Recent developments in glycobiology have shown the importance of glycoproteins and their derived glycopeptides in immunologicals processes, tissue differentiation, function of protein ligands and receptors, infectious agents and many other biological processes. Therefore, there is a need for a supply of these compounds to satisfy the needs of the researchers. Glycosylation, the process of adding carbohydrate residues to a polypeptide, is an enzymatic process that readily occurs at the asparagine, serine and/or threonine residues. Yet, glycosylation of these residues by synthetic methods is not easy to achieve.
It has become evident is that the nature of the link between the amino acid residue and the sugar as well as the nature of the amino acid itself is not crucial for the functions of the glycosylated product. What appears to be important is the nature of the oligosaccharide chain and in some cases its location in a polypeptide chain. Based on these findings a new kind of bioconjugates of carbohydrates linked to proteins or peptides has been developed, called neoglycoproteins or neoglycopeptides respectively. The amino acids of choice to substitute the asparagine, serine or threonine residues are lysine and cysteine. The reasons for selecting these amino acids being their available functional groups, amino and thiol correspondingly, which readily react with a number of well identified activated linkers. Other alternative sites in polypeptides available for glycosylation are the terminal amino and carboxyl groups. The possibility of selecting the size of the linker chain may allow the optimization of the conditions for recognition of the carbohydrate moieties by certain receptors.
For instance, studies concerning fertilization had shown that neoglycoproteins built using serum albumin as the required backbone can be used to identify the oligosaccharides responsible for initiating key events during this process. A similar approach using serum albumin as a scaffold for the oligosaccharides had been used to identify the cell receptors for some infectious agents, e.g. Porphyromonas gingivalis and Toxoplasma gondii. In general neoglycoproteins are largely used to identify or study the roles of the sugar moieties.
Recent advances in peptide synthesis can allow the preparation of authentic neoglycopeptides by using glycosylated amino acids as building blocks, thus avoiding the need to express the protein in a cell system. Applications of neoglycopeptides can be found in the targeting and translocation of oligonucleotides. The sugar moiety would be responsible for targeting specific cells, while the peptide would carry out the translocation of the oligonucleotides. Thus, neoglycopeptides offer new avenues for diverse areas of research. Bio-Synthesis has been producing synthetic peptides for over 25 years. Our expertise in custom synthetic polypeptide manufacturing allows us to produce the high-quality, large-scale, and GMP peptides with the highest success rate with long standing records. We have been delivered more than 100,000 peptides to customers worldwide, including very hydrophobic polypeptide, peptide with multiple disulfide bonds, multi-phosph0rylated peptides and extremely long peptides. Our large scale non-GMP ever delivered 5 kilograms of peptides on a single order and has the capacity of 10,000 peptides per month. Our capacity of GMP peptide is 10 kilograms.
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