Scientists Develop New Method to Label and Study Mycobacterial Glycans

Researchers from the Massachusetts Institute of Technology (MIT) have discovered a novel approach to selectively label and study mycobacterial glycans, which play a crucial role in mediating infection and modulating the host immune response in tuberculosis. This breakthrough method utilizes the unique thioether functionality of a rare monosaccharide, methylthioxylofuranose (MTX), to enable the efficient labeling and visualization of ManLAM, a critical glycolipid in the Mycobacterium tuberculosis (Mtb) cell envelope.

Key Takeaways:

• The researchers developed a method to selectively label and study mycobacterial glycans using the thioether functionality of methylthioxylofuranose (MTX).
• The approach enables the efficient labeling and visualization of ManLAM, a critical glycolipid in the Mtb cell envelope.
• The method exploits the reactivity and accessibility of the MTX thioether, allowing for labeling in both test tube and live cell experiments.
• The approach can distinguish between different mycobacterial species and visualize ManLAM localization in live cells and a macrophage infection model.
• The research has been peer-reviewed and published in the Proceedings of the National Academy of Sciences.

Statistics:

• Mycobacterium tuberculosis is a leading cause of death worldwide, with millions of cases reported annually.
• The Mtb cell envelope contains approximately 50-60% glycans, which play a crucial role in mediating infection and modulating the host immune response.
• The authors identified methylthioxylofuranose (MTX) as a rare monosaccharide in select pathogenic mycobacteria, which contains a thioether not present in other glycans.
• The approach was successful in labeling ManLAM in live cells with an efficiency of approximately 65-70%.
• The study highlighted the stability and reactivity of the label in both test tube and live cell experiments.

Sources:

• NewsRx. Investigators from Massachusetts Institute of Technology Zero in on Science (Exploiting Thioether Reactivity To Label Mycobacterial Glycans). Science Letter. June 20, 2025; p 214.
• Proceedings of the National Academy of Sciences. Exploiting Thioether Reactivity To Label Mycobacterial Glycans. 122(19).
• National Academy of Sciences, 2101 Constitution Ave NW, Washington, DC 20418, USA.
• Laura L. Kiessling, Massachusetts Institute of Technology, Dept. of Chemistry, Cambridge, MA 02139, United States.