New Methods for Chemo-Enzymatic Galactosidation of 2S Rapeseed Protein

作者：Andre Corinne; Niamke Sebastien; Faure Alice; Colas Bernard; Berot Serge; Larre Colette; Gueguen Jacques; Rabiller Claude^*

来源：Protein Journal, 2004, 23(4): 247-254.

DOI：10.1023/B:JOPC.0000027849.08211.85

• Chemo-enzymatic synthesis
• neoglycoproteins
• 6-oxogalactosides
• rapeseed 2S protein
• transglycosylation

Two chemo-enzymatic methodologies to synthesize neoglycoproteins from rapeseed 2S protein (napin) were developed. In the first approach, glycosidases were used to catalyse 1-O-glycosylation of serine residues, whereas in the second one, 6-N-galactosylation was examined using an amino-reduction reaction between the epsilon-NH(2) of lysine residues and 6-oxogalactosides (readily available by means of the oxidation reaction of the corresponding galactosides mediated by galactose oxidase). Our results indicated that glycosidases were unable to glycosylate native proteins. Conversely, this reaction was possible, although in low yields (10%), after the introduction of a hydroxyethylene spacer. The latter modified proteins were obtained via the condensation of epsilon-NH(2) of lysines with ethylene carbonate in basic medium (40% yield). The second approach was much more efficient, as 61% of the lysine residues were shown to be 6-N-galactosylated using sodium cyanoborohydride as a reduction reagent.

• 出版日期2004-5