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The structural basis of protein targeting and translocation in bacteria

Nature Structural Biology volume 8, pages 492–498 (2001)Cite this article

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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Figure 1: Model for SRP-mediated targeting of ribosome-nascent chain complexes.
Figure 2: Crystal structures of SRP pathway components.
Figure 3: Model for SecB-mediated protein targeting.
Figure 4: Crystal structure of the H. Influenza SecB protein (1FX3)28.
Figure 5: Low resolution projection maps of the SecYEG structures48.

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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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  1. Erik H. Manting

    Present address: Department of Clinical Viro-immunology, Sanquin-CLB, Plesmanlaan 125, 1066 CX, Amsterdam, The Netherlands

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  1. Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Kerklaan 30, Haren, 9751 NN, The Netherlands

    Arnold J.M. Driessen, Erik H. Manting & Chris van der Does

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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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