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Updated: Jan 7, 2026
07:53
A Fluorogenic Peptide Cleavage Assay to Screen for Proteolytic Activity: Applications for coronavirus spike protein activation
Published on: January 9, 2019
33.7K
Protease-Mediated Shedding and Intermittent Mobility of the SARS-CoV-2 Delta Variant
Manorama Dey1, Poojitha Sai Potharaju2, Khushika3
1Department of Chemistry, Indian Institute of Technology Kanpur, 208016 Kanpur, India.
The Journal of Physical Chemistry Letters
|December 26, 2025
Summary
Soluble serine proteases detach SARS-CoV-2 from membranes, with the Delta variant showing the fastest shedding and unique mobility. This protease-mediated shedding impacts viral dynamics and membrane interactions.
Area of Science:
- Virology
- Biophysics
- Membrane Biology
Background:
- Soluble serine proteases can interact with viral particles.
- Understanding virus-membrane interactions is crucial for virology.
- The shedding mechanism of SARS-CoV-2 from lipid membranes requires further investigation.
Purpose of the Study:
- To investigate the role of soluble serine proteases in SARS-CoV-2 detachment from lipid membranes.
- To compare the shedding kinetics of different SARS-CoV-2 variants.
- To elucidate the diffusion dynamics of membrane-bound SARS-CoV-2 variants.
Main Methods:
- Fluorescence imaging of labeled SARS-CoV-2 particles on native membrane mimics.
- Surface Plasmon Resonance (SPR) for kinetic analysis.
- Single-particle tracking to evaluate particle diffusion and mobility.
Main Results:
- Soluble serine proteases (trypsin, chymotrypsin) trigger SARS-CoV-2 shedding from lipid membranes.
- The Delta variant exhibits the fastest shedding kinetics, followed by B.1.1.8 and Omicron variants.
- Protease treatment induces lateral mobility in membrane-bound Delta variants, unlike other variants, leading to non-Gaussian diffusion.
Conclusions:
- Soluble serine proteases play a significant role in releasing SARS-CoV-2 from membrane surfaces.
- The Delta variant's distinct shedding and mobility dynamics suggest unique interactions with host membranes.
- A 'hopping motion' model explains the Delta variant's behavior due to dynamic membrane binding and protease activity.
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