title: Site-specific chemical modification of a glycoprotein fragment expressed in yeast.
abstract: Site-specific modification of glycoproteins has wide application in both biochemical and biophysical studies. This method describes the conjugation of synthetic molecules to the N-terminus of a glycoprotein fragment, viz., human immunoglobulin G subclass 1 fragment crystallizable (IgG1 Fc), by native chemical ligation. The glycosylated IgG1 Fc is expressed in a glycosylation-deficient yeast strain. The N-terminal cysteine is generated by the endogenous yeast protease Kex2 in the yeast secretory pathway. The N-terminal cysteine is then conjugated with a biotin thioester to produce a biotinylated, glycosylated IgG1 Fc using native chemical ligation.
authors.forename: Junpeng
authors.initials: J
authors.lastname: Xiao
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Tolbert
mesh_terms: D000085:Acetates / Q000138:chemical synthesis / Q000737:chemistry; D001665:Binding Sites; D019921:Biotinylation; D015870:Gene Expression; D006023:Glycoproteins / Q000737:chemistry*; D006031:Glycosylation; D006801:Humans; D007141:Immunoglobulin Fc Fragments / Q000737:chemistry* / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D007074:Immunoglobulin G / Q000737:chemistry*; D010957:Plasmids / Q000235:genetics; D043484:Proprotein Convertases / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D000085:Acetates; D006023:Glycoproteins; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D029701:Saccharomyces cerevisiae Proteins; D043484:Proprotein Convertases; C058751:KEX2 protein, S cerevisiae