Conformational changes of elongation factor G on the ribosome during tRNA translocation.
Cell
; 160(1-2): 219-27, 2015 Jan 15.
Article
in En
| MEDLINE
| ID: mdl-25594181
ABSTRACT
The universally conserved GTPase elongation factor G (EF-G) catalyzes the translocation of tRNA and mRNA on the ribosome after peptide bond formation. Despite numerous studies suggesting that EF-G undergoes extensive conformational rearrangements during translocation, high-resolution structures exist for essentially only one conformation of EF-G in complex with the ribosome. Here, we report four atomic-resolution crystal structures of EF-G bound to the ribosome programmed in the pre- and posttranslocational states and to the ribosome trapped by the antibiotic dityromycin. We observe a previously unseen conformation of EF-G in the pretranslocation complex, which is independently captured by dityromycin on the ribosome. Our structures provide insights into the conformational space that EF-G samples on the ribosome and reveal that tRNA translocation on the ribosome is facilitated by a structural transition of EF-G from a compact to an elongated conformation, which can be prevented by the antibiotic dityromycin.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Ribosomes
/
RNA, Transfer
/
Thermus thermophilus
/
Peptide Elongation Factor G
Type of study:
Prognostic_studies
Language:
En
Journal:
Cell
Year:
2015
Type:
Article
Affiliation country:
United States