EMD-2705

Single-particle
8.0 Å
EMD-2705 Deposition: 10/07/2014
Map released: 23/07/2014
Last modified: 27/08/2014
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-2705

A structural model of the active ribosome-bound membrane protein insertase YidC

EMD-2705

Single-particle
8.0 Å
EMD-2705 Deposition: 10/07/2014
Map released: 23/07/2014
Last modified: 27/08/2014
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Escherichia coli
Sample: Monomeric YidC bound to ribosome nascent chain complex(F0c)
Fitted models: 4utq (Avg. Q-score: 0.107)

Deposition Authors: Wickles S, Singharoy A, Andreani J , Seemayer S , Bischoff L, Berninghausen O, Soeding J, Schulten K, van der Sluis EO, Beckmann R
A structural model of the active ribosome-bound membrane protein insertase YidC
Abstract:
The integration of most membrane proteins into the cytoplasmic membrane of bacteria occurs co-translationally. The universally conserved YidC protein mediates this process either individually as a membrane protein insertase, or in concert with the SecY complex. Here, we present a structural model of YidC based on evolutionary co-variation analysis, lipid-versus-protein-exposure and molecular dynamics simulations. The model suggests a distinctive arrangement of the conserved five transmembrane domains and a helical hairpin between transmembrane segment 2 (TM2) and TM3 on the cytoplasmic membrane surface. The model was used for docking into a cryo-electron microscopy reconstruction of a translating YidC-ribosome complex carrying the YidC substrate FOc. This structure reveals how a single copy of YidC interacts with the ribosome at the ribosomal tunnel exit and identifies a site for membrane protein insertion at the YidC protein-lipid interface. Together, these data suggest a mechanism for the co-translational mode of YidC-mediated membrane protein insertion.