2AKI

Normal mode-based flexible fitted coordinates of a translocating SecYEG protein-conducting channel into the cryo-EM map of a SecYEG-nascent chain-70S ribosome complex from E. coli


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 14.9 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of the E. coli protein-conducting channel bound to a translating ribosome.

Mitra, K.Schaffitzel, C.Shaikh, T.Tama, F.Jenni, S.Brooks, C.L.Ban, N.Frank, J.

(2005) Nature 438: 318-324

  • DOI: 10.1038/nature04133
  • Primary Citation of Related Structures:  2AKH

  • PubMed Abstract: 
  • Secreted and membrane proteins are translocated across or into cell membranes through a protein-conducting channel (PCC). Here we present a cryo-electron microscopy reconstruction of the Escherichia coli PCC, SecYEG, complexed with the ribosome and a ...

    Secreted and membrane proteins are translocated across or into cell membranes through a protein-conducting channel (PCC). Here we present a cryo-electron microscopy reconstruction of the Escherichia coli PCC, SecYEG, complexed with the ribosome and a nascent chain containing a signal anchor. This reconstruction shows a messenger RNA, three transfer RNAs, the nascent chain, and detailed features of both a translocating PCC and a second, non-translocating PCC bound to mRNA hairpins. The translocating PCC forms connections with ribosomal RNA hairpins on two sides and ribosomal proteins at the back, leaving a frontal opening. Normal mode-based flexible fitting of the archaeal SecYEbeta structure into the PCC electron microscopy densities favours a front-to-front arrangement of two SecYEG complexes in the PCC, and supports channel formation by the opening of two linked SecY halves during polypeptide translocation. On the basis of our observation in the translocating PCC of two segregated pores with different degrees of access to bulk lipid, we propose a model for co-translational protein translocation.


    Organizational Affiliation

    Howard Hughes Medical Institute, Health Research Inc. at the Wadsworth Center, Empire State Plaza, Albany, New York 12201-0509, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Protein-export membrane protein secG
X, A
77Escherichia coli (strain K12)Gene Names: secG
Find proteins for P0AG99 (Escherichia coli (strain K12))
Go to UniProtKB:  P0AG99
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Preprotein translocase secY subunit
Y, B
400Escherichia coli (strain K12)Gene Names: secY (prlA)
Find proteins for P0AGA2 (Escherichia coli (strain K12))
Go to UniProtKB:  P0AGA2
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Preprotein translocase secE subunit
Z, C
111Escherichia coli (strain K12)Gene Names: secE (prlG)
Find proteins for P0AG96 (Escherichia coli (strain K12))
Go to UniProtKB:  P0AG96
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 14.9 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-11-15
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance