Whitley, P.; Zander, Thomas; Ehrmann, Michael; Haardt, M.; Bremer, E.; von Heijne, G:
Sec-independent translocation of a 100-residue periplasmic N-terminal tail in the E.coli inner membrane protein proW
In: The EMBO Journal, Vol. 13 (1994), No. 19, pp. 4653 - 4661
1994article/chapter in journal
BiologyFaculty of Biology
Related: 1 publication(s)
Title:
Sec-independent translocation of a 100-residue periplasmic N-terminal tail in the E.coli inner membrane protein proW
Author:
Whitley, P.;Zander, Thomas;Ehrmann, MichaelUDE
LSF ID
13331
ORCID
0000-0002-1927-260XORCID iD
Other
connected with university
;
Haardt, M.;Bremer, E.;von Heijne, G
Year of publication:
1994

Abstract:

The ProW protein, located in the inner membrane of Escherichia coli, has a very unusual topology with a 100-residue-long N-terminal tail protruding into the periplasmic space. We have studied the mechanism of membrane translocation of the periplasmic tail by analysing ProW-PhoA and ProW-Lep fusion proteins, both in wild-type cells and in cells with an impaired sec machinery. Our results show that the translocation efficiency is not affected by treatments that compromise the SecA and SecY functions, but that translocation is completely blocked by dissipation of the proton motive force or by the introduction of extra positively charged residues into the N-terminal tail. This suggests that the sec machinery can act properly only on domains located on the C-terminal side of a translocation signal, and that the N-terminal tail is driven through the membrane by a mechanism that involves the proton motive force.