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Updated: Sep 30, 2026

Förster Resonance Energy Transfer Mapping: A New Methodology to Elucidate Global Structural Features
Published on: March 16, 2022
The core of the bacterial translocase harbors a tilted transmembrane segment 3 of SecE
Andreas K J Veenendaal1, Chris Van Der Does, Arnold J M Driessen
1Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Kerklaan 30, 9751 NN Haren, The Netherlands.
Abstract:
The bacterial translocase mediates the translocation and membrane integration of proteins. The integral membrane proteins SecY and SecE are conserved core subunits of the translocase. Previous cysteine-scanning studies showed that the transmembrane segment (TMS) 3 of SecE contacts TMS 2 and 7 of SecY, and TMS 3 of another SecE. We now demonstrate that SecE also contacts TMS 10 of SecY. Combining all available cysteine-scanning mutagenesis data, a three-dimensional model has been built in which the positions of the helices that form the central core of the bacterial translocase are mapped. Remarkably, this model reveals that TMS 3 of SecE is strongly tilted relative to SecY.
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