EMD-2705
A structural model of the active ribosome-bound membrane protein insertase YidC
EMD-2705
Single-particle8.0 Å
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Map released: 23/07/2014
Last modified: 27/08/2014
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
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
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A structural model of the active ribosome-bound membrane protein insertase YidC
Wickles S,
Singharoy A,
Andreani J
,
Seemayer S
,
Bischoff L,
Berninghausen O,
Soeding J,
Schulten K,
van der Sluis EO,
Beckmann R
(2014) elife , 3 , e03035 - e03035
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(2014) elife , 3 , e03035 - e03035
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.
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.