Neoglycolipids as Glycosphingolipid Surrogates for Protein Binding Studies Using Nanodiscs and Native Mass Spectrometry.
Anal Chem
; 92(20): 14189-14196, 2020 10 20.
Article
em En
| MEDLINE
| ID: mdl-32940034
ABSTRACT
Interactions between glycan-binding proteins (GBPs) and glycosphingolipids (GSLs) in the membranes of cells are implicated in a wide variety of normal and pathophysiological processes. Despite the critical biological roles these interactions play, the GSL ligands of most GBPs have not yet been identified. The limited availability of purified GSLs represents a significant challenge to the discovery and characterization of biologically relevant GBP-GSL interactions. The present work investigates the use of neoglycolipids (NGLs) as surrogates for GSLs for catch-and-release-electrospray ionization mass spectrometry (CaR-ESI-MS)-based screening, implemented with nanodiscs, for the discovery of GSL ligands. Three pairs of NGLs based on the blood group type A and B trisaccharides, with three different lipid head groups but all with "ring-closed" monosaccharide residue at the reducing end, were synthesized. The incorporation efficiencies (into nanodiscs) of the NGLs and their affinities for a fragment of family 51 carbohydrate-binding module (CBM) identified an amide-linked 1,3-di-O-hexadecyl-glycerol moiety as the optimal lipid structure. Binding measurements performed on cholera toxin B subunit homopentamer (CTB5) and nanodiscs containing an NGL consisting of the optimal lipid moiety and the GM1 ganglioside pentasaccharide yielded affinities similar, within a factor of 2, to those of native GM1. Finally, nanodiscs containing the optimal A and B trisaccharide NGLs, as well as the corresponding NGLs of lactose, A type 2 tetrasaccharide, and the GM1 and GD2 pentasaccharides were screened against the family 51 CBM, human galectin-7, and CTB5 to illustrate the potential of NGLs to accelerate the discovery of GSL ligands of GBPs.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Polissacarídeos
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Glicoesfingolipídeos
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Proteínas
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Espectrometria de Massas por Ionização por Electrospray
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Nanoestruturas
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Bibliotecas de Moléculas Pequenas
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article