Structural features of the TatC membrane protein that determine docking and insertion of a twin-arginine signal peptide

Abstract: Twin-arginine translocation (Tat) systems transport folded proteins across cellular membranes with the concerted action of mostly three membrane proteins: TatA, TatB, and TatC. Hetero-oligomers of TatB and TatC form circular substrate–receptor complexes with a central binding cavity for twin-arginine–containing signal peptides. After binding of the substrate, energy from an electro-chemical proton gradient is transduced into the recruitment of TatA oligomers and into the actual translocation event. We previously reported that Tat-dependent protein translocation into membrane vesicles of Escherichia coli is blocked by the compound N,N′-dicyclohexylcarbodiimide (DCCD, DCC). We have now identified a highly conserved glutamate residue in the transmembrane region of E. coli TatC, which when modified by DCCD interferes with the deep insertion of a Tat signal peptide into the TatBC receptor complex. Our findings are consistent with a hydrophobic binding cavity formed by TatB and TatC inside the lipid bilayer. Moreover, we found that DCCD mediates discrete intramolecular cross-links of E. coli TatC involving both its N- and C-tails. These results confirm the close proximity of two distant sequence sections of TatC proposed to concertedly function as the primary docking site for twin-arginine signal peptides

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch
• Notes: Journal of biological chemistry. - 292, 52 (2017) , 21320-21329, ISSN: 1083-351X

Contributors, Places and Time

• Event: Veröffentlichung
• (where): Freiburg
• (who): Universität
• (when): 2019
• Creator: Blümmel, Anne-Sophie ; Drepper, Friedel ; Knapp, Bettina ; Eimer, Ekaterina ; Warscheid, Bettina ; Müller, Matthias ; Fröbel, Julia
• Contributor: Albert-Ludwigs-Universität Freiburg. Biochemie - Funktionelle Proteomforschung und Synthetische Biologie

Further information

• DOI: 10.1074/jbc.m117.812560
• URN: urn:nbn:de:bsz:25-freidok-1411128
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 25.03.2025, 1:49 PM CET