Abstract
The translocatlon reaction catalyzed by elongation factor G (EF-G) is inhibited either by α-sarcin cleavage of 23S rRNA or by the binding of thiostrepton to the E. coli ribosome. Here we show that the transitory binding of EF-G and GDP to the ribosome inhibited the rate of α-sarcin cleavage and that stabilization of this binding with fusidic acid completely prevented α-sarcin cleavage. A similar pattern of inhibition was seen upon the binding of elongation factor 2 to the S. cerevisiae ribosome. The irreversible binding of the antibiotic thiostrepton to the E. coli ribosome, on the other hand, decreased the rate of cleavage by α-sarcin approximately 2-fold. These results suggest that the α-sarcin site is located within the ribosomal domain for EF-G binding and that the conformation of this site is affected by the binding of thiostrepton.
Original language | English (US) |
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Pages (from-to) | 1657-1660 |
Number of pages | 4 |
Journal | Nucleic acids research |
Volume | 19 |
Issue number | 7 |
DOIs | |
State | Published - Apr 11 1991 |
Bibliographical note
Funding Information:This work was supported by grant GM-26832 from the NIH.