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N-Linked Glycans of Chloroviruses Sharing a Core Architecture without Precedent.

ABSTRACT: 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.

SUBMITTER: De Castro C

PROVIDER: S-EPMC4836869 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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N-Linked Glycans of Chloroviruses Sharing a Core Architecture without Precedent.

De Castro Cristina C Speciale Immacolata I Duncan Garry G Dunigan David D DD Agarkova Irina I Lanzetta Rosa R Sturiale Luisa L Palmigiano Angelo A Garozzo Domenico D Molinaro Antonio A Tonetti Michela M Van Etten James L JL

Angewandte Chemie (International ed. in English) 20151119 2

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 β-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 ...[more]

PMID: 26582281

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