Glycosylated peptides

Glycosylation of peptides is an efficient method to stabilize peptide by inhibition of enzymatic degradation, to conformationally modify peptide and usually to increase peptide solubility. Peptides glycosylation also creates additional diversity in peptide libraries since the high functionalities and variability of sugar moieties. 

Suzuki, T., Park, H., Kitajima, K., and Lennarz, W. J. (1998). Peptides glycosylated in the endoplasmic reticulum of yeast are subsequently deglycosylated by a soluble peptide A-glycanase activity. J. Biol. Chem. 273, 21526-21530. 

One glycosylation site exists on the P suburhts of human LH [53664-53-2 and TSH [64365-92-OJ ie, Asn-30 (Fig. 4). In some species, Asn-13 of LH-P is glycosylated (48). FSH-P suburnt [58857-12-8] is glycosylated at two sites, Asn-13 and 30. Based on interactions of synthetic peptides with the LH receptor, loops formed by P93—100 and P38—57 may be essential for hormone bioactivity (48). Highly conserved sequences between residues 31—37 have been implicated in the formation of the a—P suburnt dimer (48), which is absolutely necessary for the expression of bioactivity. 

This active ester was used for carboxyl protection of Fmoc-serine and Fmoc-threonine during glycosylation. The esters are then used as active esters in peptide synthesis. 

Phosphate esters and anhydrides dominate the living world. Major areas of synthetic interest include oligonucleotides (polymeric phosphate diesters), phospho-rylated peptides, phospholipids, glycosyl phosphates, and inositol phosphates. ... 

Rituximab is a recombinant mouse/human chimeric monoclonal antibody whose in vitro activity varies with the number of terminal galactose moieties glycosylated to the peptide backbone at residue asparagine 301 [8]. The ability to monitor the levels of each discrete species present would allow the manufacturing process to... 

---