Conformational Changes in Polyampholyte Macrochains on the Surface of an Oblate Metallic Nanospheroid in Alternating Electric Field
N. Yu. Kruchinin, М. Г. Кучеренко
Abstract
Conformational changes in polyampholyte polypeptides adsorbed on the surface of an oblate metal nanospheroid with a periodic change in time of its polarity along the axis of rotation have been studied using the molecular dynamics method. The radial distributions of polypeptide atoms, as well as the distributions of the linear density of polypeptide atoms along the nanospheroid rotation axis, are constructed. The obtained conformational structures of polyampholytes were compared in the presence and in the absence of sodium and chlorine ions in water. At low temperatures, the formation of a narrow macromolecular ring around the nanospheroid near the equator was observed; the ring swelled with an increase in the amplitude of an external alternating electric field; and polyampholyte desorption occurred with a further increase in the amplitude. At high temperatures, periodic changes in the conformational structure of adsorbed polyampholytic polypeptides were observed on the surface of the oblate metal nanospheroid with the frequency of an external polarizing alternating field.