Coating of azobenzene chromophore with multivalent sugar ligands has been accomplished. Such sugar coating allows the study of the isomerization properties of this chromophore in aqueous solutions. The predominantly cis-isomer-containing photostationary state (PS) mixture of these azobenzene derivatives is found to be stable for hours. The rate constants for their isomerization, as well as the Arrhenius activation energies, are determined experimentally. An assessment of the lectin binding properties of the lactoside bearing isomeric azobenzene derivatives, by isothermal calorimetric methods, reveals the existence of an unusual cooperativity in their binding to lectin peanut agglutinin. Thermodynamic parameters evaluated for the trans and the PS mixture are discussed, in detail, for the lactoside bearing bivalent azobenzene derivative.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/ja0173066 | DOI Listing |
Carbohydr Res
February 2025
Faculty of Pharmacy and Pharmaceutical Sciences, Josai University, 1-1 Keyakidai, Sakado, Saitama, 350-0295, Japan. Electronic address:
We investigated the transglycosylation reaction of two types of oligosaccharide acceptors, i.e., β-cyclodextrin (CD) derivatives 1 and 2 conjugated with multiple glucose (Glc) units, catalyzed by endo-β-N-acetyl-glucosaminidase from Mucor hiemalis (Endo-M) using the oligosaccharide donor sialoglycopeptide (SGP).
View Article and Find Full Text PDFArch Biochem Biophys
December 2024
The Division of Structural Biology, The Nuffield Department of Medicine, University of Oxford, UK; The Rosalind Franklin Institute, Harwell Campus, Didcot, OX11 0QS, UK. Electronic address:
Multifunctionality, processivity, and thermostability are critical for the cost-effective enzymatic saccharification of non-food plant biomass polymers such as β-glucans, celluloses, and xylans to generate biofuels and other valuable products. We present molecular insights into a processive multifunctional endo-1,3-1,4-β-d-glucanase (Tt_End5A) from the hyperthermophilic bacterium Thermogutta terrifontis. Tt_End5A demonstrated activities against a broad spectrum of β-polysaccharides, including barley glucan, lichenan, carboxymethyl cellulose, regenerated amorphous cellulose (RAC), Avicel, xylan, laminarin, mannan, curdlan, xanthan, and various chromogenic substrates at pH 7 and temperatures ranging from 70 to 80°C.
View Article and Find Full Text PDFInorg Chem
December 2024
Departments of Chemistry, Molecular Biosciences, Neurobiology, and Radiology, Northwestern University, Evanston, Illinois 60208, United States.
Glycoconjugates forming from the conjugation of carbohydrates to other biomolecules, such as proteins, lipids, or other carbohydrates, are essential components of mammalian cells and are involved in numerous biological processes. Due to the capability of sugars to form multiple hydrogen bonds, many synthetic glycoconjugates are desirable biocompatible platforms for imaging, diagnostics, drugs, and supramolecular self-assemblies. Herein, we present a multimeric galactose functionalized paramagnetic gadolinium (Gd(III)) chelate that displays spontaneous dynamic aggregation in aqueous conditions.
View Article and Find Full Text PDFRSC Adv
November 2024
Department of Chemistry, Davidson College Davidson NC 28035 USA
The importance of lectins in biological processes such as pathogen recognition, cell adhesion, and cell recognition is well documented. C-Type lectins, which require calcium for binding, play an important role in the innate immune response by engaging carbohydrates presented as part of the human and pathogen glycocalyx. For example, lectins such as MBL, Dectin-2, langerin and DC-SIGN selectively recognize mannose rich (high-mannose) structures presented as part of the glycocalyx.
View Article and Find Full Text PDFJACS Au
November 2024
School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.
Carbohydrates play pivotal roles in the first stages of microbial infections and can be exploited as decoys to hijack the interactions between bacteria and the host cell. Multivalent glycan probes mimicking the natural presentation of glycans in living cells have been successfully employed to study fundamental carbohydrate/protein interactions in microbial systems; however, most pathogenic glycan receptors exhibit a shared specificity for commonly found sugars present in both healthy and pathogenic cells, posing a challenge for target selectivity. In this study, we report the synthesis of a small library of d-arabinose multivalent probes, a sugar absent in human physiology, and their evaluation in a bacteria agglutination assay using cluster analysis.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!