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The structure of the ribosome with elongation factor G trapped in the posttranslocational state.

ABSTRACT: Elongation factor G (EF-G) is a guanosine triphosphatase (GTPase) that plays a crucial role in the translocation of transfer RNAs (tRNAs) and messenger RNA (mRNA) during translation by the ribosome. We report a crystal structure refined to 3.6 angstrom resolution of the ribosome trapped with EF-G in the posttranslocational state using the antibiotic fusidic acid. Fusidic acid traps EF-G in a conformation intermediate between the guanosine triphosphate and guanosine diphosphate forms. The interaction of EF-G with ribosomal elements implicated in stimulating catalysis, such as the L10-L12 stalk and the L11 region, and of domain IV of EF-G with the tRNA at the peptidyl-tRNA binding site (P site) and with mRNA shed light on the role of these elements in EF-G function. The stabilization of the mobile stalks of the ribosome also results in a more complete description of its structure.

SUBMITTER: Gao YG

PROVIDER: S-EPMC3763468 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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The structure of the ribosome with elongation factor G trapped in the posttranslocational state.

Gao Yong-Gui YG Selmer Maria M Dunham Christine M CM Weixlbaumer Albert A Kelley Ann C AC Ramakrishnan V V

Science (New York, N.Y.) 20091001 5953

Elongation factor G (EF-G) is a guanosine triphosphatase (GTPase) that plays a crucial role in the translocation of transfer RNAs (tRNAs) and messenger RNA (mRNA) during translation by the ribosome. We report a crystal structure refined to 3.6 angstrom resolution of the ribosome trapped with EF-G in the posttranslocational state using the antibiotic fusidic acid. Fusidic acid traps EF-G in a conformation intermediate between the guanosine triphosphate and guanosine diphosphate forms. The interac ...[more]

PMID: 19833919

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