Fluorometric Estimation of Viral Thermal Stability.

Differential Scanning Fluorimetry (DSF) is a rapid, economical, and a straightforward technique for estimating the thermal stability of proteins. The principle involves the binding of a fluorescent dye to thermally exposed hydrophobic pockets of a protein. The dyes used in this technique are highly fluorescent in a non-polar environment and are quenched when exposed to aqueous solution.

Comparative analysis of adeno-associated virus capsid stability and dynamics.

Icosahedral viral capsids are obligated to perform a thermodynamic balancing act. Capsids must be stable enough to protect the genome until a suitable host cell is encountered yet be poised to bind receptor, initiate cell entry, navigate the cellular milieu, and release their genome in the appropriate replication compartment. In this study, serotypes of adeno-associated virus (AAV), AAV1, AAV2, AAV5, and AAV8, were compared with respect to the physical properties of their capsids that influence thermodynamic stability.

Thermodynamic characterization of viral procapsid expansion into a functional capsid shell.

The assembly of "complex" DNA viruses such as the herpesviruses and many tailed bacteriophages includes a DNA packaging step where the viral genome is inserted into a preformed procapsid shell. Packaging triggers a remarkable capsid expansion transition that results in thinning of the shell and an increase in capsid volume to accept the full-length genome. This transition is considered irreversible; however, here we demonstrate that the phage λ procapsid can be expanded with urea in vitro and that the transition is fully reversible.