The Sec system.

A J Driessen; P Fekkes; J P van der Wolk

doi:10.1016/s1369-5274(98)80014-3

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PubMed · 10066476

The Sec system.

A J Driessen·P Fekkes·J P van der Wolk

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Abstract

Proteins designated to be secreted by Escherichia coli are synthesized with an amino-terminal signal peptide and associate as nascent chains with the export-specific chaperone SecB. Translocation occurs at a multisubunit membrane-bound enzyme termed translocase, which consists of a peripheral preprotein-binding site and an ATPase domain termed SecA, a core heterotrimeric integral membrane protein complex with SecY, SecE and SecG as subunits, and an accessory integral membrane protein complex containing SecD and SecF. Major new insights have been gained into the cascade of preprotein targeting events and the enzymatic mechanism or preprotein translocation. It has become clear that preproteins are translocated in a stepwise fashion involving large nucleotide-induced conformational changes of the molecular motor SecA that propels the translocation reaction.

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Adenosine Triphosphatases Bacterial Proteins Biological Transport Cell Membrane Escherichia coli Escherichia coli Proteins Membrane Proteins Membrane Transport Proteins Molecular Chaperones Protein Sorting Signals SEC Translocation Channels SecA Proteins Journal Article Research Support, Non-U.S. Gov't Review

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A J Driessen, P Fekkes, J P van der Wolk. 1998. The Sec system.. https://doi.org/10.1016/s1369-5274(98)80014-3

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