Manual and Automated Syntheses of the N-Linked Glycoprotein Core Glycans.
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ABSTRACT:
SUBMITTER: Pistorio SG
PROVIDER: S-EPMC8114088 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:N-glycosylation is a fundamental modification of proteins and exists in the three domains of life and in some viruses, including the chloroviruses, for which a new type of core N-glycan is herein described. This N-glycan core structure, common to all chloroviruses, is a pentasaccharide with a ?-glucose linked to an asparagine residue which is not located in the typical sequon N-X-T/S. The glucose is linked to a terminal xylose unit and a hyperbranched fucose, which is in turn substituted with a terminal galactose and a second xylose residue. The third position of the fucose unit is always linked to a rhamnose, which is a semiconserved element because its absolute configuration is virus-dependent. Additional decorations occur on this core N-glycan and represent a molecular signature for each chlorovirus.
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Project description:Exoglycosidases are often used for detailed characterization of glycan structures. Bovine kidney ?-fucosidase is commonly used to determine the presence of core ?1-6 fucose on N-glycans, an important modification of glycoproteins. Recently, several studies have reported that removal of core ?1-6-linked fucose from N-glycans labeled with the reactive N-hydroxysuccinimide carbamate fluorescent labels 6-aminoquinolyl-N-hydroxysuccinimidylcarbamate (AQC) and RapiFluor-MS is severely impeded. We report here the cloning, expression and biochemical characterization of an ?-fucosidase from Omnitrophica bacterium (termed fucosidase O). We show that fucosidase O can efficiently remove ?1-6- and ?1-3-linked core fucose from N-glycans. Additionally, we demonstrate that fucosidase O is able to efficiently hydrolyze core ?1-6-linked fucose from N-glycans labeled with any of the existing NHS-carbamate activated fluorescent dyes.
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