The Escherichia coli twin‐arginine translocase: conserved residues of TatA and TatB family components involved in protein transport

FEBS Letters

Porcelli, Ida²  Hicks, Matthew G¹  Buchanan, Grant¹  Berks, Ben C²  Palmer, Tracy¹  de Leeuw, Erik² 

[1] Department of Molecular Microbiology, John Innes Centre, Norwich NR4 7UH, UK;Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK

关键词: Protein transport;    Tat pathway;    Twin-arginine signal peptide;    Trimethylamine N-oxide reductase;    Site-directed mutagenesis;   

DOI  :  10.1016/S0014-5793(03)00198-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The Escherichia coli Tat system serves to export folded proteins harbouring an N-terminal twin-arginine signal peptide across the cytoplasmic membrane. In this report we have studied the functions of conserved residues within the structurally related TatA and TatB proteins. Our results demonstrate that there are two regions within each protein of high sequence conservation that are critical for efficient Tat translocase function. The first region is the interdomain hinge between the transmembrane and the amphipathic α-helices of TatA and TatB proteins. The second region is within the amphipathic helices of TatA and TatB. In particular an invariant phenylalanine residue within TatA proteins is essential for activity, whereas a string of glutamic acid residues on the same face of the amphipathic helix of TatB is important for function.

【 授权许可】

Unknown