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Chemoenzymatic Fc glycosylation via engineered aldehyde tags.

ABSTRACT: Glycoproteins with chemically defined glycosylation sites and structures are important biopharmaceutical targets and critical tools for glycobiology. One approach toward constructing such molecules involves chemical glycosylation of aldehyde-tagged proteins. Here, we report the installation of a genetically encoded aldehyde tag at the internal glycosylation site of the crystallizable fragment (Fc) of IgG1. We replaced the natural Fc N-glycosylation sequon with a five amino-acid sequence that was efficiently converted by recombinant formylglycine generating enzyme in vitro, thereby introducing aldehyde groups for subsequent chemical elaboration. Oxime-linked glycoconjugates were synthesized by conjugating aminooxy N-acetylglucosamine to the modified Fc followed by enzymatic transfer of complex N-glycans from corresponding glycan oxazolines by an EndoS-derived glycosynthase. In this manner we generated specific Fc glycoforms without relying on natural protein glycosylation machineries.

SUBMITTER: Smith EL

PROVIDER: S-EPMC4004622 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

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Chemoenzymatic Fc glycosylation via engineered aldehyde tags.

Smith Elizabeth L EL Giddens John P JP Iavarone Anthony T AT Godula Kamil K Wang Lai-Xi LX Bertozzi Carolyn R CR

Bioconjugate chemistry 20140407 4

Glycoproteins with chemically defined glycosylation sites and structures are important biopharmaceutical targets and critical tools for glycobiology. One approach toward constructing such molecules involves chemical glycosylation of aldehyde-tagged proteins. Here, we report the installation of a genetically encoded aldehyde tag at the internal glycosylation site of the crystallizable fragment (Fc) of IgG1. We replaced the natural Fc N-glycosylation sequon with a five amino-acid sequence that was ...[more]

PMID: 24702330

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