CD BioGlyco is committed to the study of the structure, biosynthesis, and biological functions of sugars (sugar chains or glycans) widely distributed in nature. With advanced technology and dedicated scientists, we have been recognized by scientists from many countries. We sincerely hope to cooperate with you and help with your scientific research work.

Structure of Human Milk Oligosaccharides (HMOs)

HMO is a unique and complex mixture, composed of five monosaccharides glucose (Glc), galactose (Gal), N-acetylglucosamine (GlcNAc), fucose (Fuc), and sialic acid linked by different glycosidic bonds. To date, more than 200 highly complex HMOs have been identified. These HMOs are divided into tetra to decaose core structures, including at least 13 core structures. All HMOs contain a lactose structure at the reducing end, which can be further fucosylated or sialylated. Therefore, HMOs are classified as fucosylated oligosaccharides, sialylated or acidic oligosaccharides, and non-fucosylated neutral oligosaccharides.

Fig.1 Neutral non-fucosylated HMO, fucosylated HMO, and sialylated HMO. (Faijes, et al., 2019)

Features of Lacto-N-triose II (LNT II)

LNT II is a neutral non-fucosylated oligosaccharide with a structure of GlcNAcβ1-3Galβ1-4Glc. It is produced by the β1,3-acetylglucosaminyltransferase (Lgt A)-catalyzed reaction of GlcNAc and β-lactose substrate. As an important precursor, LNT II can be used to synthesize lactose-N-neotetraose (LNnT, Galβ1-4GlcNAcβ1-3Galβ1-4Glc), lactose-N-tetraose (LNT, Galβ1-3GlcNAcβ1-3Galβ1-4Glc), and other HMO skeletons. LNnT and LNT are also important core structures of HMOs, which can be further subjected to fucosylation or sialylation to generate other HMOs. Therefore, the large-scale production of LNT II has attracted increasing attention.

Fig.2 Chemical structure of LNT II. (CD BioGlyco)

At present, the commonly used methods of HMO synthesis include chemical synthesis, enzymatic method, and cell factory method. Traditional chemical synthesis involves multiple reaction steps such as activation, protection, glycosylation, and deprotection, and the yield is low, which is not suitable for the industrial production of LNT II. The enzymatic synthesis of LNT II is catalyzed by glycosyltransferase and glycosidase. For example, β-N-acetylhexosaminidase catalyzes the transfer of GlcNAc from various β-N-acetylhexosamine donors to β-lactose via transglycosylation to produce LNT II.

LNT II Analysis Service at CD BioGlyco

Due to the different connection positions and types of monosaccharide structural units, the structure of HMOs is diverse. Comprehensive strategies are needed for the detailed analysis of HMOs. Mass spectrometry (MS) provides a new strategy of HMO analysis. CD BioGlyco combines MS with analytical techniques such as High-Performance Liquid Chromatography (HPLC) and ion chromatography (IC) to analyze LNT II in complex samples. This combined technique has the advantages of rapidity, high accuracy, and good reproducibility.

In addition, we also provide diverse HMO products for global clients, including but not limited to:

Advantages of Us

• The coupling of techniques such as LC and CE to MS
• Rapidity, high accuracy, and good reproducibility
• LNT II analysis in complex samples
• Professional technical team

To analyze the composition of HMOs in samples and characterize their structure, CD BioGlyco has developed a high-quality HMO Profiling solution. We provide fast and accurate HMO analysis services for enterprises, universities and research institutes. If you are interested in our services, please feel free to contact us.

References:

1. Faijes, M.; et al. Enzymatic and cell factory approaches to the production of human milk oligosaccharides. Biotechnology advances. 2019, 37(5): 667-697.
2. Liu, Y.; et al. Production of lacto-N-triose II and lacto-N-neotetraose from chitin by a novel β-N-acetylhexosaminidase expressed in Pichia pastoris. ACS Sustainable Chemistry & Engineering. 2020, 8(41): 15466-15474.