Neo-glycoprotein Conjugates
Neo-glycoproteins and neo-glycopeptides, also known as neo-glycoconjugates, are synthetic glycoconjugates. They differ from naturally occurring glycoproteins in that they are not based on native linkages, and they may incorporate non-natural or altered glycan structures thereby creating novel molecules with specific properties. Neo-glycoproteins are chemically synthesized by reacting complementary functional groups on the glycan with those on the protein backbone. For example, glycans can be equipped with reactive handles such as activated esters or maleimides that can be chemo-selectively coupled to available amine groups on lysine residues or thiols on cysteines, respectively. Alternatively, glycans can be coupled to proteins using click chemistry approaches by reacting biorthogonal complementary functional groups such as azides and alkynes. Neo-glycoproteins exhibit diverse properties based on their glycan composition and valency compared to natural glycoproteins. They have been used for a variety of diagnostic and therapeutic applications including vaccine development, drug delivery, and glycan arrays.
We can provide neo-glycoproteins with a wide range of glycans (natural and non-natural) conjugated to proteins including bovine serum albumin (BSA), keyhole limpet hemocyanin (KLH), and others. The glycans can be coupled to the protein using a variety of chemistries including amine reactive, thiol reactive, and click-chemistry.
BSA
Glycosaminoglycans (GAGs) are a diverse group of linear glycans composed of repeating disaccharide units. The disaccharide consists of an amino sugar such as glucosamine (GlcN) (that is N-acetylated (GlcNAc) or N-sulfated (GlcNS)) or N-acetylgalactosamine (GalNAc) and a uronic acid such as glucuronic acid (GlcA) or iduronic acid (IdoA), or galactose (Gal). GAGs are an essential component of the extracellular matrix and connective tissues, where they play critical roles in maintaining tissue hydration, elasticity, and structural integrity. GAGs are classified into several distinct families based on their disaccharide composition and sulfation patterns:
Hyaluronan – Unlike other GAGs, hyaluronan is non-sulfated and has a simple disaccharide structure consisting of glucuronic acid and N-acetylglucosamine. Hyaluronan does not occur covalently linked to a protein core. It is a major component of synovial fluid, vitreous humor, and connective tissues, contributing to tissue hydration and lubrication.
Chondroitin Sulfate – Composed of repeating disaccharide units of glucuronic acid and N-acetylgalactosamine, which can be sulfated at various positions. They are predominantly found in cartilage, bone, and skin, where they provide mechanical support and resilience.
Dermatan Sulfate – Characterized by repeating disaccharide units of iduronic acid and N-acetylgalactosamine, this GAG is found in skin, tendons, and heart valves. It plays a role in wound healing and tissue repair.
Heparin and Heparan Sulfate – These GAGs have repeating disaccharide units of glucuronic acid (or iduronic acid) and glucosamine. Heparin is known for its potent anticoagulant properties, while heparan sulfate is involved in cell signaling and growth factor regulation.
Keratan Sulfate – Composed of sulfated repeating disaccharide units of galactose and N-acetylglucosamine (poly-N-acetyllactosamine). Keratan sulfate is primarily found in the cornea, cartilage, and bone, where it contributes to tissue transparency and strength.
GAGs are crucial for many physiological processes, and abnormalities in their metabolism or function can lead to a range of diseases. For example, mucopolysaccharidoses (MPS) are a group of inherited lysosomal storage diseases (LSDs) caused by deficiencies in specific enzymes responsible for the degradation of GAGs. This leads to the accumulation of GAGs in lysosomes and other tissues. MPS diseases are classified based on the specific enzyme deficiency and the type of GAGs that accumulate.
We have a wide portfolio of synthetic, well-defined, and highly pure GAG disaccharide and tetrasaccharide structures including reducing sugars. These compounds can be used as authentic samples or diagnostic standards for degradation products in projects developing therapeutics for GAG related lysosomal storage diseases. Focused libraries of GAG structures can also be provided.
