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Updated: Jul 9, 2026

In Vitro Disassembly of Influenza A Virus Capsids by Gradient Centrifugation
Published on: March 27, 2016
Sphingomyelin induces structural alteration in canine parvovirus capsid
Kirsi Pakkanen1, Jenni Karttunen, Salla Virtanen
1Department of Biological and Environmental Science, University of Jyväskylä, Finland. kiinpakk@bytl.jyu.fi
Canine parvovirus (CPV) capsid structural changes occur with sphingomyelin, but this interaction does not affect the virus's phospholipase A(2) (PLA(2)) activity. These findings suggest alternative CPV capsid and sphingomyelin interactions during infection.
Area of Science:
- Virology
- Biochemistry
- Molecular Biology
Background:
- Canine parvovirus (CPV) infection involves virus capsid interactions with endosomal membranes for release.
- The VP1 unique N-terminus of CPV possesses phospholipase A(2) (PLA(2)) activity crucial for infection.
Purpose of the Study:
- To investigate the impact of sphingomyelin and phosphatidyl serine on CPV capsid structure.
- To determine the effect of these lipids on the PLA(2) enzymatic activity of the CPV VP1 N-terminus.
Main Methods:
- Tryptophan fluorescence spectroscopy to detect changes in CPV capsid structure.
- Circular dichroism (CD) spectroscopy to analyze structural alterations.
- Enzymatic assays to measure CPV PLA(2) activity in the presence of lipids.
Main Results:
- Sphingomyelin induced a significant shift in tryptophan fluorescence emission at acidic pH (5.5), indicating structural changes in the CPV capsid.
- CD spectroscopy confirmed structural differences in the CPV capsid upon interaction with sphingomyelin and phosphatidyl serine.
- No significant alteration in CPV PLA(2) enzymatic activity was observed in the presence of sphingomyelin.
Conclusions:
- Spectroscopic data reveal structural interactions between CPV capsid and sphingomyelin, particularly at acidic pH.
- These structural changes do not influence the enzymatic activity of CPV PLA(2).
- The findings suggest alternative mechanisms of interaction between CPV capsid and sphingomyelin, independent of PLA(2) activity.
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