Localization of the Tat translocon components in Escherichia coli

authored by

Felix Berthelmann, Thomas Brüser

Abstract

The Tat system has the ability to translocate folded proteins across the bacterial cytoplasmic membrane. In Escherichia coli, three functionally different translocon components have been identified, namely TatA, TatB, and TatC. These proteins were fused to the green fluorescent protein (GFP) and their localization was determined by confocal laser scanning fluorescence microscopy. TatA-GFP was distributed in the membrane, often with higher abundance at the poles. TatB-GFP was found in distinct spots at the poles of the cells. The fluorescence of TatC-GFP was very low and required a constitutive expression system to become higher than background, but then appearing polar. All three constructs complemented the chain-formation phenotype of corresponding mutant strains, indicating the functionality of the fusion proteins. TatB-GFP and TatC-GFP also complemented TMAO respiration deficiency and TatA-GFP the SDS-sensitivity of the mutant strains. The localization of the translocon-GFP fusions coincides with the fluorescence pattern of GFP fusions to Tat substrate signal sequences. We suggest that the active translocon complexes are mainly present at polar positions in Escherichia coli.

Organisation(s)

Institute of Microbiology

External Organisation(s)

Martin Luther University Halle-Wittenberg

Type

Article

Journal

FEBS Letters

Volume

569

Pages

82-88

No. of pages

7

ISSN

0014-5793

Publication date

02.07.2004

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Biophysics, Structural Biology, Biochemistry, Molecular Biology, Genetics, Cell Biology

Electronic version(s)

https://doi.org/10.1016/j.febslet.2004.05.054 (Access: Unknown)