Magnesium Contact Ions Stabilize the Tertiary Structure of Transfer RNA: Electrostatics Mapped by Two-Dimensional Infrared Spectra and Theoretical Simulations.

ABSTRACT: Ions interacting with hydrated RNA play a central role in defining its secondary and tertiary structure. While spatial arrangements of ions, water molecules, and phosphate groups have been inferred from X-ray studies, the role of electrostatic and other noncovalent interactions in stabilizing compact folded RNA structures is not fully understood at the molecular level. Here, we demonstrate that contact ion pairs of magnesium (Mg²⁺) and phosphate groups embedded in local water shells stabilize the tertiary equilibrium structure of transfer RNA (tRNA). Employing dialyzed tRNA^Phe from yeast and tRNA from Escherichia coli, we follow the population of Mg²⁺ sites close to phosphate groups of the ribose-phosphodiester backbone step by step, combining linear

SUBMITTER: Schauss J 

PROVIDER: S-EPMC7848891 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature