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Domain motions of EF-G bound to the 70S ribosome: insights from a hand-shaking between multi-resolution structures.

ABSTRACT: Molecular modeling and information processing techniques were combined to refine the structure of translocase (EF-G) in the ribosome-bound form against data from cryoelectron microscopy (cryo-EM). We devised a novel multi-scale refinement method based on vector quantization and force-field methods that gives excellent agreement between the flexibly docked structure of GDP. EF-G and the cryo-EM density map at 17 A resolution. The refinement reveals a dramatic "induced fit" conformational change on the 70S ribosome, mainly involving EF-G's domains III, IV, and V. The rearrangement of EF-G's structurally preserved regions, mediated and guided by flexible linkers, defines the site of interaction with the GTPase-associated center of the ribosome.

SUBMITTER: Wriggers W

PROVIDER: S-EPMC1301058 | biostudies-other | 2000 Sep

REPOSITORIES: biostudies-other

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Domain motions of EF-G bound to the 70S ribosome: insights from a hand-shaking between multi-resolution structures.

Wriggers W W Agrawal R K RK Drew D L DL McCammon A A Frank J J

Biophysical journal 20000901 3

Molecular modeling and information processing techniques were combined to refine the structure of translocase (EF-G) in the ribosome-bound form against data from cryoelectron microscopy (cryo-EM). We devised a novel multi-scale refinement method based on vector quantization and force-field methods that gives excellent agreement between the flexibly docked structure of GDP. EF-G and the cryo-EM density map at 17 A resolution. The refinement reveals a dramatic "induced fit" conformational change o ...[more]

PMID: 10969026

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