Cell envelope adaptation and minimal Tat translocation are functionally intertwined

ABSTRACT: Protein secretion is key for bacterial growth, survival and adaptation. In the Gram-positive bacterium Bacillus subtilis, the twin-arginine (Tat) pathway serves in the exclusive secretion of proteins with bound cofactors. The Bacillus Tat pathway stands out for its minimalist nature with two independently acting translocases being composed of dedicated TatA and TatC subunits only. Here we addressed the question whether one of these translocases, TatAyCy, recruits additional common cellular components for activity. To this end, TatAyCy was purified by affinity chromatography and gel filtration, and interacting co-purified proteins were identified by mass spectrometry. This revealed the cell envelope stress responsive LiaH protein as an appendix to the TatAyCy complex. Importantly, our functional studies show that Tat expression is tightly trailed by LiaH induction, and that LiaH itself determines the capacity and quality of Tat-dependent protein translocation. Altogether, our observations show that protein translocation by the minimal Tat translocase TatAyCy is tightly intertwined with an adequate bacterial response to cell envelope stress. This is consistent with a critical need to maintain cellular homeostasis, especially when the membrane is widely opened to permit passage of large fully-folded proteins via Tat.

INSTRUMENT(S): LTQ Orbitrap

ORGANISM(S): Bacillus Subtilis Subsp. Subtilis

SUBMITTER: Minia Antelo  

LAB HEAD: Jan Maarten van Dijl

PROVIDER: PXD012842 | Pride | 2022-08-11

REPOSITORIES: Pride