Towards understanding the Tat translocation mechanism through structural and biophysical studies of the amphipathic region of TatA from Escherichia coli.

ABSTRACT: The twin-arginine translocase (Tat) system is used by many bacteria and plants to move folded proteins across the cytoplasmic or thylakoid membrane. In most bacteria, the TatA protein is believed to form a defined pore in the membrane through homo-oligomerization with other TatA protomers. The predicted secondary structure of TatA includes a transmembrane helix, an amphipathic helix, and an unstructured C-terminal region. Here biophysical and structural investigations were performed on a synthetic peptide representing the amphipathic region of TatA (residues 22 to 44, abbreviated TatAH2). The C-terminal region of TatA (residues 44-89) was previously shown to be accessible from both the cytoplasmic and periplasmic sides of the membrane only when the membrane potential was intact, suggesting

SUBMITTER: Chan CS 

PROVIDER: S-EPMC3290633 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature