4URD

Cryo-EM map of Trigger Factor bound to a translating ribosome

Summary for 4URD

• Entry DOI: 10.2210/pdb4urd/pdb
• EMDB information: 2695
• Descriptor: TRIGGER FACTOR (1 entity in total)
• Functional Keywords: isomerase, translation, co-translational protein folding
• Biological source: ESCHERICHIA COLI
• Total number of polymer chains: 1
• Total formula weight: 12711.55

Authors

Deeng, J.,Chan, K.Y.,van der Sluis, E.,Bischoff, L.,Berninghausen, O.,Han, W.,Gumbart, J.,Schulten, K.,Beatrix, B.,Beckmann, R. (deposition date: 2014-06-27, release date: 2016-01-13, Last modification date: 2024-05-08)

Primary citation

Deeng, J.,Chan, K.Y.,Van Der Sluis, E.O.,Berninghausen, O.,Han, W.,Gumbart, J.,Schulten, K.,Beatrix, B.,Beckmann, R.
Dynamic Behavior of Trigger Factor on the Ribosome.
J.Mol.Biol., 428:3588-, 2016

PubMed Abstract: Trigger factor (TF) is the only ribosome-associated chaperone in bacteria. It interacts with hydrophobic segments in nascent chain (NCs) as they emerge from the ribosome. TF binds via its N-terminal ribosome-binding domain (RBD) mainly to ribosomal protein uL23 at the tunnel exit on the large ribosomal subunit. Whereas earlier structural data suggested that TF binds as a rigid molecule to the ribosome, recent comparisons of structural data on substrate-bound, ribosome-bound, and TF in solution from different species suggest that this chaperone is a rather flexible molecule. Here, we present two cryo-electron microscopy structures of TF bound to ribosomes translating an mRNA coding for a known TF substrate from Escherichia coli of a different length. The structures reveal distinct degrees of flexibility for the different TF domains, a conformational rearrangement of the RBD upon ribosome binding, and an increase in rigidity within TF when the NC is extended. Molecular dynamics simulations agree with these data and offer a molecular basis for these observations.

PubMed: 27320387
DOI: 10.1016/J.JMB.2016.06.007

Experimental method

ELECTRON MICROSCOPY (7.7 Å)