TatA and TatB generate a hydrophobic mismatch important for the function and assembly of the Tat translocon in Escherichia coli.

ABSTRACT: The twin-arginine translocation (Tat) system serves to translocate folded proteins across energy-transducing membranes in bacteria, archaea, plastids, and some mitochondria. In Escherichia coli, TatA, TatB, and TatC constitute functional translocons. TatA and TatB both possess an N-terminal transmembrane helix (TMH) followed by an amphipathic helix. The TMHs of TatA and TatB generate a hydrophobic mismatch with the membrane, as the helices comprise only 12 consecutive hydrophobic residues; however, the purpose of this mismatch is unclear. Here, we shortened or extended this stretch of hydrophobic residues in either TatA, TatB, or both and analyzed effects on translocon function and assembly. We found the WT length helices functioned best, but some variation was clearly tolerated. Defects i

SUBMITTER: Mehner-Breitfeld D 

PROVIDER: S-EPMC9424591 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature