The Structure of the Potato Virus A Particles Elucidated by Small Angle X-Ray Scattering and Complementary Techniques

Potato virus A (PVA) protein coat contains on its surface partially unstructured N-terminal domain of the viral (CP), whose structural and functional characteristics are important for understanding mechanism plant infection with this virus. In work, we investigated properties structure intact PVA trypsinized PVAΔ32 virions using small-angle X-ray scattering (SAXS) complimentary methods. It was shown that after removal 32 amino acids CP, virion did not disintegrate remained compact, but helical pitch CP packing changed. To determine nature these changes, performed ab initio modeling, including multiphase procedure, geometric bodies (helices) restoration in solution available high-resolution structures homologous from PVY potyvirus, based SAXS data. As a result, first time, low-resolution filamentous virus, both degraded, elucidated under conditions close to natural. The far-UV circular dichroism spectra samples differed significantly amplitude position main negative maximum. extent thermal denaturation temperature range 20-55°C also different. data transmission electron microscopy showed were mostly rod-shaped, contrast flexible particles typical which correlated well results. general, analysis indicates an importance vital functions PVA, can be used develop strategy combating pathogen.