The structural basis of protein targeting and translocation in bacteria.
In Gram-negative bacteria, two distinct targeting routes assist in the proper localization of secreted and membrane proteins. Signal recognition particle (SRP) mainly targets ribosome-bound nascent membrane proteins, whereas SecB facilitates the targeting of periplasmic and outer membrane proteins. These routes converge at the translocase, a protein-conducting pore in the membrane that consists of the SecYEG complex associated with the peripheral ATPase, SecA. Recent structural studies of the targeting and the translocating components provide insights into how substrates are recognized and suggest a mechanism by which proteins are transported through an aqueous pore in the cytoplasmic membrane.
Driessen
A J
AJ
Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Kerklaan 30, 9751 NN Haren, The Netherlands.
Manting
E H
EH
van der Does
C
C
D000251:Adenosine Triphosphatases / Q000378:metabolism; D001419:Bacteria / Q000166:cytology / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism; D018360:Crystallography, X-Ray; D029968:Escherichia coli Proteins; D026901:Membrane Transport Proteins; D008958:Models, Molecular; D011487:Protein Conformation; D011498:Protein Precursors / Q000378:metabolism; D021381:Protein Transport; D012270:Ribosomes / Q000378:metabolism; D000069816:SEC Translocation Channels; D000081416:SecA Proteins; D018271:Signal Recognition Particle / Q000378:metabolism*
D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D026901:Membrane Transport Proteins; D011498:Protein Precursors; D000069816:SEC Translocation Channels; C057842:SecB protein, Bacteria; D018271:Signal Recognition Particle; D000251:Adenosine Triphosphatases; D000081416:SecA Proteins