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The structure of an elongation factor G-ribosome complex captured in the absence of inhibitors.

ABSTRACT: During translation's elongation cycle, elongation factor G (EF-G) promotes messenger and transfer RNA translocation through the ribosome. Until now, the structures reported for EF-G-ribosome complexes have been obtained by trapping EF-G in the ribosome. These results were based on use of non-hydrolyzable guanosine 5'-triphosphate (GTP) analogs, specific inhibitors or a mutated EF-G form. Here, we present the first cryo-electron microscopy structure of EF-G bound to ribosome in the absence of an inhibitor. The structure reveals a natural conformation of EF-G·GDP in the ribosome, with a previously unseen conformation of its third domain. These data show how EF-G must affect translocation, and suggest the molecular mechanism by which fusidic acid antibiotic prevents the release of EF-G after GTP hydrolysis.

SUBMITTER: Mace K

PROVIDER: S-EPMC5887593 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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The structure of an elongation factor G-ribosome complex captured in the absence of inhibitors.

Macé Kevin K Giudice Emmanuel E Chat Sophie S Gillet Reynald R

Nucleic acids research 20180401 6

During translation's elongation cycle, elongation factor G (EF-G) promotes messenger and transfer RNA translocation through the ribosome. Until now, the structures reported for EF-G-ribosome complexes have been obtained by trapping EF-G in the ribosome. These results were based on use of non-hydrolyzable guanosine 5'-triphosphate (GTP) analogs, specific inhibitors or a mutated EF-G form. Here, we present the first cryo-electron microscopy structure of EF-G bound to ribosome in the absence of an ...[more]

PMID: 29408956

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