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Updated: Jun 13, 2026

Monitoring the Assembly of a Secreted Bacterial Virulence Factor Using Site-specific Crosslinking
Published on: December 17, 2013
Site-specific cross-linking of in vitro synthesized E. coli preproteins for investigating transmembrane translocation
Sascha Panahandeh1, Matthias Müller
1Institute of Biochemistry and Molecular Biology, ZBMZ, University of Freiburg, Freiburg, Germany.
Abstract:
A method is described for the preparation and usage of an E. coli cell-free translation system primed to incorporate the commercially available photoreactive analogue of phenyalanine, pBpa, into newly synthesized proteins. Incorporation is achieved by means of an amber suppressor tRNA specifically charged with pBpa. The method is exemplified for the site-specific photocross-linking of the signal sequence of a Tat (twin-arginine translocation) precursor protein to the Tat translocase in the cytoplasmic membrane of E. coli.
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