Structural Insights into the Distortion of the Ribosomal Small Subunit at Different Magnesium Concentrations.

ABSTRACT: Magnesium ions are abundant and play indispensable functions in the ribosome. A decrease in Mg²⁺ concentration causes 70S ribosome dissociation and subsequent unfolding. Structural distortion at low Mg²⁺ concentrations has been observed in an immature pre50S, while the structural changes in mature subunits have not yet been studied. Here, we purified the 30S subunits of E. coli cells under various Mg²⁺ concentrations and analyzed their structural distortion by cryo-electron microscopy. Upon systematically interrogating the structural heterogeneity within the 1 mM Mg²⁺ dataset, we observed 30S particles with different levels of structural distortion in the decoding center, h17, and the 30S head. Our model showed that, when the Mg²⁺

SUBMITTER: Yu T 

PROVIDER: S-EPMC10046523 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature