Bioorthogonal Surface Modification of Measles and Vaccinia Viruses Using Metabolic Azide Reporters

Area of Science:

• Virology
• Cell Biology
• Biochemistry

Background:

• Enveloped viruses like measles virus (MV) and vaccinia virus (VACV) obtain lipid bilayers from host cell membranes during assembly.
• Host cell membranes can be chemically modified for selective labeling and visualization of viral components.

Purpose of the Study:

• To detail a metabolic labeling strategy for visualizing enveloped viruses using bioorthogonal chemistry.
• To enable fluorescent labeling and tracking of viral particles for live-cell imaging and trafficking studies.

Main Methods:

• Supplementation of Vero cells with peracetylated azido sugars (Ac4GalNAz, Ac4ManNAz) and azido-choline analogs (AECho).
• Incorporation of bioorthogonal metabolic reporters into host and viral membranes, creating azide-functionalized glycoconjugates and phosphatidylcholine (PC) derivatives.
• Conjugation of surface-exposed azido groups on progeny virions with fluorescent probes via SPAAC or CuAAC reactions.

Main Results:

• Successful incorporation of azide-functionalized reporters into both host cell and viral membranes.
• Demonstration of fluorescent labeling of progeny virions through click chemistry reactions.
• Enabling direct visualization of viral particles using fluorescence microscopy.

Conclusions:

• The described metabolic labeling strategy provides a versatile platform for studying enveloped viruses.
• This method facilitates live-cell imaging, viral trafficking analysis, and the development of targeted delivery systems.