ADP-ribosylated elongation factor 2 (ADP-ribosyl-EF-2) is unable to promote translocation within the ribosome

FEBS Lett. 1990 Feb 26;261(2):350-2. doi: 10.1016/0014-5793(90)80589-b.

Abstract

Elongation factor 2 (EF-2), ADP-ribosylated in vitro by the A-fragment of diphtheria toxin, can (in the presence of GMPPCP) form stable complexes with ribosomes regardless of whether the ribosomes are empty or carrying poly(U) and Phe-tRNA in the A-site. Despite its efficient binding to ribosomes, ADP-ribosyl-EF-2, in contrast to the non-modified EF-2 is unable to promote the shift of Phe-tRNA from the A-site to the P-site of the ribosome as determined by the puromycin reaction, i.e. it is incapable of promoting the translocation reaction within the ribosome.

MeSH terms

  • Adenosine Diphosphate Ribose / metabolism*
  • Animals
  • Binding, Competitive
  • Biological Transport
  • Diphtheria Toxin / metabolism
  • Guanosine Triphosphate / analogs & derivatives
  • Guanosine Triphosphate / pharmacology
  • Peptide Elongation Factor 2
  • Peptide Elongation Factors / metabolism*
  • Poly U / metabolism
  • Puromycin / metabolism
  • RNA, Transfer, Phe / metabolism
  • Rabbits
  • Ribosomes / metabolism*

Substances

  • Diphtheria Toxin
  • Peptide Elongation Factor 2
  • Peptide Elongation Factors
  • RNA, Transfer, Phe
  • Adenosine Diphosphate Ribose
  • Poly U
  • guanosine 5'-(beta,gamma-methylene)triphosphate
  • Puromycin
  • Guanosine Triphosphate