Glycosylated Peptide Synthesis

Glycopeptides are a class of molecules that are formed by the combination of carbohydrates (sugars) and peptides (short chains of amino acids). CD Formulation provides targeted and unique peptide glycosylation modification services for monosaccharides, disaccharides, and polysaccharides. We can also perform glycosylation modifications such as sialic acid and fucose on the main chain and side chain of the peptide.

The Importance of Peptide Glycosylation Modifications

Glycosylation is an important post-translational modification process that involves the attachment of carbohydrates (sugar chains) to proteins or peptides through covalent linkage. The normal glycosylation process is achieved through enzymatic reactions in the body, including glycosyltransferases. Glycosylation modification not only helps to regulate the physicochemical properties of proteins and peptides, such as solubility, stability, and conformational changes, but also affects their interactions with other molecules (such as receptors, ligands, etc.), thereby having an important impact on physiological processes such as cell signaling, immune response, and cell recognition. In recent years, the synthesis of glycosylated peptides has become an area that has received increasing attention in the development of biopharmaceuticals. By synthesizing glycosylated peptides, the biological functions of natural glycosylated proteins can be better simulated, thereby improving the effectiveness and specificity of drugs.

Fig. 1 Schematic diagram of glycopeptide chemical synthesis. (Doelman W, et al., 202)

Explore Our Custom Glycosylated Peptide Synthesis Services

As an expert in peptide modification, CD Formulation provides high-quality glycopeptide and glycosylated peptide synthesis services to customers worldwide. We develop glycosylated amino acids in Fmoc solid phase peptide synthesis (SPPS) using standard protocols and combine pre-synthesized glycosylated amino acids with SPPS to extend peptides.

Importantly, in glycopeptide synthesis, our scientists are adept at incorporating different forms of sugar chains into your custom peptides, at single or multiple positions, or together with other modifications. Our typical glycopeptide synthesis is 15-25 amino acids.

Glycopeptides that can be synthesized include:

N-Linked Glycopeptides

• A class of glycopeptides containing an N-glycosidic bond between the glycan and the Asp side chain.
• The sequence Asn-Xaa-Ser/Thr is the key feature of the site of N-glycosylation.
• The carbohydrate moiety has more variables, including α- and β-glucosamine, and β-N-acetylgalactosamine (GalNAc).

O-Linked Glycopeptides

• A type of glycopeptide that is linked to a sugar molecule through a hydroxyl group (usually a serine or threonine residue) with a glycosidic bond.
• The sugars that can be linked include α-galactose (Gal), glucose (Glc), fucose (Fuc), mannose (Man), and xylose (Xyl).
• O-GlcNAc modification is a separate category of O-linked glycosylation in which the monosaccharide is attached to Ser or Thr.

Our Glycosylated Peptide Synthesis Strategies

Total Chemical Synthesis

Total chemical synthesis involves the production of the entire molecule through organic transformation. In our peptide synthesis laboratory, the total chemical synthesis of O-glycosylated peptides usually adopts a building block-based approach, in which the entire glycosylated serine or threonine residue is first synthesized as a Fmoc-protected building block. These amino acids are then incorporated into the desired peptide sequence using standard Fmoc-SPPS conditions. Unlike the synthesis of O-glycosylated peptides, the synthesis of most N-glycosylated amino acids or peptides introduces the glycosidic bond between the amino acid and the oligosaccharide at a late stage of the synthesis, producing the key glycoside-asparagine bond.

Chemoenzymatic Synthesis

In the chemoenzymatic synthesis method, part of the synthesis is completed by enzymatic conversion. Our scientists can synthesize a variety of N/O-glycosylated peptides through enzymatic processing. The synthetic strategy is to first chemically synthesize a peptide containing α-GalNAc-Ser/Thr as a starting point for the enzymatic introduction of additional sugars, followed by enzymatic conversion of glycopeptide synthesis. Using this method, sialic acid can be stereoselectively introduced as well as more complex oligosaccharides into the peptide structure.

Synthesis Based on Conjugation Methods

In this method, the covalent attachment of peptides and oligosaccharides is achieved using one of a variety of chemical methods. The conjugation strategy is based on the unique reactivity of the amino acid cysteine and involves the use of organic transformations for glycoconjugation and metal-catalyzed attachment. These methods typically produce glycoconjugates containing one or more non-natural bonds.

Biosynthesis

This method relies on genetic engineering and cell factories, such as bacteria, yeast or mammalian cells, for production. Our scientists express the target glycosylated peptides in specific cells by introducing the corresponding genes and regulating the culture conditions to achieve the desired glycosylation pattern.

Available Glycosylated Amino Acid Options

Ser	Thr	Asn
Glucose
Ser(β-D-GlcNAc)	Thr(β-D-GlcNAc)	Asn(β-D-GlcNAc)
Ser(β-D-Glc)	Thr(β-D-Glc)	Asn(β-D-Glc)
Galactose
Ser(α-D-GalNAc)|(Tn Antigen)	Thr(α-D-GalNAc)
Ser(α-D-Gal)	Thr(α-D-Gal)
Ser(Gal β(1-3) GalNAc)|(TF Antigen)	Thr(Gal β(1-3) GalNAc)|(TF Antigen)
Ser(β-D-Gal)	Thr(β-D-Gal)
Mannose
Ser(α-D-Man)	Thr(α-D-Man)

Peptide Manufacturing & Analytical Services

In addition to peptide synthesis capabilities, CD Formulation combines flexible GMP manufacturing facilities with cutting-edge peptide analytical knowledge to provide a full range of quality control testing services to accelerate the commercialization of your products, including:

Publication

CD Formulation has extensive experience with each glycosylation modification of peptides. Please don't hesitate to contact us if you are interested in our services, and to learn more about the possibilities of incorporating glycosylated amino acid into your peptides. We look forward to cooperating with you.

How It Works

STEP 1

Submit a service request describing your specific research or development need.

STEP 2

We'll email you to provide your quote and confirm order details if applicable.

STEP 3

Execute the project with real-time communication, and deliver the final report promptly.