blocks for the glycobiology of all living organisms. Detailed information on the types of sugar nucleotides present in a particular cell and how they change as a function of metabolic, developmental, or disease status is vital. The extraction, identification, and quantification of sugar nucleotides in a given sample present formidable challenges. In this chapter, currently used techniques for sugar nucleotide extraction from cells, separation from complex biological matrices, and detection by optical and mass spectrometry methods are discussed...
2017: Methods in Enzymology
Madhur D Shastri, Gregory M Peterson, Rahul P Patel
Heparin is widely used as an anticoagulant. Currently, this macromolecule is at the forefront in the field of glycobiology because of the recognition of its therapeutic potential in a wide range of medical conditions including inflammation. Heparin is composed of anticoagulant and non-anticoagulant molecules. A large body of evidence suggests that the anti-inflammatory activities of heparin are attributed to its non-anticoagulant molecules and are therefore independent to its anticoagulant effect. However, the potential therapeutic use of heparin in inflammatory conditions is hindered by the presence of anticoagulant molecules causing the risk of bleeding...
October 2017: Current Allergy and Asthma Reports
Ronald L Schnaar, Yuan C Lee
Sialic acids have a special place in vertebrate glycobiology, where they constitute the dominant terminal saccharides on many cell surface glycans. From early studies that identified sialoglycans as receptors for important pathogens and toxins to more recent discoveries of sialic acid-binding proteins essential for immune system (and other) functions in humans, sialic acids and sialoglycans have become cornerstones in understanding vertebrate glycobiology and pathology. During a remarkable 3-year period in the late 1950s, a newly minted postdoctoral fellow (Donald G...
June 1, 2017: Glycobiology
Jingqian Jiang, Gerd K Wagner
Many glycosyltransferase inhibitors in the literature are structurally derived from the donor or acceptor substrate of the respective enzyme. A representative example is 2-naphthyl β-d-GlcNAc, a synthetic GlcNAc glycoside that has been reported as a galactosyltransferase inhibitor. This GlcNAc derivative is attractive as a chemical tool compound for biological and biochemical studies because of its reported potency as an inhibitor, and its short and straightforward synthesis from readily available starting materials...
October 10, 2017: Carbohydrate Research
Oier Aizpurua-Olaizola, Javier Sastre Torano, Aliaksei Pukin, Ou Fu, Geert Jan Boons, Gerhardus J de Jong, Roland J Pieters
Developing tools for the study of protein carbohydrate interactions is an important goal in glycobiology. Cholera toxin inhibition is an interesting target in this context, as its inhibition may help the fight against cholera. For the study of novel ligands an affinity capillary electrophoresis (ACE) method was optimised and applied. The method uses unlabeled cholera toxin B-subunit (CTB) and unlabeled carbohydrate ligands based on ganglioside GM1-oligosaccharides (GM1os). In an optimized method at pH 4, adsorption of the protein to the capillary walls was prevented by a polybrene-dextran sulfate-polybrene (PB-DS-PB) coating...
September 14, 2017: Electrophoresis
Onn Haji Hashim, Jaime Jacqueline Jayapalan, Cheng-Siang Lee
In recent years, the use of lectins for screening of potential biomarkers has gained increased importance in cancer research, given the development in glycobiology that highlights altered structural changes of glycans in cancer associated processes. Lectins, having the properties of recognizing specific carbohydrate moieties of glycoconjugates, have become an effective tool for detection of new cancer biomarkers in complex bodily fluids and tissues. The specificity of lectins provides an added advantage of selecting peptides that are differently glycosylated and aberrantly expressed in cancer patients, many of which are not possibly detected using conventional methods because of their low abundance in bodily fluids...
2017: PeerJ
Asher Williams, Wenqin He, Brady F Cress, Xinyue Liu, Jordanne Alexandria, Hiroki Yoshizawa, Kazuhiro Nishimura, Toshihiko Toida, Mattheos Koffas, Robert J Linhardt
Chondroitin sulfates are the glycosaminoglycan chains of proteoglycans critical in the normal development and pathophysiology of all animals. Chondroitinase ACII, a polysaccharide lyase originally isolated from Arthrobacter aurescens IAM 110 65, which is widely used in the analysis and study of chondroitin structure, is no longer commercially available. The aim of the current study is to prepare recombinant versions of this critical enzyme for the glycobiology research community. Two versions of recombinant chondroitinase ACII are prepared in Escherichia coli, and their activity, stability, specificity, and action pattern are examined, along with a non-recombinant version secreted by an Arthrobacter strain...
August 11, 2017: Biotechnology Journal
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"