PMID:17545291

Citation	Punginelli, C, Maldonado, B, Grahl, S, Jack, R, Alami, M, Schröder, J, Berks, BC and Palmer, T (2007) Cysteine scanning mutagenesis and topological mapping of the Escherichia coli twin-arginine translocase TatC Component. J. Bacteriol. 189:5482-94
Abstract	The TatC protein is an essential component of the Escherichia coli twin-arginine (Tat) protein translocation pathway. It is a polytopic membrane protein that forms a complex with TatB, together acting as the receptor for Tat substrates. In this study we have constructed 57 individual cysteine substitutions throughout the protein. Each of the substitutions resulted in a TatC protein that was competent to support Tat-dependent protein translocation. Accessibility studies with membrane-permeant and -impermeant thiol-reactive reagents demonstrated that TatC has six transmembrane helices, rather than the four suggested by a previous study (K. Gouffi, C.-L. Santini, and L.-F. Wu, FEBS Lett. 525:65-70, 2002). Disulfide cross-linking experiments with TatC proteins containing single cysteine residues showed that each transmembrane domain of TatC was able to interact with the same domain from a neighboring TatC protein. Surprisingly, only three of these cysteine variants retained the ability to cross-link at low temperatures. These results are consistent with the likelihood that most of the disulfide cross-links are between TatC proteins in separate TatBC complexes, suggesting that TatC is located on the periphery of the complex.
Links	PubMed PMC1951830 Online version:10.1128/JB.00647-07
Keywords	Amino Acid Substitution; Escherichia coli/chemistry; Escherichia coli/genetics; Escherichia coli/metabolism; Escherichia coli Proteins/chemistry; Escherichia coli Proteins/genetics; Escherichia coli Proteins/metabolism; Membrane Transport Proteins/chemistry; Membrane Transport Proteins/genetics; Membrane Transport Proteins/metabolism; Models, Biological; Models, Molecular; Mutagenesis, Site-Directed; Protein Binding; Protein Interaction Mapping; Protein Structure, Secondary; Temperature
edit table

Significance

You can help EcoliWiki by summarizing why this paper is useful

Useful Materials and Methods

You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.

Annotations

<annotationlinks/>

EcoliWiki Links

Add links to pages that link here (e.g. gene, product, method pages)

References

See Help:References for how to manage references in EcoliWiki.