Abstract
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.
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Acknowledgements
We would like to thank A. Mark and N. Nouwen for careful reading of the manuscript, and the past and present members of the team who contributed to this work. This work was supported by the Earth and Life Sciences Foundation (Algemene Levenswetenschappen, ALW), the Netherlands Foundation for Chemical Research (Chemische Wetenschappen, CW), and the Netherlands Foundation for Scientific Research (Nederlandse Wetenschappelijk Onderzoek, NWO).
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Driessen, A., Manting, E. & van der Does, C. The structural basis of protein targeting and translocation in bacteria. Nat Struct Mol Biol 8, 492–498 (2001). https://doi.org/10.1038/88549
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DOI: https://doi.org/10.1038/88549
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