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Making Conjugation-induced Fluorescent PEGylated Virus-like Particles by Dibromomaleimide-disulfide Chemistry
Published on: May 27, 2018
Effect of Calcium Ions and Disulfide Bonds on Swelling of Virus Particles
Roi Asor1,1, Daniel Khaykelson1,1, Orly Ben-Nun-Shaul2
1Institute of Chemistry and Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel.
Abstract:
Multivalent ions affect the structure and organization of virus nanoparticles. Wild-type simian virus 40 (wt SV40) is a nonenveloped virus belonging to the polyomavirus family, whose external diameter is 48.4 nm. Calcium ions and disulfide bonds are involved in the stabilization of its capsid and are playing a role in its assembly and disassembly pathways. Using solution small-angle X-ray scattering (SAXS), we found that the volume of wt SV40 swelled by about 17% when both of its calcium ions were chelated by ethylene glycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid and its disulfide bonds were reduced by dithiothreitol. By applying osmotic stress, the swelling could be reversed. DNA-containing virus-like particles behaved in a similar way. The results provide insight into the structural role of calcium ions and disulfide bonds in holding the capsid proteins in compact conformation.
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