Galβ1-4GlcNAcβ1-3Galβ1-4GlcNAcβ1-3Galβ1-4GlcNAc

Galβ1-4GlcNAcβ1-3Galβ1-4GlcNAcβ1-3Galβ1-4GlcNAc (pentasaccharide poly-LacNAc type 2 chain) forms a linear, repeating N-acetyllactosamine backbone critical for cell adhesion, immune recognition, and tumor metastasis research, appearing as a white lyophilized powder used in glycan microarray standards and selectin ligand studies. This i-antigen precursor (also called VIM-2 pentasaccharide) features three sequential β1-4Gal-GlcNAcβ1-3 disaccharides on a reducing GlcNAc terminus, serving as high-affinity E-selectin/P-selectin ligand for leukocyte rolling during inflammation while binding macrophage galectin-3 for tumor immune evasion; commercially synthesized via β4GalT/β3GnT cascades (>97% purity), it demonstrates gastric stability, selective enzymatic extension to sialyl-Lewis structures, and roles in cancer glycomimetics, stem cell differentiation markers, and anti-metastatic drug screening, with ambient shelf stability exceeding 48 months.

Appearance

• White amorphous lyophilized powder, odorless and non-hygroscopic.
• Freely water-soluble (>400 g/L); clear solutions pH 6-8.​

Source

• Abundant in human poly-LacNAc chains on leukocytes, erythrocytes (adult i-antigen).
• Enzymatic synthesis using alternating β1-4 galactosyl/β1-3 N-acetylglucosaminyl transferases.​

Molecular Weight and Structure

• 1100.98 g/mol (sodium form), formula C₄₂H₇₁N₃O₃₁.
• [Galβ1-4GlcNAcβ1-3]₃Galβ1-4GlcNAc linear repeating type 2 chain.​

Sugar Specificity

• Binds E-selectin, P-selectin, siglec-3/5 via poly-LacNAc backbone.
• Substrates for α2-3/6 sialyltransferases, α1-3 fucosyltransferases (sLeX formation).​

Biological Activity

• Mediates leukocyte extravasation; galectin-3 ligand for tumor metastasis.
• Prebiotic for Bacteroides promoting butyrate production; anti-inflammatory.​

Purity and Microbial Contamination

• ≥97% anomeric HPLC/NMR; endotoxins <2 EU/mg.
• Sterile filtered; heavy metals <0.5 ppm, moisture <3%.​

Identity and Quality Control

• ¹H-NMR confirms β-linkages (Gal H1 4.4-4.6 ppm); LC-MS [M+2Na]²⁺ 572.
• HPAEC monosaccharide ratio Gal:GlcNAc 3:2; linkage analysis.​

Shelf Life and Storage

• 48+ months ambient desiccated; 5+ years -20°C lyophilized.
• Avoid extreme pH (>9) or hydrolases.​

Applications

• Selectin inhibitor screening; cancer glycan biomarkers.
• Stem cell surface marker research; glycoengineering scaffolds.​

Key Characteristics

• Linear scaffold for glycan extension; high selectin avidity.
• Type 2 chain specificity vs branched type 1; gastric-stable.​

Citation Links

• https://pubchem.ncbi.nlm.nih.gov/compound/71297720​
• https://pubchem.ncbi.nlm.nih.gov/compound/172642668​
• https://alpha.glycosmos.org/organisms/10066/glycans​
• https://www.sciencedirect.com/science/article/pii/S0021925819367900​
• https://academic.oup.com/glycob/article-pdf/13/5/387/1648069/cwg044.pdf​
• https://oro.open.ac.uk/38117/1/c1sc00120e.pdf​
• https://pubchem.ncbi.nlm.nih.gov/compound/156613025​
• https://mcawdb.glycoinfo.org/detail.html?296​
• https://glycosmos.org/structure/poly-LacNAc​