Aminated complex-type sugar chain derivatives and process for the production thereof
An aminated complex-type oligosaccharide derivative of the formula (1) wherein R 1 is H—(CO)—CH 2 X, —NH—(CO)—(CH 2 ) b —CH 2 X, isothiocyanate group, —NH—(CO) a —(CH 2 ) b —CO 2 H or —NH—(CO) a —(CH 2 ) b —CHO, X being a halogen atom, a being 0 or 1, b being an integer of 1 to 4, R 2 and R 3 are a hydrogen atom or a group of the formulae (2) to (5) and may be the same or different, except for the case where both R 2 and R 3 are hydrogen or the formula (5), and the case where one of R 2 and R 3 is a hydrogen atom, with the formula (5) serving as the other thereof.
1. A glycopeptide comprising an aminated complex-type oligosaccharide of the formula (1)
wherein R 1 is —NH—(CO)—CH 2 X, X being a halogen atom, R 2 and R 3 are a hydrogen atom or a group of the formulae (2) to (5) and may be the same or different, except that R 2 and R 3 are not both hydrogen or the formula (5) at the same time and when one of R2 and R3 is hydrogen, the other is not the formula (5),
and the aminated complex-type oligosaccharide is bound to a thiol group of a peptide by displacement of halogen X of NH—(CO)—CH 2 X further wherein the glycopeptide has about 12 times higher resistance to Peptide-N Glycosidase F (PNGase F) than the glycopeptide comprising said aminated complex-type oligosaccharide of formula (1), wherein R1 is an asparagine.
2. A glycopeptide as defined in claim 1 wherein the glycopeptide is an antibody.
3. A process for preparing a uniform glycopeptide composition comprising steps of (a) and (b) that are performed at the same time,
(a) cleaving an asparagine-linked oligosaccharide of a glycopeptide from a peptide by Peptide-N Glycosidase F (PNGase F), wherein the resulting peptide has a thiol group, and
(b) bonding an aminated complex-type oligosaccharide of the formula (1)
wherein R 1 is —NH—(CO)—CH 2 X, X being a halogen atom, R 2 and R 3 are a hydrogen atom or a group of the formulae (2) to (5) and may be the same or different, except that R 2 and R 3 are not both hydrogen or the formula (5) at the same time and when on of R2 and R3 is hydrogen, the other is not the formula (5),
to the thiol group of the resulting peptide by displacement of halogen X of —NH—(CO)—CH 2 X.