THE THERMAL-STABILITY OF TURNIP YELLOW MOSAIC-VIRUS UNDER HYDROSTATIC-PRESSURE - A SMALL-ANGLE NEUTRON-SCATTERING STUDY

Abstract

The thermal stability of an isometric plant virus, Turnip Yellow Mosaic Virus (TYMV), has been investigated at low and high hydrostatic pressure, using small angle neutron scattering. Contrast variation allowed us to separately observe the structural changes of the protein capsid and the RNA core. The experiments were performed in 0.05 M Tris buffer at pD = 8.0 and in 0.05 M bis-Tris buffer at pD = 6.0 containing different H2O/D2O mixtures (40% and 70% D2O). It was found that hydrostatic pressure enhances the stability of TYMV. The thermally induced uncoating of RNA as well as structural transitions of the protein capsid are shifted to higher temperature upon increasing the pressure from 5 x 10(6) Pa to 2 x 10(8) Pa.