Correlated conformational events in EF-G and the ribosome regulate translocation Academic Article uri icon

Overview

MeSH Major

  • Escherichia coli
  • Peptide Elongation Factor G
  • Ribosomes

abstract

  • In bacteria, the translocation of tRNA and mRNA with respect to the ribosome is catalyzed by the conserved GTPase elongation factor-G (EF-G). To probe the rate-determining features in this process, we imaged EF-G-catalyzed translocation from two unique structural perspectives using single-molecule fluorescence resonance energy transfer. The data reveal that the rate at which the ribosome spontaneously achieves a transient, 'unlocked' state is closely correlated with the rate at which the tRNA-like domain IV-V element of EF-G engages the A site. After these structural transitions, translocation occurs comparatively fast, suggesting that conformational processes intrinsic to the ribosome determine the rate of translocation. Experiments conducted in the presence of non-hydrolyzable GTP analogs and specific antibiotics further reveal that allosterically linked conformational events in EF-G and the ribosome mediate rapid, directional substrate movement and EF-G release.

publication date

  • December 2010

Research

keywords

  • Academic Article

Identity

Language

  • eng

PubMed Central ID

  • PMC2997181

Digital Object Identifier (DOI)

  • 10.1038/nsmb.1925

PubMed ID

  • 21057527

Additional Document Info

start page

  • 1470

end page

  • 7

volume

  • 17

number

  • 12