Importance of GSL Structure Analysis

GSLs are bound lipids composed of ceramides and oligosaccharide chains and are common components of eukaryotic plasma membranes. GSL plays an important role in cell recognition and communication, especially in the nervous system. The structure and function of GLS are closely related. The use of new modern analysis techniques to develop the structural analysis methodology of GLS and realize the qualitative characterization of GLS is an important guarantee for an in-depth understanding of the biological functions of GLS. It is also an important guarantee for clarifying the relationship between GLS structure changes and disease development and treatment. In recent years, with the development of modern instrumental analysis techniques, the analysis methods of GLS have made great progress.

Fig.1 Structural analysis of GSL using NMR spectroscopy. (Knaack, et al., 2021)

GSL Structure Analysis by ¹H,¹³C-Heteronuclear Multiple-Correlation Bond (HMBC) at CD BioGlyco

Since NMR is not limited by reference substances, and the use of multi-dimensional NMR technology can achieve accurate characterization of unknown compounds, it plays an irreplaceable role in the structural analysis of GLS, especially the characterization of newly discovered glycolipids.

CD Bioglyco, which has a large number of professional scientists, provides ¹H,¹³C-HMBC analysis as one of the means to analyze the structure of GSL by NMR.

Fig.2 Three types of correlation peaks in the HMBC spectrum. (CD BioGlyco)

There may be three types of correlation peaks in the HMBC spectrum:

• Reflecting the related peaks of long-range coupling between carbon atoms and hydrogen atoms. Such correlation peaks are easy to identify and are isolated peaks. This shows that the carbon atom and the hydrogen atom have a long-range coupling relationship. JCH coupling is most easily reflected with the usual parameter settings. It may also reflect CH and 4TCH coupling, but the intensity is generally lower.
• 2 A pair of peaks appear in the horizontal direction in the HMBC spectrum, and its center is aligned with a peak group in the hydrogen spectrum. The horizontal line crosses a line in the carbon spectrum, indicating that the hydrogen and carbon atoms involved are directly connected.
• 3 It is similar to the second point, except that there is another peak in the middle of that pair of peaks, and this peak is facing the center of the hydrogen spectrum peak group. This also reflects the one-bond correlation between hydrogen atoms and carbon atoms.

Advantages of Us

• HMBC has a relatively high resolution, and it associates ¹H nuclei with remote-coupled ¹³C nuclei. Usually, the protons with 2 or 3 bonds have more coupling information with carbon.
• HMBC is adjusted with a smaller coupling constant of 2JCH or 3JCH, and the carbon-hydrogen correlation spectrum separated by 2 or 3 bonds can be obtained.
• When the unknown structure contains quaternary carbons or heteroatoms, only HMBC can solve the relevant structural problems.
• Comprehensive and reliable after-sales service

At CD BioGlyco, we will work with our customers to define specific requirements and expectations to meet the partnership objectives. Our professional research teams provide customers with high-quality Carbohydrate Separation, Purification and Analysis services according to your needs. Our experienced staff will provide you with advanced ¹H,¹³C-HMBC technology to help you analyze the GSL structure. If you are interested in our services, please contact us for more details without any hesitation.

Reference

1. Knaack, W.; et al. Structural analysis of glycosylglycerolipids using NMR spectroscopy. Plant Lipids: Methods and Protocols. New York, NY. Springer US. 2021, 249-272.