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Updated: Jun 13, 2026

Förster Resonance Energy Transfer Mapping: A New Methodology to Elucidate Global Structural Features
Published on: March 16, 2022
Purification and functional reconstitution of the bacterial protein translocation pore, the SecYEG complex
Ilja Kusters1, Geert van den Bogaart, Janny de Wit
1Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands.
Abstract:
In bacteria, proteins are secreted across the cytoplasmic membrane by a protein complex termed translocase. The ability to study the activity of the translocase in vitro using purified proteins has been instrumental for our understanding of the mechanisms underlying this process. Here, we describe the protocols for the purification and reconstitution of the SecYEG complex in an active state into liposomes. In addition, fluorescence based in vitro assays are described that allow monitoring translocation activity discontinuously and in real time.
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