Tuesday, August 31, 2010
Bio Synthesis may use your oligosaccharides for preparation of the conjugates or in some cases it could prepare the whole conjugate, including the oligosaccharide moiety. For the preparation of oligopeptides and oligonucleotides glycoconjugates these compounds are modified during solid phase synthesis to introduce a spacer carrying a functional group that can be used for subsequent cross-linking with the oligosaccharides. Depending on the nature of the oligosaccharide and the peptide or oligonucleotide the length and hydrophilicity of the spacer would be decided to maximize the interactions of these compounds with their receptors.
Advances in glycobiology highlight the role of naturally occurring glycoconjugates in different biological processes. The most common glycoconjugates are those where an oligosaccharide is covalently linked to a protein, peptide or lipid, yet in some cases it can be also linked to an oligonucleotide. Synthetic conjugates are excellent tools to elucidate the natural glycoconjugates' roles in different biological processes. In these conjugates an oligosaccharide is usually cross-linked to a reporter group, such as a fluorochrome, enzyme, liposome, colloidal gold and others, that can be easily detected.
Other Useful Tools
Other useful tools in biological studies are those compounds where the oligosaccharide is coupled to a fluorescent label such as fluorescein, rhodamine, Texas red and others, either directly or via a spacer. Fluorescent compounds can be detected by fluorescence microscopy, FACS machine, and spectrofluorometry. Other tagging methods involve the use of colloidal gold and ferritin, both compounds that can be detected by electron microscopy. Oligosaccharides can also be conjugated to different lipids to yield glycolipids that can be incorporated into either micelles or liposomes, with the latter being effective drug carriers.
Glycoconjugates of Oligosaccharides
The same methods used to prepare glycoconjugates of oligosaccharides can be applied to native polysaccharides. Base on the needs for sensitivity, nature of the molecule recognizing the sugar moiety, Bio-Synthesis can design a method to label these macromolecules without interfering with their interactions with other molecules.